Preliminary 2005 SOHO LASCO Coronal Mass Ejection List (Revised 31-Dec-2005 -- GAS) N.B. This is a working version of a catalogue of activity and probable coronal mass ejections detected in white light observations of the LASCO coronagraphs. This list is maintained at the SOHO Experimenters' Operations Facility, and it is based on an examination of only quick-look data, which represents a subset of the final LASCO dataset. Questions about this list should be directed to: planner@lasco6.nascom.nasa.gov . Note some changes to lists from earlier years: 1) Smaller events 'now' taken into account when possible due to the decline of the solar activity cycle. DATE UT Location Comment 01-Jan-2005: ************ 00:54 E - Wide ragged loop front just appearing above the E Limb. An (HALO) extremely faint and diffuse loop-like extension can be guessed above the S Pole by the time. By 01:31 UT, a big CME can be seen spanning almost all around the eastern limb with very faint extensions on the S Pole and western hemisphere. The event is first seen in C3 at 01:42 UT above the E Limb with very faint extensions already surrounding the occulting disk. The mean plane-of-sky speed of the LE of the CME (based on C3 data) at PA 87 was ~ 800 km/sec (showing practically no acceleration). Gusty outflow on ESE afterward as well as some faint and not- well-defined fronts, all along the day and well into next day. GOES reported a X1.7 X-ray flare from NOAA AR 10715 (N06E34) between 00:01 - 00:39 UT, with peak emission at 00:31 UT. EIT 195 images show a brightening on the aforementioned AR starting at 00:12 UT, clear signature of the X 1.7 X-ray flare. An intensity disturbance (wave) can be seen afterward with epicenter in the aforementioned AR; also a dimming region mainly to W and S of the AR. In summary, the event has therefore been determined as an asymmetric 'full' halo event, frontsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050101. 08:30 WNW - Faint raged front. Lot of infalling material, as well as gusty outflow all above the W Limb, all along the day. 21:30 W - Diffuse spray-like front (asymmetric loop-like feature brighter to S). Extremely faint loop-like extensions to N and further out. ---------------------------------------------------------------------------------- 02-Jan-2005: ************ E-ESE - Gusty outflow and some faint and not-well-defined fronts all along the day. 07:54 S - Diffuse curved feature developing toward SSW. It fades in C3 (very faint). 09:30 E - Very faint and diffuse loop front that fades close to the inner edge of C3. 10:34 W - Spray-like front. It fades throughout C3. preceded by an expanding (and very faint) ragged loop-like feature to N. 12:30 WNW - "Pair formation". Separation point at ~ 4.55 solar radii (at PA ~ 293). ---------------------------------------------------------------------------------- 03-Jan-2005: ************ W - Infalling material all along the day. Some small blobs coming out all above NW - W - SW limbs. 04:54 E - Very diffuse and faint brightening develops, extending up to the N Pole. By 05:30 UT, it is followed on ESE by an expanding ragged loop front. Structures on N are seen to be pushed toward NNW. By 06:54 UT another faint loop front follows, also on ESE. GOES reported a C3.8 X-ray flare from NOAA AR 10715 (N05E07) between 04:02 - 04:48 UT with peak emission at 04:22 UT. C3 shows a very faint and wide CME developing toward ESE (first seen at 07:42 UT). 17:30 SSW - Ragged and elongated loop front, barely visible in C3. 19:31 WNW - Very faint curved structure that fades throughput C2. 23:30 W - Fan-like front preceding at 00:30 UT on next day a kind-of spray-like front. Infalling material to N. ---------------------------------------------------------------------------------- 04-Jan-2005: ************ 09:30 WNW - Brigh loop front with inner core exhibiting faint extensions to N and S. EIT 195 images show a prominence lift-off starting at around 08:36 UT, very close to the W Limb. Big and clear Limb CME signatures. Mean plane of-sky-speed based on C3 data at PA 293 was around 1000 km/sec (slightly decelerated). 10:54 W - Very faint and diffuse front above the W Limb. By By 12:54 UT (HALO) a diffuse front is seen apparently covering the C2 occulting disk. It is really difficult to distinguish its faint signatures in the C2 FOV due to a previous big limb CME on WNW Limb, (see event reported to start at 09:30 UT). Coming back to the faint Event, it was first seen in C3 at 11:42 UT in the western hemisphere, in the aftermath of previous limb event, though it is difficult to be certain due to its extreme faintness. A very rough and crude estimation of its mean plane-of-sky speed (based on C3 data) at PA 260 is ~ 460 km/sec (showing practically no acceleration). The error in the estimation is big as it is practically impossible to define the position of the LE. GOES reported several C-class X-ray flares during the day from NOAA AR 10715. In particular, a C7.3 X-ray flare (N05W11) between 10:53 - 11:29 UT with peak emission at 11:13 UT. EIT 195 images show, between 10:48 - 11:48 UT, a brightening on the AR metioned above followed by CME event characterized by a dimming in the triangle delimited by NOAA AR 10715, 10716, and trailing part of 10715. After 11:00 UT the dimming spreads to N and W of AR 10715. Also, an important intensity disturbance (wave) developing mainly toward W and S of the AR. In summary, the event has therefore been determined as an extremely faint 'full' halo event, slightly asymmetric, frontsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050104. 15:06 SW - Extremely faint and wide loop front spanning all above the S Pole. Barely visible in C3 on SW (it fades close to the inner edge). Another one seems to develop in C2 since a little bit earlier on SE. Also very difficult to discern in C3, if discernible at all. 22:06 SE - Pair formation. Separation point at ~ 3.9 solar radii (PA ~ 128). ---------------------------------------------------------------------------------- 05-Jan-2005: ************ 05:54 NW - Brightening along streamer (with extremely faint and diffuse Partial extensions to both sides), followed by a wide and diffuse front Halo above the W Limb at 06:30 UT. By 12:06 UT, the whole event spans in the C2 FOV from about PA 210 - 030. C3 images show a diffuse and faint front above the W Limb starting at 08:42 UT. The event clearly spans over the N Pole by 12:42 UT. A rough estimation (LE very diffuse an faint) of its mean plane-of-sky speed (based on C3 data) at PA 282 is ~ 300 km/sec (showing practically no acceleration). GOES reported a B8.4 X-ray flare on NOAA AR 10715 (N08W25) between 04:04 - 06:00 UT with peak emission at 05:27 UT, most probably associated with the event observed by LASCO. EIT 195 observes a filament channel activation on AR 10715 and a dimming region to W, SW, and S of the AR between around 04:00 - 05:48 UT (development of a CME coming out from nearby the AR). In summary, the event has therefore been determined as a very faint (at least) 'partial' halo event, most probably frontsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050105a. **** LASCO Data Gap between 14:00 - 15:30 UT **** **** due to ICAL 01 (Intercalibration EIT/CDS) **** 15:30 E - Diffuse expanding loop-like front followed by core material. By (HALO) around 16:54 UT the C2 occulting disk seems to be completely covered. The event is first seen in C3 at 16:18 UT above the E Limb. By 18:18 UT the C3 occulting disk is completely covered. The mean plane-of-sky speed of the LE at PA 86 was about 725 km/sec (slightly accelerated). EIT 195 images show a big filament on the NE quadrant that begins to erupt, at the beginning very slowly, by around 13:13 UT. The last EIT 195 image prior to the 195 data gap (due to ICAL01) was taken at 13:48 UT, the filament still on the disk. At 15:24 UT, first image after the data gap, the filament is already gone, nice and big post-event arcades starting to develop. GOES reported a relative increase in the X-ray flux at around 15:00 UT (almost B1). In summary, the event has therefore been determined as an asymmetric 'full' halo event, frontsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050105b. 23:06 ENE - Very faint asymmetric loop front. ---------------------------------------------------------------------------------- 06-Jan-2005: ************ 08:54 WNW - Jet-like front developing toward NW, followed by a similar one at 10:06 UT. 12:54 W - Very faint expanding ragged front that fades in C2. 15:30 W - Bright loop front. Ragged front to S. 15:54 ENE - Very faint and difuse front followed at 21:30 UT by a not-well- defined front. Slow development of a faint system of loops along a streamer superposed in the LOS. ---------------------------------------------------------------------------------- 07-Jan-2005: ************ 10:30 ENE - Bright loop front that fades throughout C3. EIT 195 observes a backsided CME starting at 09:48 UT. Some infalling material afterward in C2. 21:54 ENE - Ragged loop front that fades close to the inner edge of C3, followed at 23:54 UT by a faint and diffuse ragged front on E Limb. ---------------------------------------------------------------------------------- 08-Jan-2005: ************ 03:54 E - Jet-like front. Infalling material to N. Another narrow front at ~ 09:54 UT. 06:06 SE - Expanding loop front. Faint extensions can be seen ahead of the event in C3, spanning up to above the S Pole (starting at around 08:42 UT). The whole event fades throughout C3. No visible signatures on EIT 195 running difference images. 06:30 NW - Expanding loop front fainter than previous event on SE (and apparently slower). It apparently fades throughout C2. No visible signatures of the event on EIT 195 running difference images. 13:54 N - Extremely faint and not-well-defined front developing toward NNW, followed at 16:30 UT by faint ragged front. An expanding front that later extends all above the N Pole, from NW to NE, appears by around 20:30 - 20:58 UT. Also by 20:58 UT, a faint and expanding loop front is seen appearing on NE, though it is difficult to disentangle the different structures involved. EIT 195 shows no signatures of the event, except for the release of material on NE starting at around 18:12 UT. 17:54 W - Faint and very diffuse elongated front preceding a ragged and elongated expanding loop-like front (first seen at around 18:54 UT) that fades close to the inner edge of C3. 20:58 E - Faint and elongated ragged loop front. ---------------------------------------------------------------------------------- 09-Jan-2005: ************ 02:30 NE - Bright loop front and twisted trailing structure. EIT 195 images show a backsided CME starting at around 01:48 UT on ENE Limb. Mean plane-of-sky speed based on C3 data: ~ 600 km/sec at PA ~52. Angular span at 09:18 UT (C3): ~ 70 deg, from PA ~ 19 - 89. 03:54 NNW - Faint loop front that fades throughout C3. 06:06 SW - Jet-like front. 07:31 WSW - Elongated and ragged loop front a little to N of previous event (jet) superposed in the LOS with a narrow and elongated fan-like front. They fade throughout C3. 09:06 E - Bright and wide loop front. Mean plane-of-sky speed based on C3 data: ~ 820 km/sec at PA ~ 115. Angular span at 12:42 UT (C3): ~ 130 deg, from PA 40 - 170. Many ragged fronts all above the eastern limb (from NE to SE) along the rest of the day. Also some infalling material. GOES recorded an M2.4 X-ray flare from NOAA AR 10719 (S09E70) between 08:25 - 09:09 UT with peak emission at 08:51 UT. Also a C2.6 X-ray flare between 14:33 - 14:56 UT with peak emission at 14:47 UT on the same AR (S09E68); both during a long duration X-ray event. Signs of a wave to S and SSW of the AR on EIT 195 images. ---------------------------------------------------------------------------------- 10-Jan-2005: ************ 00:30 ESE - Ragged front immediately followed (to N) by a fainter front developing faster. Infalling material on E. Another ragged front on ENE by ~ 02:30 UT. 08:54 E - Blob-like front developing slightly toward ENE. It fades in C3. 11:06 NE - Ragged front that fades throughout C3. Still more infalling material above the E Limb. **** LASCO Data Gap between 18:30 - 21:54 UT. **** 21:54 SE - Slow development of a wide and diffuse loop-like front already under development after data gap. Bright structure inside. Mean plane-of-sky speed of the outermost front (LE) based on C3 data at PA 123: ~ 304 km/sec, slightly accelerated. As for the inner structure, its mean plane-of-sky speed at PA 123 was about 272 km/sec, also slightly accelerated (though lower value than that of the outermost front). Angular span of the event at 09:18 UT (C3): ~ 100 deg, from PA 080 - 180. ---------------------------------------------------------------------------------- 11-Jan-2005: ************ 01:31 SW - Extremely faint small fronts start to be discernible in C2, already far from the inner edge. EIT 195 images show the eruption of a prominence between 22:24 - 23:36 UT on SW, showing then continued outflow in emission until about 08:00 UT. 03:54 NE - Faint and diffuse expanding loop front that fades throughout C3. 06:06 W - Faint loop front just appearing preceded by a another faint and not-well-defined front at ~ 03:54 UT. 06:06 SE - Very faint and diffuse front superposed in the LOS with the aftermath of event reported to start at 21:54 UT on previous day. By 07:54 UT, a faint expanding loop front starts to be seen above the E Limb. It fades throughout C3. Much outflow to S, extending into next day. 09:30 NNW - Couple of very faint front starts to be discernible. They fade throughout C3. By 12:54 UT, infalling 'v-shaped' structure discernible (the event looks like a 'pair formation' event). 17:30 NNE - Faint expanding loop front that fades throughout C3. Another one, fainter, on NNW apparently developing faster. 18:06 E - Faint and ragged expanding front. It also fades throughout C3. 23:30 SE - Faint and ragged expanding loop front, brighter to S. It fades throughout C3. ---------------------------------------------------------------------------------- 12-Jan-2005: ************ E - Gusty outflow in the form of small blobs all across the eastern limb, all along the day. 01:31 N - Extremely faint, barely visible, ragged front that fades throughout C3. ---------------------------------------------------------------------------------- 13-Jan-2005: ************ 01:54 ENE - Initially bright ragged loop front that fades throughout C2. A very faint and diffuse loop front, wider than the front previously mentioned, develops superposed in the LOS moving apparently faster. Gusty outflow all across the eastern limb continues. 05:30 W - Ragged and faint front followed by several small fronts developing slightly toward WSW. Some guty outflow on WSW. 08:54 E - Initially bright ragged and wide front that fades throughout C3. 15:06 ENE - Faint ragged loop front. It fades throughout C2. 17:30 ENE - Another faint ragged loop front, followed at 18:06 UT, by another similar front with very faint loop-like extensions on E-SE Limb. By 19:54 UT, another faint loop front develops on ENE followed by another (narrower) front at 20:56 UT. Very faint extensions can be seen all the way from E, and S Pole up to the SW Limb. Difficult to discern clearly with which front are they associated. GOES reported from NOAA AR 10718 the following X-ray flares by the time: . a C3.3 (S06E15) bewtween 16:24 - 16:37 UT, peak at 16:33 UT, . a C4.2 (S06E15) bewtween 17:04 - 17:17 UT, peak at 17:12 UT, . a C2.5 (S06E14) bewtween 18:53 - 19:09 UT, peak at 19:07 UT, and . a C1.2 (S06E13) bewtween 20:21 - 20:31 UT, peak at 20:26 UT. The whole complex event looks faint in C3 with the brightest part developing mainly toward NE, and only gusty outflow on SE. 23:54 ENE - Another faint ragged loop front. By 00:06 UT on next day, faint loop-like extensions can be seen again all the way from E, and S Pole up to the SW Limb. GOES reported a C6.8 X-ray flare from NOAA AR 10718 (S06E11) between 22:36 - 22:58 UT with peak emission at 22:52 UT. As with the previous event, it looks faint in C3 with the brightest part developing mainly toward NE, and only gusty outflow on SE. ---------------------------------------------------------------------------------- 14-Jan-2005: ************ 05:30 WSW - Faint front along streamer followed at 06:06 UT by another ragged front that fades throughout C3. 06:54 SSW - Kind of diffuse and elongated front that quickly fades. 11:30 WSW - Ragged front along streamer that fades throughout C3. 17:06 WSW - Another Ragged front along streamer. Very faint (rather) circular extensions around the C2 occulting disk by around 18:30 UT. No visible signatures in C3. GOES reported an M1.0 X-ray flare on NOAA AR 10718 (S06E02) between 16:02 - 16:14 UT with peak emission at 16:06 UT. EIT 195 images show, by 16:12 UT, a brightening on both sides of the neutral line of the AR, followed by a small dimming region to N of the AR. 23:54 S - Kind of diffuse and elongated (very faint) front developing toward SSW. It quickly fades. ---------------------------------------------------------------------------------- 15-Jan-2005: ************ NOTE: LASCO did not show evidence of any halo-like event associated with the X1.2 X-ray flare on NOAA AR 10720 (N14E08) that was recorded by GOES between 00:22 - 01:02 UT with peak emission at 00:43 UT on 2005/01/15. 06:30 N - Very bright loop front above the N Pole. A faint and diffuse (HALO) envelope (shock?) can be seen all around the loop front. By 06:54 UT, the C2 occulting disk is completely covered, the LE of the event on N being already out of the C2 FOV. The event is first seen in C3 at 06:42 UT above the N Pole, the C3 occulting disk being completely covered by 07:42 UT. It develops pretty fast: the LE on N crossed the end of the C3 FOV by around 09:42 UT. The mean plane-of-sky speed of the LE (outermost front of the diffuse envelope ahead of the loop-like feature) at PA 002 was ~2150 km/sec (as measured on C3 in only 3 frames, then out of the FOV). For the sake of completeness, the mean plane-of sky speed of the LE of the loop-like feature at PA ~ 0 was ~ 1850 km/sec (based on C3 data, only 3 frames). GOES reported multiple M-class flares and a couple of X-ray flares on NOAA AR 10720 during the day. In particular, an M8.6 X-ray flare occurred at N16E04 between 05:54 - 07:17 UT with peak emission at 06:38 UT, is the one most likely associated to the signatures observed on C2/C3, which happened just after a compact M8.4 X-ray flare on the same AR (N14E06) between 04:26 - 04:36 UT with peak emission at 04:31 UT. EIT 195 images show signatures of the event along and N of the (east-west) neutral line of AR 10720 between 06:00 - 07:13 UT. An intensity disturbance (wave) is seen mainly to N and NW of the AR, including the activation of a large filament channel (FC). In summary, the event has therefore been determined as an asymmetric 'full' halo event, frontsided. Expanding loop-like structures follow on NNW, most likely related to continued X-ray activity on AR 10720. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050115a. 14:54 WSW - Bright ragged loop front with apparently twisted trailing structure. Extremely faint extensions above the SE Limb and S Pole. GOES reported an M3.2 X-ray flare on NOAA AR 10718 (S08W12) between 14:08 - 14:39 UT with peak emission at 14:23 UT. EIT 195 images show a wave on disk toward S, SW, and NW of the AR after a brightening at 14:36 UT. 23:06 N-NW - Very bright loop front covering practically the whole NW (HALO) quadrant. The next C2 frame (23:30 UT) shows the C2 occulting disk completely covered. Early on next day a proton storm can be seen developing in the C2 FOV (also C3). The event is first seen in C3 at 23:18 UT above the NW Limb extending from the W up to past the N Pole. It is shown as a bright loop front surrounded by a fainter and diffuse envelope (shock?). By 23:42 UT, the C3 occulting disk is completely covered. By 01:42 UT (on next day), the LE on NW already crossed the outer edge of the C3 FOV. The mean plane-of-sky speed of the LE (outermost front of the diffuse envelope ahead of the loop-like feature) at PA 329 was ~2890 km/sec (as measured on C3 in only 2 frames, as it is too difficult to discern the feature tracked in the following frame, if not already out of the FOV). For the sake of completeness, the mean plane-of-sky speed of the LE of the loop- like feature at PA 329 was ~2400 km/sec (based on C3 data, only 3 frames). GOES reported an X2.6 X-ray flare during a long duration X-ray event on NOAA AR 10720 (N15W05) between 22:25 - 23:31 UT with peak emission at 23:02 UT, most likely associated to the signatures observed on C2/C3. EIT 195 images show a strong brightening on the aforementioned AR starting at ~ 22:36 UT, peaking by 23:12 UT (there is a small EIT data gap between 22:36 UT - 23:12 UT due to the C3 Polarization sequence taken during that time). FC to NW of the AR is blown away during the gap. In summary, the event has therefore been determined as an asymmetric 'full' halo event, frontsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050115b. ---------------------------------------------------------------------------------- 16-Jan-2005: ************ NOTE: Data degraded since early in the day by snowstorm (proton event). Degradation becomes more important after midday (UT time). 00:06 E - Faint system of wide loop fronts developing slightly toward ESE in the aftermath of previous halo. 05:30 NE - Brightening along streamer preceding an elongated and expanding loop-like structure. Some infallling material to S. 16:54 NW - Expanding 'curved' feature develops being 'pushed' toward N. It fades throughout C3. 20:30 SW - Elongated (and curved) loop-like front. NOTE: GOES recorded two M2-class flares (peak emissions on 2005/01/16 @ 22:03 UT and on 2005/01/17 @ 03:21 UT, respectively). No clear signatures of associated CME can be seen in LASCO data. ---------------------------------------------------------------------------------- 17-Jan-2005: ************ 09:30 NW - Very bright loop front on the NW quadrant surrounded by a very (HALO) tenuous and diffuse excess intensity, which in fact, can be guessed (though barely) in previous frame at 09:06 UT. By 09:54 UT, the LE on NW already exited the C2 FOV, the occulting disk being completely covered. Please note that at that time, a new bright and ragged front appears above the NW Limb. The snowstorm associated with the proton event reported to start on previous day is still present on the C2/C3 images, becoming progressively more important (by around 12:30 UT) until making the C2 images completely degraded by 14:07 UT (14:19 UT for C3). The event is first seen in C3 at 09:42 UT above the NW Limb. It is shown as a bright loop front surrounded by a fainter and diffuse envelope (shock?). The next frame at 10:20 UT shows i) the diffuse envelope, ii) the loop front, and iii) a much brighter ragged front, most likely the C3 counterpart of the front appearing in C2 at 09:54 UT. The C3 occulting disk is completely covered by that time, i.e., at 10:20 UT. The outermost LE of the 'complex' event reaches the end of the C3 FOV by 11:42 UT. The mean plane- of-sky speed of the LE of the outermost front of the diffuse envelope [i.e., feature described as i)] at PA 326 was about ~ 2185 km/sec (as measured on C3 in only 4 frames). On the other hand, the mean plane-of-sky speed of the apparently fastest outermost feature belonging to the bright loop [i.e., feature described as iii)] at PA 263 was 2350 km/sec (based on C3 data, only 4 frames). Given the superposition of structures during the development of the complex event, it is difficult to give a reliable value for the speed of the feature described as ii). GOES reported a long X-ray duration event on NOAA AR 10720: an X3.8 X-ray flare (N15W25) between 06:59 - 10:07 UT with peak emission at 09:52 UT, associated to the signatures observed on C2/C3; just after a compact C3.9 X-ray flare (N15W21) between 06:06 - 06:15 UT with peak emission at 06:10 UT. EIT 195 images show a steady increase in intensity on the AR 10720 since around 07:48 UT, peaking at 09:48 UT. Inspection of running differences show an 'intensity peak' at 08:00 UT followed by expanding loop- like structures toward NW. By 09:36 UT, the loops on NW of the AR open and then disappear followed by a wave to NNE, N, and NW of the AR. Another CME signature can be seen after 09:48 UT (time of the strongest brightening): wave to NNE, NW, W, SW, and SSW on disk plus NW, W, SW, SSW off-limb. In summary, the event has therefore been determined as an asymmetric and complex 'full' halo event, frontsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050117. NOTE: LASCO Data strongly degraded after proton event associated with the X-ray Flare/CME reported above. ---------------------------------------------------------------------------------- 18-Jan-2005: ************ NOTE: LASCO Data still strongly degraded (snowstorm) by proton event on previous day associated to the X3.8 X-ray flare and Complex Full Halo event. It is practically impossible to discern anything in the LASCO running difference images until around 16:51 UT. Then, snowstorm gradually subsiding. 17:14 NW - Expanding loop front followed at 19:42 by a bigger expanding front. 17:37 NE - Expanding ragged loop front that fades close to the inner edge of C3. ---------------------------------------------------------------------------------- 19-Jan-2005: ************ NOTE: LASCO/EIT observed a couple of events on 2005/01/19 that, considered together, look like an asymmetric and complex full halo event. However, closer inspection show that apparently, at least two different events occurred: i) a very asymmetric full halo CME, and ii) a relatively slow asymmetric full halo event. 08:29 NW - Very bright loop front above the NW limb surrounded by a tenuous (HALO) and diffuse excess intensity [Event i)]. By 09:06 UT, the LE on NW already exited the C2 FOV, trailing material coming out toward WNW and followed by much gusty outflow. Streamers on NE and SW are pushed away by the event. By that time, an apparently 09:28 NE - new faint and ragged structure [Event ii)] develops towards NE. Faint extensions from E up to the S Pole surround the C2 occulting disk by 09:39 UT. The event i) is first seen in C3 at 09:16 UT above the NW Limb as a clear loop front surrounded by a faint envelope, while event ii) is first seen appearing above the NE Limb by 10:10 UT. By that time, the C3 occulting disk is completely covered. The mean plane-of-sky speed of the different features involved was (based on C3 data): . LE of the outermost front of the diffuse envelope surrounding the loop front i): ~ 1960 km/sec at PA 321. . LE of the outermost feature of the bright loop i): ~ 1855 km/sec at PA 311. . LE of Event ii) at PA 056: 614 km/sec. GOES reported the following two X-ray events on NOAA AR 10720, most likely associated with the CME signatures observed on C2/C3: . M6.7 X-ray flare (N16W53) between 06:58-07:55 UT, peak @ 07:31 UT, . X1.3 X-ray flare (N15W51) between 08:03-08:40 UT, peak @ 08:22 UT. EIT 195 images show a strong increase in intensity on AR 10720 since around 07:17 UT peaking at 07:29 UT, 08:12 UT, and then again at 10:27 UT (see event reported to start at 10:54 UT). After first peaking, the brightening is followed by ejection of material toward NW until around 09:00 UT. A big wave can be seen mainly to NE, N, NW and SW of the AR. Later, at 10:05 UT, more material can be seen ejected, this time mainly toward NE-NNE of the AR. This happen at the same time as an apparently backsided CME on the E Limb. It is difficult to associate temporally any of the signatures seen in EIT with the event ii) observed in C2/C3. Even though, considering the events on NOAA AR 10720, the X-ray flares, and the signatures in C2/C3, the event can be determined as a very asymmetric and complex 'full' halo event, frontsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050119. 10:54 NW - Bright front starts developing toward NW inmerse in the evolution the halo event. GOES reported an M2.7 X-ray flare on NOAA AR 10720 (N17W52) between 10:19 - 10:29 UT with peak emission at 10:24 UT. 11:16 ENE - Bright spray-like front. 14:02 ESE - Elongated and aparently twisted structure with a diffuse front. 20:06 WNW - Faint and not-well-defined front followed by another one, a little bit brighter, at 21:54 UT. They both fade throughout C3. Some infalling material on W. ---------------------------------------------------------------------------------- 20-Jan-2005: ************ 00:06 NE - Ragged front along streamer. Barely visible in C3. 03:30 SW - Slow development of a system of loops along the streamer. 04:06 NW - Faint spray-like front. 06:54 NW - Extremely bright loop front above the WNW-NW limb. An intense (HALO) proton storm starts affecting by that time the LASCO images. The next C2 frame (07:34 UT) shows up 100 % contaminated and therefore practically useless. The same occurs with the Strongest following frames until the rest of the day. The proton event Proton is first seen in C3 at 07:54 UT, hiding any potential CME Storm signatures. The next frame allows to guess a ragged loop front since 1989 all above the SE Limb. By 10:24 UT the C3 occulting disk seems to be completely covered. If, the LE is what I guess it is, the mean plane-of-sky speed of that front at PA 141 would be around 571 km/sec (based on C3 data). However, given the projected development of this guessed halo (apparently mainly toward SE), it is difficult to be sure about its association with the C2 signature observed at 06:54 UT on NW. Maybe there is a front already farther out on NW, but the degradation of the data prevents telling anything. GOES(10) reported an X7.1 X-ray flare on NOAA AR 10720 (N14W61) between 06:36 - 07:26 UT with peak emission at 07:01 UT. EIT 195 images show between 06:36 - 06:48 UT a well-defined loop eruption toward NW above the AR 10720, clearly under way before the X7 flare. At 06:48 UT, a strong brightening starts to be seen on the aforementioned AR, peaking in the frame at 07:14 UT. Many particle hits by that time. Maximum particle counts occur by 07:27 UT. Given the data degradation due to the particle hits nothing can be said about potential dimming/wave associated to the event. It is difficult to be sure that the 'halo' guessed in C3 is really a halo or if it is really associated with the big event. However, due to the location of the source region of the event on the disk, is likely that the associated CME can at least be partly directed toward Earth. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050120. NOTE: LASCO Data strongly degraded after proton event (~ 07:00 UT), all along the rest of the day. Some small and/or faint events maybe missing. 09:31 NE - Elongated loop front. 17:06 NW - Very elongated loop front. Apparently, some faint ragged fronts follow. GOES reported a C8.0 X-ray flare from NOAA AR 10720 (N19W64) between 16:08 - 16:19 UT with peak emission at 16:14 UT. EIT observes a compact event between 16:22 - 16:35 UT on NE of the AR, possible wave to NNE, narrow CME off-limb. Couple of C-class flares follow (peak emission at 18:16 UT and 21:53 UT). ---------------------------------------------------------------------------------- 21-Jan-2005: ************ NOTE: LASCO Data still strongly degraded by proton event, though gradually subsiding. Some small and/or faint events maybe missing during the first half of the day. 04:58 WNW - Bright and elongated loop front. EIT 195 observes a compact brightening to NE of the AR 10720, eruption of a compact loop, and opening of larger, off-limb structures between 04:31 - 05:26 UT. GOES reported a C6.3 X-ray flare from NOAA AR 10720 (N19W69) between 04:17 - 04:34 UT with peak emission at 04:27 UT. Couple of C1-class X-ray flares more, peaking at 06:36 and 06:46 UT on AR 10720. 07:23 SE - Elongated and very narrow diffuse loop-like structure that fades close to the inner edge of C3. 10:58 WNW - Another bright and elongated loop front (narrower than the previous one). Gusty outflow. GOES reported an M1.7 X-ray flare from NOAA AR 10720 (N19W81) between 10:10 - 10:19 UT with peak emission at 10:16 UT. 15:18 W - Ragged front that quickly fades developing slightly toward WSW precedes another (bigger) ragged front at 17:30 UT, which fades throughout C3. 23:30 WNW - In the gusty outflow, a very faint and not-well-defined front can be discerned (difficult to give an exact time of first appearance). It fades throughout C3. ---------------------------------------------------------------------------------- 22-Jan-2005: ************ 01:31 E - Jet-like front that quickly fades. 03:54 NNE - Ragged front along streamer that fades in C3. 03:54 WSW - Not-well-defined front that quickly fades. 16:30 S - Extremely faint and diffuse wide loop front developing very slowly. It is very difficult to give an exact time of first appearance. By the end of the day is clearly discerned already half way to the end of the C2 FOV. 17:30 WNW - Initially bright loop front that apparently fades throughout C2. 20:30 NW - Diffuse jet-like front (just to N of previous event) that quickly fade. 23:06 WNW - Ragged loop front that fades throughout C3. Gusty outflow well into next day. ---------------------------------------------------------------------------------- 23-Jan-2005: ************ 00:06 ESE - Very thin and elongated loop-like structure (jet-like) at a position angle that roughly matches that of the south-eastern leg of event reported to start at 16:30 UT on previous day. 17:06 SSE - Extremely faint expanding loop front already half way to the end of the C2 FOV starts to be discernible. Some infalling material by the time. It fades throughout C3. ---------------------------------------------------------------------------------- 24-Jan-2005: ************ 00:30 W - Small blob-like front. Infalling material. 05:30 ESE - Very faint loop front that quickly fades. By that time, and a little bit to S, starts to be visible a faint and elongated loop front (and corresponding infalling material). 05:30 WNW - Faint and very elongated structure that fades very close to the inner edge of C3. 11:30 E - Elongated loop-like structure with a fan-like front. It fades throughout C3. 23:06 E - Faint and asymmetric expanding loop front that fades close to the inner edge of C3. ---------------------------------------------------------------------------------- 25-Jan-2005: ************ 00:54 SW - Expanding and asymmetric loop front that fades throughout C3. By 06:30 UT, a couple of faint loop-like fronts become discernible. Another one at ~ 12:30 UT. They all also fade throughout C3. 17:06 ESE - Faint and diffuse loop front that quickly fades. ---------------------------------------------------------------------------------- 26-Jan-2005: ************ 05:30 ENE - Very faint and diffuse loop front surrounding a system of expanding loops along streamer. Barely visible in C3. 07:54 WSW - Several faint and diffuse fronts that quickly fade (in particular, at 07:54, 09:06, 11:30, 20:06, and 22:30 UT). ---------------------------------------------------------------------------------- 27-Jan-2005: ************ 03:54 S - Extremely faint elongated blob-like feature that fades in C2. 06:30 W - Initially bright small loop front develops as a faint ragged front toward WSW. 07:31 SE - Development of several ragged and faint fronts along the streamer. Difficult to give an exact time of first appearance. 11:30 W - Another initially bright small loop front develops as a faint ragged front toward WSW. Infalling material on WNW. 14:54 W - Again another initially bright small loop front develops as a faint ragged front toward WSW. 16:30 W - Again another initially bright small loop front develops as a faint ragged front toward WSW. 22:06 W - Faint and diffuse front toward WSW that quickly fades. ---------------------------------------------------------------------------------- 28-Jan-2005: ************ 00:54 WSW - Following the series of similar events on previous day, another initially bright small loop front that develops as a faint and ragged front. 06:54 W - Faint and diffuse loop front followed at 07:54 UT by another one, elongated, that fades throughout C3. 09:30 NW - Faint and elongated loop-like structure that fades in C3. Infalling material. 11:54 WSW - Ragged loop front. By 12:30 UT, an initially bright (small) structure follows a little bit to S (along streamer). It fades throughout C3. Afterward (~ 15:30 UT), the slow development of a faint system of loops along the streamer starts to be discerned (on SW), continuing well into next day. 20:54 E - Jet-like front. ---------------------------------------------------------------------------------- 29-Jan-2005: ************ 03:54 N - Faint blob like front starts to be discerned already half way to the end of C2 FOV, developing slightly toward NNW. 04:30 NW - Diffuse and ragged loop front. Faint extensions on W and SW, making momentarily brighter the system of loops on the streamer on SW. 10:34 W - Elongated and narrow loop-like structure with a diffuse front. 13:54 W - Another elongated and narrow loop-like structure with a diffuse front. 17:30 W - Expanding spray-like front. ---------------------------------------------------------------------------------- 30-Jan-2005: ************ 15:54 SW - Wide expanding loop front, though a slight excess intensity can Partial be guessed already at 15:30 UT. Relative narrow ragged fronts Halo follow on SW, then gusty outflow. By 16:54 UT, a diffuse and expanding front can be seen on the E Limb. It is difficult to establish its association to the loop developing toward SW. By 18:54 UT the legs of the loop seem to be at PA ~095 and PA ~270, giving to the event an apparent angular span of ~ 175 deg (C2). However, extremely diffuse and faint extensions can be guessed above the NE Limb, and barely on the N Pole. The event was first seen in C3 at 17:18 UT on SW, preceded by diffuse and faint extensions above the W Limb. No signatures of the event can be discerned above the N Pole (if any, too faint). The mean plane- of-sky speed (based on C3 data) of the LE at PA 220 was around 445 km/sec. The HT profile shows a slight acceleration. No significant X-ray activity was reported by GOES by the time. Likewise, EIT 195 shows a quiet Sun, with no activity that could be related to the event observed by LASCO. In summary, and taking into account the lack of signatures above the N Pole on C3, and the lack of frontsided activity in EIT (as well as X-ray activity), the event has therefore been determined as a Partial Halo event, most probably backsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050130. ---------------------------------------------------------------------------------- 31-Jan-2005: ************ SW - Gusty outflow in the form of small ragged fronts, all along the day and well into next day. 03:54 NE - Very faint fan-like front that fades throughout C2. 07:31 SE - Big and bright loop front. By 07:54 UT, the northern leg of the loop reaches the ENE Limb. Trailing material, gusty outflow afterward in the form of brigh and small fronts along a current sheet. First seen in C3 at 07:42 UT. Faint and diffuse extensions discernible in C3 over the S Pole. Starting at 06:36 - 06:48 UT, EIT 195 running difference images show a big CME on SE, apparently originated on the back side. 10:30 SW - In the gusty outflow, an elongated and ragged loop front is discernible. It fades throughout C3. 18:30 E - Very faint and diffuse expanding ragged front that fades close to the inner edge of C3. 23:54 W - Spray-like front developing slightly toward WNW. It fades throughout C3. ================================================================================== 01-Feb-2005: ************ 06:06 NW - Very faint blob-like front starts to be visible at ~ 4.69 solar radii (PA ~ 315). An infalling structure can be seen by the time, a little bit to N. 11:06 NE - Very big and bright loop front. Close inspection shows that at (HALO) least two different features are present: i) a ragged loop front developing toward NE (hereafter Feature #1), and ii) a wider loop front, a little behind, initially spanning from the N Pole up to the E Limb with its brightest part above E (hereafter Feature #2). By 11:30 UT, faint and diffuse extensions surround completely the C2 occulting disk. Feature #1 is first seen in C3 at 11:18 UT above the NE Limb, surrounded by a faint and diffuse envelope that, in the next frame at 11:42 UT, seems to extend all the way from the E Limb, N Pole, up to the NW Limb; it gradually subsides in the next frames. Feature #2 appears above the E Limb at 11:42 UT. By 12:42 UT, the C3 occulting disk appears completely surrounded by a rather circular front, which seems to be related to Feature #2 rather than to Feature #1. The mean plane-of-sky speed (based on C3 data) of different parts of the complex event is given below: . LE of the faint and diffuse envelope surrounding Feature #1 at PA 040 : 1300 km/sec (slightly decelerated), . LE of Feature #1 at PA 046 : 1046 km/sec (slightly decelerated), . LE of Feature #2 at PA 112 : 700 km/sec (too ragged a LE to have a precise measurement), and . LE of the circular front that surrounds the C3 occulting disk by 12:42 UT at PA 298 : 495 km/sec (too ragged a LE to have a precise measurement). No significant X-ray activity was reported by GOES by the time. EIT 195 running difference images show no significant activity on the disk. However, signatures of a backsided CME above the NE Limb starting at 10:36 UT can be clearly seen. In summary, the event has therefore been determined as a complex Full Halo event, most probably backsided. Keep in mind that the global appearance of the event is given by the contribution of at least two different components (apparently both backsided). See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050201. 12:06 SW - During the development of one of the components of the halo event, a small system of loops develops along the streamer. The whole structure is being shifted toward the S Pole all along the day. 17:54 E - In the halo aftermath of the halo event, an elongated and ragged loop front that fades very close to the inner edge of C3. System of faint loops moving outward superposed in the LOS, until early on next day. 18:30 NE - Expanding loop front. By ~ 20:58 UT, a ragged loop front develops moving faster, and thus disturbing the development of the previous loop front. Gusty outflow follows well into next day. Some infalling material on E Limb. ---------------------------------------------------------------------------------- 02-Feb-2005: ************ E - Infalling material and release of some small blobs (apparently 'pair formation') above the E Limb all along the day. The most significant (clear) ones given below. 03:54 S - Continuous development of a system of diffuse and expanding loop fronts. 04:54 E - Pair formation. Separation point at ~ 3.45 solar radii (PA ~ 110). The outward-moving feature develops slightly toward ESE. 05:30 W - Spray-like front followed at 06:54 UT by a bright loop front developing slightly toward WNW. Only this loop front is discernible in C3. 10:30 NNE - Diffuse and elongated loop front that fades throughout C2. Another one at 12:06 UT developing toward the N Pole. 15:08 E - Pair formation. Separation point at ~ 3.15 solar radii (PA ~ 80). The outward-moving feature develops slightly toward ENE. 18:30 SSE - Another continuous development of a system of diffuse and expanding loop fronts. ---------------------------------------------------------------------------------- 03-Feb-2005: ************ ENE - Gusty outflow continues, all along the day. E...S - Release of small blobs all along the day. Some infolling material. 00:06 NNE - Couple of faint elongated loop fronts that quickly fade (one beside the other) 01:31 W - Faint and diffuse loop front developing toward WSW. 03:54 NE - Faint jet-like front. 05:30 W - Extremely faint and diffuse front that fades throughout C2. 08:54 WNW - Faint and diffuse system of expanding loop fronts. 15:54 W - Very faint and elongated loop-like structure that fades throughout C2. 23:54 W - Spray-like front. It fades throughout C3. ---------------------------------------------------------------------------------- 04-Feb-2005: ************ 03:08 ESE - Diffuse front that quickly fades. Afterward, slow development of a system of loops. By 06:30 UT, another diffuse front can be seen developing superposed in the LOS (not discernible in C3). Connection to event reported to start at 07:31 UT on NE ??? 07:31 NE - Diffuse and ragged loop front expanding toward N. It fades throughout C3. Some outflow afterward. 21:30 NW - Faint, diffuse, and not-well-defined front that quickly fades. ---------------------------------------------------------------------------------- 05-Feb-2005: ************ 00:54 ENE - Small blob-like front along streamer. 01:31 SE - Faint loop front that fades close to the inner edge of C3. 07:31 E - Faint, diffuse, and not-well-defined front partly superposed in the LOS with the slow development of a system of loops that started on previous day at ~ 06:30 UT). It is later apparently surpassed by following event. 13:31 ESE - Bright and big loop front. Trailing material. Gusty outflow well into next day. 18:30 E - Bright and elongated ragged loop front. Some infalling material in the tail. By 20:58 UT, the development of a faint loop front on E developing slightly toward ESE can be discerned in the trailing material of event reported to start at 13:31 UT. ---------------------------------------------------------------------------------- 06-Feb-2005: ************ 05:30 NW - Extremely faint though relatively big expanding loop front. Barely visible in C3. 09:54 E - Faint and small front that fades throughout C2. Infalling material. 12:54 SW - Diffuse jet-like front that quickly fades. 15:06 SE - Elongated and ragged structure. By 16:30 UT, a ragged loop front can be discerned superposed in the LOS developing a little bit more slowly. 19:31 WSW - Elongated and ragged loop front. ---------------------------------------------------------------------------------- 07-Feb-2005: ************ 03:30 WSW - Ragged front followed at 08:30 UT by a spray-like front. They both fade throughout C3. 14:30 ESE - Bright and ragged expanding front. GOES reported a long duration X-ray flare on S10E89 between 13:06 - 14:06 UT with peak emission at 14:06 UT. Multiple B- and C-class X-ray flares afterward on NOAA AR 10733 (in average around S06E80). Gusty emission all along the rest of the day on ESE-SE, most likely related to that activity. ---------------------------------------------------------------------------------- 08-Feb-2005: ************ 01:31 ESE - Spray-like front. 02:30 W - Extremely faint and elongated loop-like structure. Barely visible in C3. 06:30 N - Faint and very narrow loop-like front. 20:06 N - Extremely faint loop front developing slightly toward NNW. Difficult to give an exact time of first appearance. It fades throughout C3. ---------------------------------------------------------------------------------- 09-Feb-2005: ************ 04:06 N - Another extremely faint loop front starts to be visible. Difficult to give an exact time of first appearance. Some infalling material on NNW. Barely visible in C3. 10:54 N - Another extremely faint loop front starts to be visible developing slightly toward NNE. Difficult to give an exact time of first appearance. It fades throughout C3. Also some infalling material. 19:54 N - Another faint (expanding) loop front starts to be visible developing toward N. Difficult to give an exact time of first appearance. It fades throughout C3. 22:06 E - Very narrow and elongated loop-like structure developing toward ESE. It fades close to the inner edge of C3. ---------------------------------------------------------------------------------- 10-Feb-2005: ************ 00:30 E - Another very narrow and elongated loop-like structure developing toward ESE. It is followed by similar fronts at: 04:30, 05:54, and 11:30 UT. They all fade close to the inner edge of C3. In the last two cases, a ragged and diffuse loop front immediately follows a little bit to N. 04:30 WSW - Small blob-like front becomes discernible to N of streamer. It fades throughout C3. Infalling feature right above the W Limb. 04:54 SW - Faint and diffuse elongated loop-like structure that fades throughout C2. 06:30 NE - Diffuse and elongated loop-like structure. Difficult to establish association, if any, with loop front event following event at 05:54 UT. 18:54 SW - Very faint and elongated loop-like structure that apparently fades throughout C2. ---------------------------------------------------------------------------------- 11-Feb-2005: ************ 00:30 WSW - Faint and elongated feature barely N of streamer. Barely visible in C3. 02:54 ESE - Bright ragged loop front with structured interior. 12:06 ESE - Another bright ragged loop front with structured interior and trailing material. By ~ 18:54 UT, some small ragged fronts superposed in the LOS with the trailing material. 12:54 N - Very faint and diffuse jet-like front developing slightly toward NNE. It quickly fades. 16:30 NW - Jet-like front that quickly fades. ---------------------------------------------------------------------------------- 12-Feb-2005: ************ 01:31 ESE - In the trailing material of event reported to start at 12:06 UT on previous day, an elongated curved feature starts to be discernible (apparently, northern leg of a loop front that fades close to the inner edge of C3). 02:06 W - Extremely narrow loop-like feature developing toward WSW. 05:54 SE - Small ragged front becomes discernible in the trailing material. 12:06 WSW - A faint loop front becomes discernible in the slow development of a system of loops along the streamer that started on previous day. It fades throughout C3. 16:54 WSW - Another faint loop front (little brighter than theprevious one), immediately followed by a kind of reconexion event. 18:06 WNW - Very diffuse and extremely faint elongated loop front that fades throughout C2. 18:30 S - Very diffuse and faint elongated loop front that fades throughout C2. Another one follows at 20:30 UT. 23:54 NW - Jet-like front that quickly fades. ---------------------------------------------------------------------------------- 13-Feb-2005: ************ 01:31 SW - Ragged front along streamer. **** LASCO Data Gap between 04:30 - 06:30 UT. **** 06:54 SSW - Very diffuse and faint elongated loop front that fades in C2. 11:30 SE - Complex frontsided event formed by at least two-components: i) a diffuse front on ESE a little bit ahead (by 11:06 UT can already be guessed), and ii) an expanding loop front on SE (next images show the front reaching up to the SW Limb). The first front [i.e., i)] is first seen in C3 at 12:18 UT on ESE, while the other one is just appearing on SE. By 16:18 UT, the event considered as a whole spans ~ 103 deg, from PA 095-198. The whole event practically vanishes by 18:42 UT, without having reached the end of the C3 FOV. The mean plane-of-sky speed of the LE of front i) at PA 122 was ~ 454 km/sec, and of front ii) at PA 154 about 272 km/sec, showing an slight deceleration in both cases. GOES reported a C2.7 X-ray flare on NOAA AR 10733 (S11E09) between 10:28 - 10:51 UT with peak emission at 10:40 UT. EIT 195 running difference images show a brightening at 10:38 UT on the aforementioned AR (note that there is an EIT data gap between 09:00 - 10:28 UT) followed by an intensity disturbance (wave) developing toward W - SW - S - SE of the AR, stronger toward S and SE. The event considered as a whole did not reach an angular span of 120 deg to be considered as a complex partial halo (though one of its components did cross the S Pole). Its origin could be tracked back to the front side of the disk, very close to the central meridian. Therefore, the event has been determined as a complex frontsided event. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050213 11:30 W - Very faint and diffuse front. It is first seen in C3 at 12:18 UT, quickly fading afterward. Difficult to establish its association, if any, with the events described above. ---------------------------------------------------------------------------------- 14-Feb-2005: ************ E - Slow development of a relatively wide system of loops since late on previous day. The event reported to start at 12:54 UT seems to affect its evolution. Moreover, after that event, a clear inner twisted structure can be discerned (gradual event). 06:06 W - Very faint and diffuse loop front apparently preceded by an even fainter front that spans all above the SW limb. 12:54 E-S-W - Excess intensity on W Limb, and to a lesser extent on the S Pole. Also by that time, a not-well-defined front develops on E-SE, superposed in the LOS with the slow development of the system of loops on E-ESE. By 13:31 UT, a diffuse loop front can be discerned above the S Pole. GOES reported a C1.5 X-ray flare on NOAA AR 10733 (S11W05) between 11:52 - 12:06 UT with peak emission at 11:58 UT. 17:06 ENE - Diffuse and elongated loop-like feature followed by another one a little bit to S at 20:30 UT. They both fade very close to the inner edge of C3. ---------------------------------------------------------------------------------- 15-Feb-2005: ************ SE - Some ragged and not-well-defined loop fronts all along the day. 04:06 W - Faint ragged front. Infalling material. Difficult to give an exact time of first appearance. It fades throughout C3. 05:06 E - Extremely faint jet-like front followed at 07:54 UT by a very narrow spray-like front. Both features develop slightly toward ENE. By 08:30 UT, a faint ragged front can be discerned to S, in the aftermath of the gradual event reported on previous day. 10:54 WSW - A small blob-like front start to be discerned already half way to the end of the C2 FOV, fading throughout C3. 20:30 E - Jet-like front developing slightly toward ENE. 20:30 W - Very faint and diffuse wide loop front extending all the way to SW. By 20:58 UT, a diffuse loop front develops above the S Pole. They are both barely visible in C3. GOES reported a C1.1 X-ray flare on NOAA AR 10734 (practically at the center of the disk) between 19:28 - 20:05 UT with peak emission at 19:48 UT. ---------------------------------------------------------------------------------- 16-Feb-2005: ************ 04:30 E - Elongated and diffuse faint loop-like structure. It is followed at 06:54 and 08:06 UT by a couple of similar fronts, all of them developing slightly toward ENE. They all fade very close to the inner edge of C3. 06:54 SW - System of faint and diffuse expanding loop fronts. New loop system fronts continuously develop all along the day (in particular at 08:30 AND 12:58 UT). They all fade throughout C3. **** EIT Shutterless Run Segment #1 (in 304 A) --> 14:00 - 16:40 UT. **** **** Only about one C2 image/hour and no C3 images during the run. **** ---------------------------------------------------------------------------------- 17-Feb-2005: ************ 00:06 WNW - Diffuse loop front surrounded by a very faint front. The C2 Asymmetric occulting disk appears completely covered by 00:54 UT (though HALO the excess intensity characterizing the halo is very faint on E). The event is first clearly seen in C3 at 00:42 UT above the W Limb. By 02:42 UT the C3 occulting disk seems to be completely covered (as in C2, the halo is barely visible on E). The mean plane-of-sky speed of the LE of the event based on C3 data at PA 950 was around 900 km/sec (LE too faint and diffuse to have a precise measurement). GOES reported a C4.9 X-ray flare on NOAA AR 10734 (S03W24) late on 2005/02/16, between 23:29 - 23:53 UT with peak emission at 23:38 UT. The flare occurs just after a B4.7 X-ray-flare on NOAA AR 10735 (S10W03) between 23:03 - 23:19 UT with peak emission at 23:15 UT. EIT 195 images show the reconfiguration of loops nearby AR 10734 since around 22:24 UT. EIT 195 running difference images show a relatively strong brightening on AR 10734 at 23:36 UT. An extremely faint intensity disturbance can be seen afterward developing mainly toward NW of the AR. Between 01:13 - 03:24 UT (on 2005/02/17), a dimming region develops N of ARs 10734-10735. In summary, the event has therefore been determined as a faint asymmetric full halo event, frontsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050217. 05:54 E - Extremely narrow loop-like feature developing slightly toward ENE. It fades throughout C2. 09:06 W - Faint and diffuse loop front. By 10:30 UT a small blob-like front becomes discernible on SW. They fade throughout C3. 09:30 SE - Faint and ragged loop front along streamer that fades throughout C3. 18:06 W - Small blob-like front developing slightly toward WSW. Corresponding infalling material a little bit to N. 21:54 S - Diffuse jet-like front accompanied on SSW by a very faint and diffuse front that fades throughout C2. 23:30 W - Ragged loop front much brighter to S. It fades throughout C3. **** Note: Multiple B-class flares and one C2.3 X-ray flare **** **** on NOAA AR 10732 (around N15W90) since 20:56 UT. **** ---------------------------------------------------------------------------------- 18-Feb-2005: ************ **** Note: Multiple B- and C-class X-ray flares on NOAA AR **** **** 10732 all along the day (around N14W90). **** 04:30 S - Diffuse jet-like front. 14:30 W - Extremely faint loop front. 18:06 E - Diffuse and not-well-defined front that fades throughout C2, superposed in the LOS with the development of a system of loops (the system of loop starts to be discerned at ~ 17:30 UT). 20:54 SW - Bright and ragged loop front immediately followed by another loop front. Apparently, after the appearance at 22:30 UT on W of a faint and diffuse loop front, a diffuse and expanding loop front develops toward SW. ---------------------------------------------------------------------------------- 19-Feb-2005: ************ **** Note: Still multiple B-class X-ray flares on NOAA AR **** **** 10732 until around midday. **** 04:30 SW - Expanding loop fronts all above the W-SW-S limbs along the day. 11:06 W - Very bright loop front with structured interior. Some infalling blobs in the trailing material. Gusty outflow. GOES recorded a M3.3 X-ray flare from NOAA AR 10732 (N12W90) between 10:36 - 11:13 UT with peak emission at 11:01 UT. 22:30 W - In the aftermath of previous event, elongated ragged front that fades throughout C3. ---------------------------------------------------------------------------------- 20-Feb-2005: ************ 04:06 W - Couple of ragged fronts. Some infalling material afterward. 16:06 W - Initially bright ragged loop front developing with apparently two components. Source behind the limb. By around 18:06 UT, lot of small reconexion events in the trailing material. Infalling material. 17:30 E - Bright ragged loop front. 19:31 NNW - Small loop front that quickly fades. ---------------------------------------------------------------------------------- 21-Feb-2005: ************ W - Gusty outflow all along the day. **** LASCO Data Gap between 21:36 - 00:00 UT. **** ---------------------------------------------------------------------------------- 22-Feb-2005: ************ 10:54 WNW - Bright and extremely elongated expanding loop-like structure. 19:27 S - Kind-of faint half loop front. 20:27 W - Not-well-defined and diffuse front that fades in C2. 21:52 SE - Slow development of a loop front with structured interior. The excess intensity signaling the appearance of the event above the SE Limb can be discerned as early as 20:27 UT. Its development extends well into next day. ---------------------------------------------------------------------------------- 23-Feb-2005: ************ 03:54 S - Extremely faint, elongated, and expanding loop front (barely discernible); also barely discernible in C3 starting at 08:42 UT. 10:06 W - Ragged front that apparently fades throughout C2. **** EIT Shutterless Run Segment #2 (in 304 A) --> 12:00 - 14:40 UT. **** **** Only about one C2 image/hour and no C3 images during the run. **** 13:39 W - Ragged front. It fades throughout C3. 15:31 W - Elongated and expanding loop front developing toward WNW, much faster than previous event. Some small blob-like fronts afterwards all above the W Limb, also some infalling material (well into next day). ---------------------------------------------------------------------------------- 24-Feb-2005: ************ 01:31 W - Faint and very diffuse loop front brighter to S. It fades close to the inner edge of C3. 10:06 SE - Reconexion Event: small ragged front moving out and another one moving in. Separation point: ~ 3.2 solar radii at PA ~ 125. 16:24 SE - Small ragged front starts to be discernible at ~ 3.4 solar radii (PA ~ 125). ---------------------------------------------------------------------------------- 25-Feb-2005: Mostly quiet. ************ ---------------------------------------------------------------------------------- 26-Feb-2005: Mostly quiet. ************ 15:30 N Faint and diffuse loop front that quickly fades. It is followed at ~ 20:06 UT on NNE by a small and very faint blob-like front. ---------------------------------------------------------------------------------- 27-Feb-2005: ************ 00:30 NNE - Another very faint front. 10:34 W - Bright loop front followed at 11:06 UT by another loop front, which precedes a twisted structure (inner core). The second loop front and twisted structure develop more slowly than the outer loop front. They all develop toward WSW-SW. 18:30 NE - Jet-like front. 21:30 ESE - Bright and ragged loop front, preceded by a diffuse front that starts to be discerned as early as 19:54 UT. Trailing material. 22:30 NE - Another jet-like front. ---------------------------------------------------------------------------------- 28-Feb-2005: ************ 00:54 NE - Jet-like front that quickly fades. 06:06 W - Very narrow and elongated loop-like structure. 10:34 NW - Extremely faint, elongated, and diffuse loop-like structure. It fades throughout C2. **** No LASCO/EIT Observations between ~ 17:00 - 19:40 UT. **** 22:30 S - Very bright and wide loop front. Slight excess intensity above Complex the S Pole can be discerned since 22:06 UT. During its Partial development in C2, at least 2 components can be distinguished: Halo i) a wide ragged loop front developing mainly toward SW, and ii) a ragged loop front developing toward SSE, partly superposed in the LOS with the other loop front. By 23:54 UT, a relatively small loop front can be seen developing on SW (see event at 23:54 UT). GOES registered no significant X-ray activity during the time. Likewise, EIT 195 images show no significant activity on the disk. However, starting at ~ 22:36 UT, they do show signatures of a CME above the SW Limb, apparently originated on the backside, most likely the EIT counterpart of event first seen at 23:54 UT. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050228. 23:54 SW - Bright loop front develops just behind event reported to start at 22:30 UT as a three-part structure CME - Leading edge, cavity, inner core - (ballon-type). Couple of ragged fronts above the W Limb (around 00:54 and 01:54 UT -on next day-). By 02:54 UT (also on next day), faint and diffuse loop-like extensions can be discerned on S. Several ragged fronts follow during the day (2005/03/01) above the S Pole. Association to balloon type CME not clear. Several ragged fronts afterward all along the day all across the S Pole. EIT 195 images show no significant activity on the disk. However, starting at ~ 22:36 UT, they show signatures of a CME above the SW Limb, apparently originated on the backside of the Sun. ---------------------------------------------------------------------------------- 01-Mar-2005: ************ 00:30 NNW - Slow development of a system of expanding loops. New front system by 03:30 UT, which at least initially, moves apparently faster than the first one. 13:54 NW - Diffuse and not-well-defined elongated loop front. Difficult to give an exact time of first appearance. By the time, the slow development of a system of loops a little bit to S can be seen superposed in the LOS. By ~ 18:54 UT, a loop front starts to be discerned in the preexistent outflow. It is clearly seen in C3 starting at 20:18 UT. The development of the system of loops seems to be affected by that of the front at 18:54 UT. 20:59 W - Extremely narrow loop-like feature that fades throughout C2. ---------------------------------------------------------------------------------- 02-Mar-2005: KEYHOLE ************ 00:06 SE - Ragged front that fades throughout C3. 00:30 SW - Ragged front in the gusty outflow. The gusty outflow is present all along the day. 01:31 W - Narrow loop-like feature, followed by a similar one (though smaller) by 03:30 UT. Another one at 05:30 UT. ~Noon NW - The slow development of a system of loops reported on previous day starts to "blow-out" by around midday. 12:54 NNE - Extremely faint elongated loop-like structure that quickly fades. 17:30 NE - Very faint and diffuse jet-like front that quickly fades. 17:54 NW - Jet-like front. 23:06 NNW - Diffuse and ragged loop front. Excess intensity above the NNW Limb already present by 22:30 UT. It fades throughout C3. ---------------------------------------------------------------------------------- 03-Mar-2005: KEYHOLE ************ 02:30 SW - Very faint and diffuse front partly superposed in the LOS with a streamer. A kind of pseudo-continuous outflow follows all along the day. Couple of hours after the first front, starts to be discerned the slow development of a system of loops along the streamer (difficult to give an exact time of first appearance for this system of loops; by 06:54 UT the system is clear). 10:06 ENE - Ragged and diffuse lop front developing toward E. A structured ragged front superposed in the LOS, infalling material. 15:30 N - Diffuse jet-like front that quickly fades. ---------------------------------------------------------------------------------- 04-Mar-2005: KEYHOLE ************ SSW - Some outflow in the form of faint and diffuse loop fronts all along the day. 20:54 W - Diffuse loop-like front that fades throughout C2. 21:08 NE - Jet-like front that quickly fades. Another one on NNE. 22:06 ENE - Jet-like front developing toward E. ---------------------------------------------------------------------------------- 05-Mar-2005: KEYHOLE ************ 00:06 W - Elongated and diffuse loop-like feature that apparently fades throughout C2. 01:54 W - Ragged loop front. It fades throughout C3. 11:30 NNW - Very elongated and narrow feature that fades throughout C2. 13:54 W - Elongated loop-like feature developing slightly toward WSW. It fades throughout C3. 14:30 ESE - Faint and very diffuse front that quickly fades. ---------------------------------------------------------------------------------- 06-Mar-2005: KEYHOLE ************ 03:30 W - Ragged loop front. It fades throughout C3. 05:30 E - Elongated and expanding loop-like front. It fades throughout C3. 05:54 SE - Bright loop front followed by a cavity and a bright inner core (typical 3-part structure CME). EIT 195 recorded a backsided filament eruption between 05:24 - 06:24 UT. 17:54 W - Faint ragged loop front. Fainter extensions ahead extending to SW. Infalling material to S. 20:59 SE - Small ragged front. ---------------------------------------------------------------------------------- 07-Mar-2005: KEYHOLE ************ 02:54 NE - Elongated and very faint feature. It fades throughout C2. 06:30 SSW - Extremely faint elongated feature that quickly fades. 11:30 E - Faint ragged front that fades very close to the inner edge of C3. 13:54 W - Elongated loop-like feature followed at 17:06 UT by a similar (though much smaller) one. 18:06 ENE - Ragged front forms along streamer. Difficult to give an exact time of first appearance. ---------------------------------------------------------------------------------- 08-Mar-2005: KEYHOLE ************ 07:31 WSW - Very faint and diffuse loop front that quickly fades. 10:30 NNE - Elongated and narrow loop-like feature. It fades throughout C3. 13:31 E - Ragged front that fades close to the inner edge of C3. 20:30 W - Very narrow jet-like feature develops as an elongated and very narrow (slightly expanding) loop structure. Barely seen in C3. ---------------------------------------------------------------------------------- 09-Mar-2005: KEYHOLE ************ 02:06 E - Very faint and narrow expanding loop front. It fades close to the inner edge of C3. 02:54 W - Very faint and diffuse loop front that quickly fades. 07:31 W - Narrow and very faint loop-like front. **** Non-recoverable Data Gap due to Keyhole **** **** between 08:06 - 14:00 UT. **** **** ICAL01 (Intercalibration for EIT with CDS) **** **** between 14:00 - 15:20 UT. No LASCO Data. **** ---------------------------------------------------------------------------------- 10-Mar-2005: KEYHOLE ************ 00:54 W - Spray-like front developing slightly toward WSW. Expanding loop front toward W a little bit to N at 01:31 UT. Another expanding loop front follows at 05:06 UT. They all fade throughout C3. 12:06 E - Faint and diffuse elongated feature. It is followed at 14:54 UT by a faint and elongated loop-like structure. 20:30 W - Extremely faint and elongated loop front that fades throughout C2. 20:30 SW - A ragged blob-like front developing along a streamer starts to be visible (difficult to give an exact time). 23:30 NE - Long jet-like feature, clearly visible in C3 by 01:32 UT. ---------------------------------------------------------------------------------- 11-Mar-2005: KEYHOLE ************ **** EIT CCD bakeout between 2005/03/11 - 2005/03/31. **** **** NO EIT images during the bakeout. **** 01:31 NE - Elongated and expanding loop front a little bit to S of event reported to start at 23:30 UT on previous day. It fades throughout C3. 12:30 NE - Another elongated and expanding loop front. It fades throughout C3. 15:30 SE - Initially bright ragged loop front. **** LASCO Data Gap between 17:06 - 20:54 UT. **** ---------------------------------------------------------------------------------- 12-Mar-2005: KEYHOLE ************ 07:00 WNW - Very faint and ragged front that fades throughout C2. 13:48 NE - Elongated spray front. Faint extensions to S. 15:00 NW - Very faint and diffuse jet-like front that fades throughout C2. 17:00 WNW - Extremely faint front that fade throughout C2. It is followed at around 22:36 UT by another faint and ragged front. 17:24 ENE - Slow and expanding loop front with twisted interior and trailing material. Excess intensity ahead of the loop front can be seen since about one hour earlier. ---------------------------------------------------------------------------------- 13-Mar-2005: KEYHOLE ************ 09:12 WNW - Another faint and ragged front that fades throughout C2. A similar one at 13:24 UT. 10:24 SW - Slow development of a very faint and apparently structured feature. Difficult to give an exact time of first appearance. 16:00 WNW - Ragged loop front that fades very close to the inner edge of C3. Trailing material (gusty outflow). ---------------------------------------------------------------------------------- 14-Mar-2005: KEYHOLE ************ 07:48 W - Bright and wide loop front, followed by a cavity and a bright twisted inner core (typical 3-part structure CME). Trailing material. Some small ragged fronts follow later all along the day (e.g., clear ones at 13:48, 17:24, 18:12, and 21:12 UT). By ~ 23:12 UT a faint ragged front can be discerned developing slightly toward WSW. Gusty outflow into next couple of days. ---------------------------------------------------------------------------------- 15-Mar-2005: KEYHOLE ************ **** LASCO Data Gap between 00:48 - 13:36 UT. **** 14:00 ENE - Very faint and elongated front that fades throughout C2. 15:48 SE - Bright expanding loop front followed by a cavity and a bright inner core (typical 3-part structure CME). Gusty outflow. ---------------------------------------------------------------------------------- 16-Mar-2005: KEYHOLE ************ 17:48 SE - Very faint ragged loop front in the gusty outflow that followed the 3-part structure CME event on previous day. Barely visible in C3. ---------------------------------------------------------------------------------- 17-Mar-2005: KEYHOLE ************ 00:48 W - Ragged and diffuse front preceded by a couple of not-well-defined fronts late on previous day. They all fade close to the inner edge of C3. By the time, the slow development of a system of loops can be seen superposed in the LOS. 07:12 W - Ragged front superposed in the LOS with the slow development of the system of loops. 13:36 SE - Narrow and elongated feature followed at around 15:24 UT (difficult to precise) by a narrow and bright elongated loop- like structure. Gusty outflow afterward. ---------------------------------------------------------------------------------- 18-Mar-2005: KEYHOLE ************ 02:00 WSW - Slow expanding loop front followed by a system of expanding loops. 12:24 W - Couple of elongated loops start to be discernible. Some infalling material. 18:00 W - Ragged front developing slightly toward WNW. It fades throughout C2. ---------------------------------------------------------------------------------- 19-Mar-2005: KEYHOLE ************ 07:36 WSW - Small ragged front along streamer that fades in C2. 13:24 SE - Faint ragged loop front. It fades throughout C3. 18:24 WSW - Small raged loop front along streamer that apparently fades throughout C2. 20:48 WSW - Initially bright ragged front with diffuse and extremely faint extensions above the W Limb. It fades throughout C2. ---------------------------------------------------------------------------------- 20-Mar-2005: KEYHOLE ************ 02:12 WSW - Bright ragged loop front accompanied by a faint expanding loop front (first seen at 02:24 UT) that extends well above the SW Limb and seems to develop a little bit faster. They both fade throughout C3. 12:12 WSW - Another bright ragged loop front. 18:36 W - Faint and very narrow and elongated loop front. 23:12 WSW - Another bright ragged loop front. ---------------------------------------------------------------------------------- 21-Mar-2005: KEYHOLE ************ 05:12 NE - Very faint ragged front. **** LASCO Data Gap between 05:36 - 13:36 UT. **** 14:36 E - Wide and bright loop front, structured interior, and trailing material. Extremely faint extensions above the S Pole by 15:36 UT (they quickly fade out). By 16:48 UT, a ragged front develops in the trailing material. Gusty outflow. **** 21:42 UT --> Last LASCO C3 image before closing doors **** **** ahead of maneuvers on 2005/03/22. **** **** 21:48 UT --> Last LASCO C2 image before closing doors **** **** ahead of maneuvers on 2005/03/22. **** ---------------------------------------------------------------------------------- 22-Mar-2005: KEYHOLE - SOHO S/C Maneuvers (Roll back to 0 deg, station keeping) ************ **** LASCO doors closed. No LASCO Observations. **** ---------------------------------------------------------------------------------- 23-Mar-2005: KEYHOLE - LASCO doors closed until around 21:00 UT. ************ **** 21:36 UT --> First LASCO C2 image after S/C maneuvers on 2005/03/22. **** **** 21:41 UT --> First LASCO C3 image after S/C maneuvers on 2005/03/22. **** ---------------------------------------------------------------------------------- 24-Mar-2005: KEYHOLE ************ 02:24 N - Extremely faint front. Not discernible in C3. 14:00 NW - Ragged loop front. By 16:48 UT, kind of reconexion event in the trailing material: ragged loop coming out, and corresponding infalling material a little bit to S. ---------------------------------------------------------------------------------- 25-Mar-2005: KEYHOLE ************ 04:00 NNE - Extremely faint front starts to be discernible in C2 half way to the end of the FOV. Difficult to precise the exact time of first appearance. 16:24 E - Diffuse jet-like front that quickly fades. 21:36 NNW - Extremely faint loop front starts to be discernible in C2. Difficult to precise the exact time of first appearance. ---------------------------------------------------------------------------------- 26-Mar-2005: KEYHOLE ************ 01:36 NE - Very faint loop front precedes the development of a faint system of slowly expanding loops. 02:24 NNW - Faint and asymmetric expanding loop front starts to be seen at around 3.7 solar radii. Some infalling material later on NW. 16:36 ESE - Small ragged front along streamer. ---------------------------------------------------------------------------------- 27-Mar-2005: KEYHOLE ************ 06:36 NE - In the trail of event reported to start at 01:36 UT on previous day, a faint and elongated loop front becomes discernible developing apparently more rapidly. 08:24 WNW - Very faint and diffuse loop front that fades throughout C2. 16:24 NNE - Jet-like front followed at 17:36 UT by another jet. Small ragged front to N followed by an elongated and expanding loop front at ~ 19:48 UT. ---------------------------------------------------------------------------------- 28-Mar-2005: KEYHOLE ************ 03:48 N - Small ragged front. It fades throughout C3. 07:36 E - Ragged front that fades very close to the inner edge of C3. 17:12 E - Very faint ragged front that fades throughout C2. 17:36 NW - Small and faint loop front that quickly fades. 18:00 ESE - Ragged loop front with apparently twisted inner core. Extremely faint extensions above the E Limb. Developing missed in the data gap. 19:36 SW - Expanding loop front. Development missed in the data gap. **** LASCO Data Gap between 21:00 - 24:00 UT. **** ---------------------------------------------------------------------------------- 29-Mar-2005: KEYHOLE ************ **** LASCO Data Gap between 00:00 - 08:24 UT. **** 11:24 W - Extremely faint and diffuse elongated loop-like feature that fades throughout C2. 12:48 ENE - Ragged loop front developing toward E. It fades throughout C2. 12:48 SW - Faint, diffuse, and elongated spray-like front. It fades throughout C3. 14:36 W - Diffuse jet-like front. 17:24 ENE - Another ragged loop front developing toward E. It also fades throughout C2. ---------------------------------------------------------------------------------- 30-Mar-2005: KEYHOLE ************ 04:12 SW - Faint, diffuse, and elongated loop-like structure. It fades throughout C3. 13:36 W - Faint, diffuse, and elongated loop-like feature. 23:36 W - Fa int and diffuse loop front brighter to N. It fades throughout C3 (very faint). ---------------------------------------------------------------------------------- 31-Mar-2005: KEYHOLE ************ 02:36 ENE - Small front starts to be discernible at ~ 3.16 solar radii (PA ~ 73). By 03:36 UT, on ESE, a very faint and diffuse front that quickly fades develops. 05:36 ENE - Very faint ragged front that fades throughout C2. ================================================================================== 01-Apr-2005: ************ 07:50 W - Very faint and diffuse narrow loop front. It fades throughout C2. 15:50 NE - Faint and diffuse elongated loop front. It fades throughout C2. 20:50 E - Another faint and elongated loop-like feature that fades throughout C2. ---------------------------------------------------------------------------------- 02-Apr-2005: ************ 00:06 N - Faint and diffuse elongated loop-like feature developing toward NNW. 00:50 W - Diffuse and faint elongated loop-like feature followed by a very faint ragged front that starts to be visible at ~ 4 solar radii (PA ~ 250, @ 02:50 UT). 12:06 SW - Ragged and elongated loop front with structured interior. System of loop fronts in the trailing material. ---------------------------------------------------------------------------------- 03-Apr-2005: ************ 00:26 NE - Jet-like front that quickly fades. 00:50 N - Faint and diffuse front developing toward NNW. It quickly fades. 00:50 SW - Very narrow and elongated loop-like feature. By 01:50 UT, a diffuse and narrow loop-like front develops to N. They both fade throughout C2. 17:50 WSW - Small and faint blob-like front starts to be discernible. ---------------------------------------------------------------------------------- 04-Apr-2005: ************ 07:50 ENE - Faint and elongated front. It fades troughout C3. 11:06 S - Diffuse loop front preceding a couple of big and bright ragged loop fronts. Small ragged front on SE by 15:50 UT. 16:26 NW - Kind-of "half" loop front. Another one starts to be visible by 20:06 UT. ---------------------------------------------------------------------------------- 05-Apr-2005: ************ 06:50 W - Diffuse front that quickly fades. 09:26 NW - Very faint and diffuse loop front. By 11:26 UT a faint and expanding loop front starts to be discernible at ~3.35 solar radii (PA ~315). A jet-like front develops by 14:50 UT at a PA that matches the PA of the northern leg. Reconexion event on NNW by 18:06 UT (pair formation). 12:50 SE - Diffuse front preceding the development of a bright loop front with twisted interior and trailing material. Gusty outflow in the form of small ragged fronts precedes the whole event. ---------------------------------------------------------------------------------- 06-Apr-2005: ************ 00:50 W - Very faint and diffuse small front that quickly fades. 01:50 N - Small jet-like front developing slightly toward NNE. 04:26 NW - Blob like front. It fades throughout C3. **** No LASCO Observations between 11:00 UT - 12:20 UT **** **** due to ICAL01 (Intercalibration for EIT with CDS). **** 12:26 ESE - Narrow and elongated loop front. 16:06 ESE - Ragged front that fades throughout C3. 18:06 N - Very faint expanding loop front starts to be discernible, though it is difficult to precise the time of first appearance. By around 00:06 UT on next day, a similar front develops on NNE. 21:26 WSW - Slow development of a system of faint loops along streamer. Difficult to give an exact time of first appearance. ---------------------------------------------------------------------------------- 07-Apr-2005: ************ 03:26 ESE - Ragged front that quickly fades. 11:50 NNE - Diffuse, narrow, and very elongated loop front. 13:27 E - Ragged front developing slightly toward ENE. 18:50 ESE - Very faint and diffuse ragged front that fades throughout C2. ---------------------------------------------------------------------------------- 08-Apr-2005: ************ 00:06 NE - Faint blob-like front starts to be discernible. Another one behind becomes discernible by 02:26 UT. They both fade throughout C3. 06:50 E - Very faint and diffuse front that quickly fades. 09:26 NNW - Jet-like front. 10:50 E - Another small front that quickly fades. 11:50 SSW - Jet-like front. 12:26 WSW - Diffuse front preceding another diffuse front at ~ 13:50 UT, along the streamer. By that time, the slow development of a system of ragged and faint loops along the streamer starts to be discernible. 14:26 NNW - Jet-like front followed by a very narrow and elongated loop front (jet-like) by 15:26 UT. ---------------------------------------------------------------------------------- 09-Apr-2005: ************ 00:06 ENE - Faint and diffuse front that quickly fades. 00:26 NNW - Very faint jet-like front. 02:26 N - An extremely faint and diffuse front most clearly visible above the N Pole (and by 3:34 UT above the W limb) develops and in the following frames seem to surround completely the C2 occulting disk. Nothing can be discerned in C3. 08:06 W - Wide and ragged loop front. 10:26 E - Spray-like front followed at 15:26 UT by another one (much smaller and developing slightly toward ENE). 12:06 SE - Narrow loop front (fan-like). 13:50 W - Another wide and ragged loop front (though brighter than the one at 08:06 UT and apparently developing faster). A faint and ragged expanding loop front starts to develop by 15:06 UT, superposed with the northern leg of the wide loop front (on NW). 19:50 ESE - Faint and elongated expanding loop front. ---------------------------------------------------------------------------------- 10-Apr-2005: ************ 05:50 ESE - Faint spray-like front preceding a bright loop front with apparently twisted interior (first appearance by 07:27 UT). 19:27 W - Very faint, narrow and diffuse spray-like front. It fades throughout C2. 21:26 SSW - Very faint and diffuse wide asymmetric loop front developing very slowly. Difficult to give an exact time of first appearance. System of faint loops develop early on next day on SW. ---------------------------------------------------------------------------------- 11-Apr-2005: ************ 01:27 SSW - Very faint and diffuse front. It fades throughout C2. 16:26 WSW - A small brightening can seen along the streamer. By 17:50 UT, an extremely faint and ragged front follows. It is barely visible in C3. 18:26 ENE - Elongated and narrow (fan-like) loop front. It fades throughout C2. ---------------------------------------------------------------------------------- 12-Apr-2005: ************ WSW - Gusty outflow along the streamer in the form of ragged fronts since early in the day. The slow development of a faint system of loops can be seen superposed in the LOS also since the beginning of the day. 00:26 SW - A faint and asymmetric ragged front starts to be visible partly superimposed with the gusty outflow on WSW. It fades throughout C3. 06:50 WSW - A faint and expanding ragged front starts to be discernible in the gusty outflow (though it is difficult to precise when it is first seen). Another one seems to follow by 10:50 UT. 16:26 SW - Couple of faint ragged fronts across the SW Limb (though it is difficult to precise when they are first seen). They fade throughout C3. 20:50 E - Elongated and diffuse loop front preceding a brighter elongated and also narrow elongated loop at 21:26 UT. They both fade throughout C3. ---------------------------------------------------------------------------------- 13-Apr-2005: ************ 07:50 SE - Faint and elongated (fan-like) loop front. 17:26 NNW - Diffuse jet-like front. 21:26 E - Elongated and expanding (toward ENE) loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 14-Apr-2005: ************ 02:26 E - Very faint and diffuse asymmetric loop front. 12:06 SW - Diffuse ragged front. **** LASCO Data Gap between 13:50 - 17:50 UT. **** ---------------------------------------------------------------------------------- 15-Apr-2005: ************ 04:50 ESE - Faint and diffuse ragged front. 08:50 NW - Very faint expanding loop front. 15:26 E - Faint ragged loop front. It fades throughout C2. Gusty outflow. 16:26 NW - Jet-like front. ---------------------------------------------------------------------------------- 16-Apr-2005: ************ 02:06 E - Ragged loop front. It fades close to the inner edge of C3. 08:06 NW - Elongated and narrow loop front that fades close to the inner edge of C3. 04:26 E - Faint and elongated front developing slightly toward ENE. It quickly fades. 09:06 E - Ragged loop front. It fades close to the inner edge of C3. 14:06 SE - Extremely faint front expanding toward the S Pole. It fades throughout C2. 16:50 E - Another ragged loop front. It fades throughout C3. 22:06 E - Not well definded loop front. It fades throughout C2. **** NOTE: **** E Limb activity related to B-class X-ray activity on E Limb during the day. ---------------------------------------------------------------------------------- 17-Apr-2005: ************ 02:06 E - Bright ragged loop front. It fades throughout C3. GOES recorded a C3.3 X-ray flare on S12E86 between 01:34 - 01:52 UT with peak emission at 01:44 UT. 06:50 NE - Kind-of reconexion event: A faint loop front expanding out and corresponding infalling material. Difficult to give an exact time of first appearance. 10:26 SSW - Very elongated, narrow and diffuse loop front. It fades throughout C2. 11:26 E - Faint and diffuse front preceding at 13:27 UT a bright loop front on ESE. Some gusty outflow. GOES recorded a C1.2 X-ray flare on NOAA AR 10752 (N03E09) between 12:12 - 12:33 UT with peak emission at 12:24 UT, and a C2.1 X-ray flare on S12E81 between 12:42 - 12:55 UT with peak emission at 12:49 UT. 18:50 NW - Diffuse and elongated loop front. It fades throughout C3. 21:26 ESE - Bright loop front and trailing material. GOES recorded a C4.6 X-ray flare on NOAA AR 10755 (S12E76) between 20:46 - 21:15 UT with peak emission at 21:07 UT. Gusty outflow into next day. 22:06 WSW - Faint and diffuse front that quickly fades, folllowed at 23:26 UT by an elongated jet-like front a little bit to S. ---------------------------------------------------------------------------------- 18-Apr-2005: ************ 00:06 NE - Kind-of reconexion event: a faint asymmetric loop front coming out and corresponding infalling material. Difficult to give an exact time of first appearance. 09:06 NW - Faint curved feature that fades close to the inner edge of C3. 09:26 NNE - Faint blob-like fronts. They fade throughout C3. 13:27 W - Elongated loop-like fetaure developing slightly toward WSW. It fades throughout C3. 18:06 WNW - Jet-like front. 18:26 E - In the gusty outflow present since event on previous day at 21:26 UT, a faint ragged loop front develops. It fades throughout C3. More gusty outflow in the form of small and ragged fronts. ---------------------------------------------------------------------------------- 19-Apr-2005: ************ 12:26 WNW - Bright ragged loop front and twisted trailing material. 17:50 WSW - Very faint and diffuse front that fades throughout C2. 17:50 N - Couple of faint blob-like fronts. They fade in C3. 22:06 E - Bright and wide loop front. Very faint extensions toward N. The mean plane of sky speed at PA 92 was ~ 741 km/sec showing practically no acceleration (based on C3 data). GOES reported a B8.0 X-ray flare on NOAA AR 10755 (S12E57) between 21:41 - 22:45 UT with peak emission at 22:17 UT. EIT 195 running difference images show a big CME starting at 21:36 UT around the AR 10755. A strong brightening can be seen on the AR by 22:12 UT. By that time it can also be discerned a rather circular intensity disturbance (wave) moving away from the AR (with epicenter on the AR). ---------------------------------------------------------------------------------- 20-Apr-2005: ************ 03:26 E - In the aftermath of event reported to start at 22:06 UT on previous day, a faint and expanding ragged loop front develops. 05:26 SW - Extremely faint reconexion event at PA ~ 236 (around 3.8 solar radii). Due to its faintness, it is difficult to give an exact time of first appearance. The infalling feature is barely discernible. The outward moving one fades throughout C3. 08:26 W - Diffuse and faint spray-like front. It fades close to the inner edge of C3. 11:26 E - Extremely faint and diffuse front that quickly fades. ---------------------------------------------------------------------------------- 21-Apr-2005: ************ 00:06 W - Very diffuse and ragged front precedes the development of a bright and ragged loop front (a little bit to S) that starts at around 00:26 UT. By 03:26 UT a thin and bright feature can be discerned in the trailing material. 07:50 E - Faint and diffuse jet-like front that quickly fades. 15:50 SW - Extremely faint ragged front starts to be discernible half way to the end of the C2 FOV. It fades in C3. Due to its faintness it is difficult to give an exact time of first appearance. ---------------------------------------------------------------------------------- 22-Apr-2005: ************ 00:26 ESE - Slow development of a system of faint loops. 02:26 S - Very faint expanding loop develops above the S Pole. 02:26 WSW - Very faint and diffuse front that quickly fades. 06:26 ESE - Bright loop front moving much faster than the system of loops reported to start at 00:26 UT. Very faint extensions above the E Limb. EIT 195 running difference images show signatures of a CME above the SW Limb starting at around 05:48 UT, apparently originated behind the limb. 07:27 NW - Very thin and elongated loop front. 09:50 S - Very faint expanding loop front followed by a similar one on SSE at ~ 12:06 UT. ---------------------------------------------------------------------------------- 23-Apr-2005: ************ 01:27 ESE - Faint and not-well-defined front followed at ~ 02:50 UT on E by an apparently twisted feature. Slow development of a system of faint loops afterward. Event barely discernible in C3. 05:26 NW - Bright and elongated loop front. It fades throughout C3. 12:50 NNW - Several faint and ragged blob-like fronts. Some more later along the day. They all fade throughout C3. 20:06 W - Extremely faint loop front that fades throughout C2. ---------------------------------------------------------------------------------- 24-Apr-2005: ************ 02:50 NW - Very faint, diffuse, and ragged front preceding a diffuse and rather elongated feature at ~ 04:06 UT, the latter expanding toward N. Difficult to say whether the diffuse front at 02:50 UT is part of the same elongated feature starting at 04:06 UT. 08:50 ENE - Very faint loop front. Development missed in the following data gap. **** Non-recoverable data gap between 09:36 - 16:00 UT apparently **** **** due to a LEB (LASCO Electronic Box) memory error. **** 16:26 NNE - Apparently twisted trailing material of an event that started during the data gap. An elongated and expanding loop front can be seen by the time developing in C3. 16:26 ENE - Gusty outflow that most likely started during data gap. 18:06 ENE - The slow development of a system of faint loops can be seen superposed in the LOS with the gusty outflow. It is difficult to give an exact time of first appearance. By around 04:26 UT on next day an expanding twisted structure can be discerned. 18:26 E - Faint loop front starts to be visible already half way to the end of the C2 FOV. ---------------------------------------------------------------------------------- 25-Apr-2005: ************ 04:26 ENE - Expanding twisted structure embedded in the preexistent outflow. Difficult to give an exact time of first appearance. 10:26 NNE - Ragged and apparently twisted small feature, just a little bit to N of the expanding twisted feature reported to start at 04:26 UT. 11:06 SW - Jet-like front that quickly fades. 13:50 SW - Bright and elongated asymmetric loop front (spray-like) a little bit to N of the jet. It fades throughout C3. 19:50 SW - Bright, elongated, and very thin loop-like front. Faint expanding extensions to N. 23:06 S - Diffuse and wide loop front just appearing above the S Pole. Partial A clear and well defined front can already be seen by 23:50 UT. Halo Couple of faint and diffuse fronts follow later, during the first hours of 04/26. The bulk of the event spans in C2 at 01:27 UT (on 04/26) about 173 deg (from PA 107 - 280). The event was first seen in C3 on 04/26 at 01:42 UT. The angular span is kept during its evolution in C3. The mean plane-of-sky speed of the LE of the event (based on C3 data) at PA 206 was ~ 330 km/sec, showing practically no acceleration. EIT 195 images show the eruption of a filament on 2004/04/25 on the SW quadrant (very close to the limb), associated with the C2/C3 event. In particular, the filament begins to rise by ~ 17:24 UT, initially very slowly. By 21:12 UT, some faint post event loops start to be seen. The EIT 304 image taken on 04/25 at 19:19 UT clearly shows the filament already above the SW Limb. On the other hand, GOES reported no significant X-ray activity by the time. In summary, the event has therefore been determined as a partial halo CME, at least partly frontsided, associated with a filament eruption. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050425. ---------------------------------------------------------------------------------- 26-Apr-2005: ************ S - Several faint and diffuse fronts follow behind the LE of the Partial Halo reported to start at 23:06 UT on previous day. 11:50 S - Faint and wide system of expanding loop fronts. The development continues through the end of the day. They all fade throughout C3. 20:06 SW - Bright and very elongated loop front with apparently twisted interior. It fades throughout C3. EIT 195 images show the ejection of material above the SW limb starting at around 19:36 UT. The EIT signature could also be related to event reported to start at 00:50 UT on next day. 20:26 W - Jet-like front. ---------------------------------------------------------------------------------- 27-Apr-2005: ************ 00:50 SW - Expanding and ragged loop front superposed in the LOS with event reported to start at 20:26 UT on previous day. Some expanding ragged fronts follow. Difficult to disentangle the different features that almost continuously show up. 01:50 SSW - Faint expanding loop front partly superposed with event reported to start at 00:50 UT on SW. The event at 00:50 UT develops faster. 05:50 SE - Wide and bright ragged loop front. EIT 195 images show a filament-based eruption from around W edge of NOAA AR 10756 between 05:00 - 07:13 UT. 08:50 W - Faint ragged front. Difficult to disentangle it from other features under development by the time. 12:26 ESE - Extremely faint and diffuse front, barely discernible. EIT 195 images show eruption from W edge of NOAA AR 10756 between 11:36- 13:25 UT. 13:27 NNE - Faint spray-like front that fades throughout C2. 16:04 ESE - Bright and slightly asymmetric ragged front preceded by a diffuse an elongated brightening. It fades throughout C3. 23:06 WSW - Faint and diffuse (small) loop front that fades throughout C2. ---------------------------------------------------------------------------------- 28-Apr-2005: ************ 00:06 SE - System of expanding loop fronts. Inner material apparently pushing the outer fronts. EIT 195 running difference images show by the time a tenuous signature of a CME above the SE limb. 02:26 SW - Bright and ragged loop front with structured interior. It moves much faster than the event developing on SE. The event is preceded by a very faint front on SSW that is first inferred at around 23:50 UT on previous day. By 03:50 UT, a system of loops develops behind the main front. 12:50 SE - Ragged front starts developing in the trailing material of event at 00:06 UT. By 14:26 UT, a system of expanding loops starts to be visible above the S Pole extending all the way above the SE Limb. No significant X-ray activity by the time. ---------------------------------------------------------------------------------- 29-Apr-2005: ************ 06:26 SE - Bright and ragged front followed at 07:27 UT by another ragged front, wider, which extends up to above the E Limb. Thay fade throughout C3. EIT 195 shows CME signatures on SE (ejecta heads almost due S), coming out from behind the Limb, between 05:36 - 06:48 UT. 10:50 E - Bright and wide ragged loop front with structured interior. EIT 195 shows signatures of a CME from behind the limb between 08:48 - 11:00 UT. 20:06 SE - Ragged loop front. Gusty outflow well into next day. Barely visible in C3 (lost in the trailing material of previous event). ---------------------------------------------------------------------------------- 30-Apr-2005: ************ ESE - Couple of ragged fronts discerned in the gusty outflow along the day (e.g., around 03:34, 08:06, and 10:26 UT). 08:06 NE - Diffuse and elongated spray-like front. It fades close to the inner edge of C3. 14:06 S - Very faint and diffuse front all across the S Pole. By 14:26 UT, (HALO) another similar front develops on NW, the C2 occulting disk being fully covered by the whole event considered as one by 15:06 UT. The second front is first seen in C3 at 16:18 UT, above the NW Limb. By 17:18 UT the C3 occulting disk seems to be completly covered. The event fades half way to the end of the C3 FOV, by around 22:18 UT. EIT 195 images show a brightening on NOAA AR 10757 starting at 10:24 UT and followed by a loop expansion toward S (also dimming region to S of area between ARs 10757 and 10756). GOES reported a B5.0 X-ray flare from NOAA AR 10757 (S08W15) between 10:11 - 10:19 UT with peak emission at 10:15 UT. Difficult to establish the association, if any, with the signatures observed in C2. ================================================================================== 01-May-2005: ************ 00:50 S - Faint and diffuse brightening shows up spanning all above the E (HALO) Limb, S Pole, and W Limb. It develops at the time of next frame (01:27 UT) as a Full Halo CME. The event is first seen in C3 at 01:42 UT almost covering the occulting disk. In next frame, i.e. at 02:18 UT, the event develops as a nicely symmetric full Halo CME. The mean plane-of-sky speed of the LE of the event, at different position angles is as follows (based on C3 data): . PA 000: ~ 515 km/sec . PA 090: ~ 523 km/sec . PA 180: ~ 600 km/sec (LE as the outermost feature of the diffuse structure -shock?-). . PA 270: ~ 815 km/sec (LE as the outermost feature of the diffuse structure -shock?-). . PA 270: ~ 425 km/sec (LE as of the structure coming behind the diffuse front). GOES only reported a couple of B-class X-ray flares by the time from NOAA AR 10757: - a B5.3 (S06W25) between 00:34 - 00:43 UT peaking at 00:38 UT, - a B7.0 (S06W26) between 01:03 - 01:29 UT peaking at 01:18 UT. On the other hand, EIT 195 images do not show any signature of a frontsided event. Therefore, based on the relative low importance of the X-ray activity by the time and the lack of signatures on the visible side of the disk as observed by EIT, the event has been determined as a Full Halo CME, most probably backsided. 09:50 E - Faint intensity brightening preceded by an extremely faint and diffuse front that extends up to above the S Pole. The C2 occulting disk seems to be completely covered by 10:06 UT. The event is so faint that fades throughout C2. No significant X-ray activity recorded by GOES by the time nor signatures on EIT 195. 15:50 W - Faint and very diffuse front that fades throughout C2. 19:50 E - Very faint and diffuse brightening on E. The C2 occulting disk seems to be covered completely by 21:26 UT. The event is so faint that fades then throughout C2. No significant X-ray activity by the time. ---------------------------------------------------------------------------------- 02-May-2005: ************ 05:26 NNW - Bright and asymetric loop front first seen in C2 above the NNW (HALO) Limb is followed at 05:50 UT by a rather wide loop-like feature spanning all the way above the E, N, and W limbs, and therefore superposed on NNW with the asymetric loop front. By that time, Very faint and diffuse extensions above the S Pole close the circle. By 06:26 UT, the faint extensions on S are barely discernible already close to the end of the C2 FOV, while the multiple (2) event completely cover the occulting disk, showing up as an asymmetric full Halo CME. The complex event is first seen in C3 at 06:18 UT, above the NW limb. By 06:42 UT the faint extensions on S are discernible, the C3 occulting disk being covered by the multiple (2) event structure by 08:18 UT. The mean plane-of-sky speed of the LE of the complex event at PA 0 was ~ 650 km/sec showing practically no acceleration. Visual inspection of the corresponding moving seems to indicate that the 2 components have slightly different speeds. GOES reported no significant X-ray activity by the time, nor relevant activity was revealed by EIT 195 images. Therefore, and based on the lack of evidence of frontsided activity, the event has been determined as a complex (multicomponent) asymetric full Halo CME, backsided. 07:50 ESE - Faint expanding loop fronts in the Halo aftermath. They fade throughout C3. 12:50 ENE - Elongated and bright ragged loop front. Some trailing material. It fades throughout C3. 13:27 W - Diffuse brightening preceding the development of a bright loop front with twisted interior and trailing part. Mean plane-of-sky speed at PA 270: 317 km/sec, slightly accelerated. 21:26 NE - Diffuse loop front completely surpassed by the following event before reaching the end of the C2 FOV. 22:26 ESE - Very bright and wide loop front. Another structure follows by ~ 23:26 UT, moving apparently faster. Its brighter part develops toward ENE. Trailing material on ENE. Streamer on N pushed toward the N Pole. Both events seem to merge in the C3 FOV. Mean plane- of-sky speed at PA 90: 931 km/sec, showing acceleration. GOES reported a C8.0 X-ray flare (LDE) on NOAA AR 10758 (S05E90) between 21:13 - 01:07 (+1) UT with peak emission at 22:48 UT. ---------------------------------------------------------------------------------- 03-May-2005: ************ 01:27 W - Extremely narrow loop front (almost jet-like) develops surrounded by a faint and expanding loop-like front. It fades throughout C3. Small ragged fronts all above the W limb along most of the rest of the day with some infalling material (sort of "reconexion" events). 04:26 ENE - Expanding loop front follows in the trailing material at ENE of the event reported to start at 22:26 UT on previous day. Some small ragged fronts afterward. 05:50 E - Ragged and very narrow loop front developing slightly toward ENE in the trailing material of the event reported to start at 22:26 UT on previous day. 14:26 ESE - Bright and very narrow loop-like front that fades throughout C3. 17:50 NE - A diffuse and wide expanding loop front starts developing above Partial the NNE limb, preceded by a brightening to S (on ENE) already Halo visible at 17:06 UT. The initial brightening is first seen in C3 at 18:42 UT above the ENE Limb, while the diffuse expanding loop makes its appearance above the C3 NNE limb at 19:42 UT. Close inspection of the corresponding C3 movie seems to indicate that in fact we are in the presence of 2 different events, which combined adopt the appearance of a partial halo CME. The mean plane-of-sky speed for both events is as follows: i) for the structure first seen on NNE: ~ 445 km/sec at PA 12, and ii) for the structure first seen on ENE: ~ 657 km/sec at PA 65. GOES recorded no significant X-ray activity by the time nor EIT 195 images show evidence of frontsided activity. The event has therefore been determined as a complex (apparently multi- component) partial halo CME, backsided. ---------------------------------------------------------------------------------- 04-May-2005: ************ 06:53 WSW - Very faint and diffuse loop front that quickly fades. 13:54 ESE - Very narrow front preceding at ~ 14:29 UT a bright ragged front. The event fades throughout C3. 16:27 NE - Diffuse and very elongated fan-like front. It quickly fades in C3. 18:38 ESE - Faint system of expanding loops. They fade very close to the inner edge of C3. 22:54 WSW - Initially bright loop front that fades close to the inner edge of C3. A system of slow loops starts then to be discernible at ~ 01:54 UT on next day. ---------------------------------------------------------------------------------- 05-May-2005: ************ 05:54 E - Faint and diffuse ragged front. It fades very close to the inner edge of C3. 10:30 WNW - Very faint expanding loop front developing toward W. It fades throughout C2. 18:30 E - Asymetric and very faint ragged loop front preceded event at 20:30 UT. 20:30 E - Very bright and wide loop front. Faint asymetric extensions surround the C2 occulting disk by 21:54 UT. The bright front is first seen in C3 above the E Limb at 21:18 UT. The faint and asymetric extensions seem to cover the C3 occulting disk by 00:18 UT on next day (though very faint, quickly fading). The mean plane-of-sky spped of the LE of the bright front at PA 90 was ~ 1210 km/sec, showing practically no acceleration. GOES reported no X-ray events associated to the event. EIT 195 images show signatures of a big CME from behind the limb between 18:48 - 21:48 UT. Tops of post-flare arcade start to be visible at 23:12 UT. 20:58 W - Bright and elongated feature develops as a ragged loop front. It fades throughout C3. GOES reported a C7.8 X-ray flare from NOAA AR 10756 (S04W67) between 20:09 - 20:27 UT with peak emission at 20:20 UT. EIT 195 images show a brightening on AR 10756 followed by ejection of material toward NW. One footpoint of the CME appears to some 15 - 20 deg N of the AR. ---------------------------------------------------------------------------------- 06-May-2005: ************ 02:30 WNW - Spray-like front surpassed by following event (03:30 UT) practically before reaching the end of the C2 FOV. 03:30 WNW - Bright ragged loop front with faint and diffuse loop-like extensions all around the bright loop. Very bright in C3. GOES reported a C9.3 X-ray flare from NOAA AR 10756 (S04W71) between 03:05 - 03:21 UT with peak emission at 03:14 UT. 06:06 ENE - Apparently, kind of reconexion event (very faint). Difficult to give an exact time of first appearance. 10:30 W - Diffuse and ragged loop front developing slightly toward WSW. By 11:54 UT is already surpassed by following event (11:30 UT). 11:30 WNW - Initially bright and small front just appearing. It develops as a bright ragged loop front with faint and diffuse loop-like extensions all around the bright loop. GOES reported a M1.3 X-ray flare from NOAA AR 10756 (S04W76) between 11:11 - 11:35 UT with peak emission at 11:28 UT. 17:28 SE - Complex event. A Partial Halo event was first seen in C2 at Partial 17:28 UT as a bright and wide loop front (hereafter Event #1) Halo above the SE Limb. By 17:54 UT, faint and diffuse extensions & can be seen above the W Limb and N Pole (Event #2). The Event HALO #2 surrounds the C2 occulting disk by 18:06 UT. The Event #1 was first seen in C3 at 17:42 UT appearing above the SE Limb, while the Event #2 shows up at 18:18 UT just above the N Pole. The Event #2 surrounds the C3 occulting disk by 19:12 UT. The Event #1 spans ~ 185 deg by 21:18 UT (LE almost at the end of the C3 FOV), from PA 25 - 210. The mean plane-of-sky speed of the LE of Event #1 (based on C3 data) at PA 108 was ~1100 km/sec, showing an slight deceleration. As for the Event #2, the mean C3-plane-of-sky speed of the LE at PA 355 was about 675 km/sec, showing practically no acceleration. GOES reported a long duration C8.5 X-ray flare on NOAA AR 10758 (S09E29) between 16:03 - 18:09 UT with peak emission at 17:05 UT. EIT 195 images show a strong brightening on the aforementioned region starting at 16:12 UT. A big change in the magnetic field topology in and around the AR between the frames taken at 16:24 and 17:21 UT (no frames in between) can be observed. By 17:21 UT post-flares loop begin to appear as well as dimming regions to N and S of the AR. By that time, EIT 195 running difference images show a huge intensity disturbance all across the eastern hemisphere. The signatures observed in EIT clearly indicate the association of the X-ray event with the Event #1 observed by LASCO C2/C3. It is difficult to say whether the Event #2 is part of the Event #1 or signature of an apparently backsided CME with source region on the northern hemisphere. Observation of the evolution of the complex event in C3 seems to indicate that the latter does correspond to a different event. In summary, the Event #1 has therefore been determined as a Partial Halo CME, frontsided, associated with a long duration C-class X-ray flare on NOAA AR 10758. A faint full halo CME (Event #2), apparently backsided, developed by the time. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050506. 20:30 WSW - Extremely faint and diffuse front develops in the aftermath of previous complex event. Slow development of a system of loops can be seen superposed in the LOS. 22:06 S - Extremely faint expanding loop front. It fades throughout C3. 23:30 W - Bright spray-like front with faint and diffuse extensions to S. It fades throughout C3. ---------------------------------------------------------------------------------- 07-May-2005: ************ 01:31 WSW - Bright narrow structure and diffuse brightening follows event reported to start at 23:30 UT on previous day. Most likely part of the same event. 03:54 N - Faint and wide expanding loop front. It fades throughout C3. 08:30 W - Apparently two events partly superposed in the LOS: i) Very bright ragged loop front developing toward W. ii) A faint and diffuse front just appearing a little bit to S. By 09:06 UT, the first front already reached the C2 FOV, while the second one becomes clearer (and brighter) developing toward WSW. By 09:30 UT, bright material follows this second front (bright inner core). GOES recorded an M 1.4 X-ray flare on NOAA AR 10756 (S05W89) between 07:57 - 08:19 UT with peak emission at 08:13 UT. A B9.1 X-ray flare follows (S06W80) between 09:07 - 09:26 UT with peak emission at 09:16 UT. 14:06 NE - Couple of extremely faint expanding fronts. Barely visible in C3. 20:06 SW Extremely faint blob-like front. ---------------------------------------------------------------------------------- 08-May-2005: ************ 06:06 S - Very faint and ragged elongated loop front. It is followed by a similar one at around 12:06 UT. They both fade throughout C3. 06:30 SW - Diffuse front superposed in the LOS with existing twisted structures. By 07:54 UT, a faint expanding loop front develops. 09:54 E - Faint fan-like front. It fades throughout C2. 15:54 W - Bright and ragged loop front. Excess brightness can already be seen by 15:30 UT. Extremely faint loop-like extensions to N. 17:06 SE - Ragged and very elongated loop front. It fades throughout C3. 20:06 WNW - Spray-like front. It fades throughout C3. ---------------------------------------------------------------------------------- 09-May-2005: ************ 01:31 WNW - Elongated and bright loop front. It fades throughout C3. 02:30 WNW - Bright and ragged loop front. Much brighter than the previous one. It fades throughout C3. 05:30 WNW - Faint and ragged (elongated) loop front. It fades throughout C3. Another one at 07:32 UT, which quickly fades. 09:54 WNW - Ragged loop front. It fades throughout C3. 13:31 WNW - Another ragged loop front that also fades throughout C3. 13:31 E - Diffuse brightening precedes big and bright expanding loop front with apparently twisted inner core. 13:31 SSW - Jet-like front that quickly fades. ---------------------------------------------------------------------------------- 10-May-2005: ************ 00:54 E - Thin and very elongated loop front at the PA of the trail part of event reported to start at 13:31 UT on previous day. 01:31 SW - Jet-like front. 02:30 SE - Jet-like front. 03:54 W - Elongated and diffuse loop front. It fades throughout C3. 06:06 SW - Ragged and diffuse loop front. Faint extension above SSW and the S Pole. GOES reported an M1.3 X-ray flare from NOAA AR 10758 (S10W30) between 05:03 - 05:36 UT with peak emission at 05:23 UT. 08:06 W - Thin spray-like front with apparently twisted trailing material developing slightly toward WNW. 08:30 NNW - Long jet-like front. 14:30 W - Diffuse and elongated loop front followed by another one a little bit to N. They both quickly fade. 16:06 W - Diffuse asymmetric and ragged loop front. Another front on SW by 16:54 UT. Extremely faint and diffuse extensions surround the C2 occulting disk by 17:30 UT. The extensions are so faint that apparently they are not visible on C3. 19:31 WNW - Bright ragged front(s) and trailing material. 20:58 E - Bright ragged front with extremely faint extensions to N. GOES reported a C5.8 X-ray flare from NOAA AR 10759 (N10E47) between 19:38 - 20:05 UT with peak emission at 19:58 UT. ---------------------------------------------------------------------------------- 11-May-2005: ************ 01:31 WNW - Bright ragged front in the trailing material of event reported to start at 19:31 UT on previous day. 04:30 SW - Very faint and diffuse loop front. It fades close to the inner edge of C3. 07:31 SW - Big ragged loop front. By 08:30 UT a not-well-defined front develops a little bit to N, on WNW. Some expanding loop fronts can be seen in the trailing material afterward. GOES reported an M1.2 X-ray flare from NOAA AR 10758 (S11W45) between 06:11 - 06:56 UT with peak emission at 06:41 UT. The event fade throughout C3. **** EIT Shutterless Campign, Segment #2 between 17:00 - 19:30 UT **** **** No LASCO images during that time. **** 20:13 SW - Bright ragged loop front that later develops as a Full Halo CME. (HALO) Note that already in previous frame, i.e. at 19:42 UT, a very small brightening can already be discerned. Diffuse extensions surround completely the C2 occulting disk by 21:05 UT. The event was first seen in C3 at 20:40 UT appearing above the SW Limb. The diffuse (almost) circular extensions are first seen in next frame, at 21:34 UT. By 22:22 UT the C3 occulting disk is well covered. The mean plane-of-sky speed of the LE of the event (based on C3 data) at PA 231 was ~ 470 km/sec, showing an slight deceleration. GOES reported an M1.1 X-ray flare on NOAA AR 10758 (S11W51) between 19:22 - 19:55 UT with peak emission at 19:38 UT. EIT was in Segment #2 of a Shutterless Campaign, between 17:00 - 19:30 UT, and therefore only subframes (in 195 A) were taken during that time with a cadence of about 1 image per minute. Fortunately, the subframes were centered on AR 10758. Running difference of these images show a strong brightening starting at around 19:21 UT. By 19:24 UT, a ragged structure starts to lift off toward SW. EIT 195 CME watch images resumed at 19:51 UT. An intensity disturbance traveling mainly toward S and SE of the AR is seen by the time. In summary, the event has therefore been determined as a Full Halo CME, frontsided, associated with an M- class X-ray flare on NOAA AR 10758. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050511. ---------------------------------------------------------------------------------- 12-May-2005: ************ 03:52 E - Jet-like front. 04:52 WNW - Diffuse and ragged front that fades throughout C2. **** No LASCO C2 Data between 06:22 - 11:22 UT **** **** due to IPS "C3 only" timeframe. **** 14:22 SW - Diffuse loop front that fades throughout C2. 17:52 NNW - Expanding diffuse loop front. It fades throughout C3. 21:52 N - Jet-like front developing slightly toward NNW. 23:22 E - Wide and diffuse fan-like front that fades close to the inner edge of C3. 23:22 NNW - Diffuse loop front developing like pushed toward S. ---------------------------------------------------------------------------------- 13-May-2005: ************ **** No LASCO C2 Data between 04:52 - 09:52 UT **** **** due to IPS "C3 only" timeframe. **** 17:22 HALO - Nice and bright full halo event. The event was first seen in C2 at 17:22 UT already half way to the end of the C2 FOV and completely surrounding the C2 occulting. The event looks brighter all above the NE Limb. Unfortunately, the LASCO Electronic Box (LEB) failed afterward, and therefore there are no more C2 images until 23:22 UT. For the same reason, there is a C3 data gap between 17:50 and 22:50 UT, and an EIT 195 data gap between 17:37 and 22:57 UT. The event was first seen in C3 at 17:42 UT already as a very symmetric and bright halo. Next C3 frame available was taken at 23:12 UT. By that time, the halo event is no longer visible in the C3 FOV. A rough estimation of the mean plane-of- sky speed (rough because it was determined with the only 2 frames where the halo was seen) is as follows (LE defined as the position where the intensity gradient is maximum): . PA 000: ~ 794 km/sec . PA 090: ~ 1020 km/sec . PA 180: ~ 927 km/sec . PA 270: ~ 915 km/sec A diffuse front can be seen over the North and South Poles ahead of the main structure of the event. If the LE is considered as the outermost part of this diffuse front, the mean plane-of sky speed is: . PA 000: 1645 km/sec . PA 180: 1640 km/sec GOES reported a long duration M8.0 X-ray flare on NOAA AR 10759 (N12E11) between 16:13 - 17:28 UT with peak emission at 16:57 UT. Associated proton event. The >10 MeV proton flux exceeded the event threshold around 06:00 UT this morning. EIT 195 images show a strong brightening that starts to develop by 16:37 UT. A dimming region develops to SW and NE of the AR. Also a an important and symmetric EIT wave with epicenter on the AR develops. In summary, the event has therefore been determined as a fast and strong Full Halo CME, frontsided, associated with a LDE M-class X-ray event on NOAA AR 10759. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050513. **** No LASCO/EIT Data between 17:50 - 22:50 UT (C2 times) **** **** due to LEB (LASCO Electronic Box) crash. **** ---------------------------------------------------------------------------------- 14-May-2005: ************ **** No LASCO C2 Data between 04:52 - 09:52 UT **** **** due to IPS "C3 only" timeframe. **** 10:22 NW - Faint elongated and expanding loop front already under development after data gap. Another one coming behind. They both fade throughout C3. 10:52 NE - Faint and elongated expanding loop front. It fades throughout C3. 17:52 NE - Spray-like front following event at 10:52 UT. 18:22 NW - Diffuse fan-like front following event at 10:22 UT. It is difficult to say whether this event is an independent event or part of the event reported in previous entry. 20:56 WSW - Bright and big ragged loop front with apparently twisted interior. Faint extensions to N. Early on next day, C2 images show an increase of the proton storm (>10 MeV) under development since the LDE M-class X-ray event and halo on 2005/05/13. By 06:06 UT on next day, the proton storm signature in C2 subsides. EIT 195 images show bright ejecta toward SW from nearby AR 10758 by 20:37 UT. The CME extends to SSW by 21:10 UT. GOES reported a C2.8 X-ray flare on NOAA AR 10758 between 20:18 - 22:36 UT with peak emission at 20:58 UT. **** NOTE: NOAA AR 10758 produced other several C-class X ray flares during the day: - C1.1 peaking at 13:26 UT (S10W90) - C4.0 peaking at 15:06 UT (S09W90) - C3.5 peaking at 15:57 UT (S10W90) ---------------------------------------------------------------------------------- 15-May-2005: ************ **** NOTE: NOAA AR 10758 continue producing C class events until dissapearing behind the limb. Last C-class event from 10758 peaking at 09:42 UT 10:26 SW - Ragged front along streamer. By the time, a kind of reconexion event develops a little bit to N. A ragged loop with the front looking like a ragged blob follows by 13:26 UT. Infalling material on W. 21:50 NNW - Slow development of a system of loops. It is difficult to give an exact time of first appearance. 23:26 S - Extremely faint and diffuse wide loop front. It fades throughout C2. GOES reported a M3.5 X-ray flare from NOAA Ar 10763 (S16E15) between 22:27 - 22:42 UT with peak emission at 22:36 UT. EIT 195 shows a wave, and a dimming region to S, WNW, and W of the AR. A C2.1 X-ray flare follows from the same Ar (S16E20) between 23:46 - 00:29 (+1) UT with peak emission at 00:03 UT (on May 16). **** NOTE: Please note that 10763 produced another four C-class X-ray flares earlier in the day (if any signature of C2 events associated to them, too faint to be discernible). ---------------------------------------------------------------------------------- 16-May-2005: ************ 03:26 S - Another extremely faint (barely discernible) and diffuse loop front. Brightening on SE that could be part of. Nothing can be discerned in C3. GOES reported an M1.4 X-ray flare from NOAA AR 10763 (S16E18) between 02:33 - 02:50 UT with peak emission at 02:43 UT. EIT 195 shows a loop brightening at the center of the AR by 02:48 UT. Loops to S of the AR disappear. 06:06 E - Extremely faint slowly-expanding system of loops spanning all above the north eastern limb, up to the N Pole. Also too faint in C3, fading close to its inner edge. 10:50 E - Faint and diffuse fan-like front. It fades throughout C2. 13:50 NW - Bright front above the NW limb. By 14:26 UT, a wide and diffuse Partial loop front starts to be visible on NNW, partly superposed in the Halo LOS with the former bright front. The whole event (hereafter Event #1) expands as it develops. Note that by 14:50 UT, a bright front starts to be seen on WSW (hereafter Event #2). The development of Event #2 seems to be affected by the expansion of Event #1. Infalling material can be seen afterward on WSW. The Event #1 (in fact, the event which could have been potentially geoeffective) was first seen in C3 at 15:18 UT above the NW Limb. The diffuse front on NNW mentioned at the beginning makes its appearance at 15:42 UT on NNW. The mean plane-of-sky speed of the LE of Event #1 at PA 311 was ~ 390 km/sec (based on C3 data). The event spans in C3, at 21:18 UT, ~ 120 deg (form PA 280 - 040), though it is difficult to give an accurate value due to its faintness. GOES reported a C1.2 X-ray flare from NOAA AR 10759 (N15W27) between 12:46 - 13:12 UT with peak emission at 13:01 UT. EIT 195 images show the ejection of material toward NE of the AR by 12:36 UT. An intensity disturbance traveling away from the AR toward NE, N, and NW can be seen afterward (all signatures most likely related to Event #1). By 13:48 UT, the open up of a system of loops on WSW (barely backsided) starts to develop (EIT counterpart of Event #2). In summary, the event (Event#1) has therefore been determined as a partial halo CME, frontsided, associated with a C-class X-ray flare on NOAA AR 10759. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050516. 14:50 WSW - Initially bright ragged front. Development seems to be affected by the expansion of event at 13:50 UT. Infalling material (see Event at 13:50 UT). 20:50 NNW - Faint expanding loop front. It fades throughout C3. **** NOTE: During the day NOAA AR 10763 produced 2 M-class X-ray flares (an M1.4 at S16E18 peaking at 02:43 UT, and a M1.6 at S16E14 peaking at 09:08 UT). As for the first one (reported above), only an extremely faint (barely discernible) and diffuse loop front above the S Pole and brightening on SE (at 03:06 UT ) could be observed. Nothing can be discerned on C3. EIT 195 shows a loop brightening at the center of AR 10763 by 02:48 UT. Loops to S of the AR disappear. As for the second one, there is practically no signatures discernible in the LASCO coronagraphs. ---------------------------------------------------------------------------------- 17-May-2005: ************ 03:06 WSW - Initially bright ragged front. The event fades close to the inner edge of C3. EIT 195 images show ejection of material on the WSW Limb from barely behind the disk between 02:24 - 03:36 UT. 04:06 NW - Diffuse jet-like front. 03:50 HALO - Extremely faint and diffuse brightening all around the occulting disk (though not very clear at this time). Please note that since 03:06 UT an (initially) bright ragged front was seen above the WSW Limb, fading out then close to the inner edge of C3. This particular feature corresponds to ejection of material seen by EIT 195 on the WSW Limb from barely behind the disk between 02:24 - 03:36 UT and should not be confused with the main event. Coming back to the halo event... the event in itself is so faint that is barely discernible in C3, where one can say that it is first discerned at around 08:18 UT. A very rough estimation of the mean plane-of-sky speed of the LE of the event based on C2 data (where at least it is possible to measure something) is ~ 300 km/sec (at PA 211). GOES reported an M1.8 X-ray flare from NOAA AR 10763 (S15W00) between 02:31 - 02:52 UT with peak emission at 02:39 UT. EIT 195 images show a strong brightening at 02:36 UT on the aforementioned AR. A clear wave is seen then developing toward N, W, S, and SE of the AR between 02:48 and 03:36 UT. Also a dimming region to N and S of the AR. The AR continued flaring afterward (at the time of writing: a C8.4 peaking at 04:03 UT, and a C2.8 peaking at 05:53 UT). In summary, the event has therefore been determined as a very faint Full Halo CME, frontsided, associated with an M-class X-ray flare on NOAA AR 10763. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050517. 07:27 ESE - Small loop front along streamer. It fades throughout C2. 12:26 W - Diffuse and very asymmetric loop front that fades close to the inner edge of C3. It is followed at ~ 15:50 UT by a very faint ragged front on WNW that fades throughout C3. Gusty outflow. 21:26 ESE - Diffuse and very faint loop front. It fades throughout C2. ---------------------------------------------------------------------------------- 18-May-2005: ************ 00:26 SE - Very faint and diffuse expanding loop front. It fades throughout C3. 02:06 SW - Bright and ragged loop front. Infalling features in the trailing material on WSW (tadpole-like). EIT 195 images show a signatures of a big backsided CME above the SW Limb, starting at around 01:36 UT. Gusty outflow well into next day on western hemisphere, especially on WNW. 09:06 E - Elongated and very faint feature that fades throughout C2. 21:50 WSW - Faint inverted "V-shaped" feature. It fades throughout C3. 22:26 ENE - Diffuse and faint loop front that fades throughout C2. 22:26 NW - Diffuse and faint jet-like front that quickly fades. ---------------------------------------------------------------------------------- 19-May-2005: ************ 04:50 W - Faint and diffuse front in the gusty outflow that quickly fades. 14:50 W - Elongated front developing slightly toward WNW. It fades throughout C3. 20:50 N - Diffuse jet-like front that quickly fades, followed by an extremely faint loop front (barely discernible). 22:06 W - Initially bright and small front develops as a very elongated feature. Some infalling material. It fades throughout C3. ---------------------------------------------------------------------------------- 20-May-2005: ************ 01:27 S - Elongated jet-like front. 02:26 ESE - Small brightening along streamer that fades throughout C2. 03:26 NNW - Faint and diffuse jet-like front that quickly fades. 03:26 S - Diffuse jet-like front. 06:50 SSE - Wide and very faint expanding loop front. Difficult to give an exact time of first appearance. It fades throughout C3. 19:27 NE - Very slow development of a faint and diffuse front. Difficult to precise the time of first appearance. An apparently twisted (expanding) big structure can be discerned in its interior starting at around 02:00 UT on next day. 22:26 W - Initially bright loop front with some trailing material. It fades throughout C3. ---------------------------------------------------------------------------------- 21-May-2005: ************ 06:26 SW - Couple of faint and relatively wide ragged fronts, one developing mainly toward S (expanding loop), and the other toward WSW (brighter than the other one). They both fade throughout C3. 10:50 S - Very faint expanding loop front. It fades throughout C3. **** EIT 304 CME watch between 07:30 - 12:48 UT **** **** (no EIT 195 images during this time) **** 13:27 SW - Small brightening preceding at 14:06 UT a wide and diffuse expanding loop front. Two apparently different fronts develop behind and seem to push the leading front. The mean plane-of-sky speed of the leading front measured at PA 236 was 285 km/sec, showing practically no acceleration. The event spans almost 120 deg by 20:18 UT (C3 time). No visible signatures on EIT 304 images nor EIT 195 that could be associated to the LASCO event. GOES reported no X-ray events during the day. 20:06 SSW - Faint and diffuse loop front in the aftermath of previous event. ---------------------------------------------------------------------------------- 22-May-2005: ************ 20:26 ENE - Kind of 'reconexion event' at PA ~ 71. Another one follows at around 22:06 UT. The outgoing counterparts of both events fade throughout C3. ---------------------------------------------------------------------------------- 23-May-2005: ************ 10:50 NW - Extremely faint and diffuse loop front. It fades throughout C2. EIT 195 images show signatures of a CME developing with projection toward NW coming out from nearby NOAA AR 10765 (NE quadrant) between 08:36 - 10:36 UT. 12:50 WSW - Faint jet-like front that quickly fades. 17:06 WSW - Very faint and diffuse small front that fades throughout C2. ---------------------------------------------------------------------------------- 24-May-2005: ************ ESE - Several small, faint, and very diffuse ragged fronts along the streamer since late on previous day. They all fade quickly in the C2 FOV. The most relevant ones shown below (05:26 and 08:50). 05:26 ESE - Diffuse front along stremer that fades throughout C2. 08:50 ESE - Diffuse brightening preceding the slow development of a system of faint expanding loops. The development continues all along the day. By the beginning of next day, the expansion seems to become more pronounced. EIT 195 images show a slow event from behind the SE Limb between 04:12 - 09:24 UT, with continued outflow along streamer lines. 14:06 NW - Very diffuse and ragged faint loop front. It fades throughout C2. It is followed at ~ 19:27 UT by another diffuse (though smaller) front. ---------------------------------------------------------------------------------- 25-May-2005: ************ 03:50 ESE - Curved feature starts to rise very slowly. By late in the afternoon it shows up as what seems to be an elongated loop-like structure with apparently twisted interior. 06:50 N - Jet-like front developing toward NNW. 14:26 NE - Diffuse jet-like front. 20:00 WSW - Very faint ragged loop front. Difficult to give an exact time of first appearance. It fades throughout C3. Note that an extremely faint and diffuse asymetric loop front can be guessed preceding the faint ragged loop front, spanning to lmost the S Pole. It is too faint to be discerned in C3. ---------------------------------------------------------------------------------- 26-May-2005: ************ NW - Very slow development of a system of faint loops that started to be seen by the end of previous day. Some small and faint blob- like fronts superposed in the LOS (moving faster). **** EIT 304 CME watch between 13:34 - 24:00 UT **** **** (no EIT 195 images during this time) **** 13:27 SW - Diffuse loop front that initially shows up as a fan-like front. 15:06 SW - LASCO/EIT observed a full halo event. The event was first clearly (HALO) seen in C2 at 15:06 UT all above the SW Limb and S Pole. However, a thin brightening just above southern edge of the occulting disk can already be guessed in previous frame (i.e., at 14:50 UT). The event develops in the C2 FOV as a bright, wide, and expanding loop front. It superposes in the LOS with the trailing part of a prior (relative narrow) event developing on SW (which first appeared in C2 by 13:27 UT). During its evolution in C2, very faint circular extensions can be discerned covering the occulting disk. Our main event is first seen in C3 just appearing above the SW Limb at 15:42 UT. By 16:18 UT, faint and diffuse circular extensions surround the occulting disk. The plane-of-sky projection of the bulk of the CME develops toward SW. The mean plane-of-sky speed of the event at PA 235 was ~ 575 km/sec, showing a slight deceleration (based on C2 and C3 data; last C3 frame at 17:18 UT, LE at ~ 9.5 solar radii). GOES reported several B-class X-ray flares on NOAA AR 10767 during the day. In particular, a B7.5 X-ray flare (on ~ S09E15) between 13:10 - 15:08 UT with peak emission at 14:20 UT (LDE) is most likely associated with the event recorded by LASCO. EIT 195 running difference images show by 12:36 UT a very faint signature of an apparently backsided CME above the SW Limb (EIT 195 counterpart of the event first seen in C2 at 13:27 UT, not associated with our main event). The EIT 195 CME watch was interrupted then at 12:48 UT to start the CME watch in 304 A (JOP 124: Eruptive Filament in Active Region). EIT 304 images show the eruption of a backsided prominence already above the SW limb at 13:19 UT (EIT 304 counterpart of C2 event at 13:27 UT). Top of post-event arcades visible by 13:36 UT. By 13:48 UT, signatures of our main event start to be visible. In particular, material ejected toward SW from nearby AR 10767. In addition, more material (1) shows up above the SW Limb (a little bit to S of the barely backsided prominence ejection). Inspection of the 304 movie seems to indicate that the latter (1) could be related to the ejection from nearby AR 10767. In summary, the event has therefore been determined as a Full Halo Event, frontsided, associated with a LDE B-class X-ray flare from AR 10767 and (apparently) filament ejection. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050526. 21:26 E - Initially faint loop front develops as a wide loop front with faint extensions spanning up to the S Pole. By 22:26 UT, a very faint and diffuse front can be discerned on ENE, moving apparently faster than the loop just mentioned above (it looks like extremely faint circular extensions cover the occulting disk, giving the appearance of a very faint full halo event). This front on ENE is followed at 23:26 UT, by a faint and ragged loop front. Also by 23:26 UT starts to be discernible, above the N Pole, a faint and diffuse loop front. It is difficult to establish the association (if any) between the different features observed. They all fade throughout C3. GOES recorded a C8.6 X-ray flare from NOAA AR 10767 (S08E11) between 20:57 - 22:04 UT with peak emission at 21:39 UT. EIT 304 running difference images show a couple of brightenings on AR 10767 (at 21:13 and 21:36 UT). ---------------------------------------------------------------------------------- 27-May-2005: ************ **** EIT 304 CME watch between 00:00 - 24:00 UT **** **** (no EIT 195 images during this time) **** 00:50 SSW - Expanding loop front. Note that by 23:50 UT on previous day a thin brightening can already be guessed. It is followed at 02:26 UT by a narrower front moving apparently faster. The event partly superposes in the LOS with some small ragged fronts and gusty outflow under development on WSW. 06:26 ESE - Ragged loop front followed at 07:26, 08:26, 09:50, 11:26, 17:50, and 21:26 UT by similar (though some narrrower) fronts. 08:06 NW - A ragged front develops behind the faint system of loops under development since early on previous day. 08:50 SW - Asymetric (spray-like) loop front. Difficult to give an exact time of first appearance. It is followed at 10:50 UT by a faint and elongated loop front a little bit to S. By 13:26 UT, a couple of faint 'half loop' fronts expanding toward WSW develops. Some small blob-like fronts by the end of the day. All these features fade throughout C3. 15:26 NW - Very faint and ragged front. Some small ragged blob-like fronts follow during the rest of the day, all of them fading throughout C3. ---------------------------------------------------------------------------------- 28-May-2005: LASCO Extra PBs for 3D CME Study. ************ **** NOTE: **** Between 2005/05/28 - 2005/06/05: LASCO Extra PBs for 3D CME Study. **** During this time (for the CME watch): **** - only 1 C2 Orange/Clear per hour; **** - only 1 C3 Clear/Clear per hour; and **** - No EIT CME Watch (only synoptic plan: 4 EIT 195 images per day). 03:32 ESE - Very faint and elongated loop front that apparently fades before reaching the C3 FOV. 09:32 E - Not-well defined and faint front followed at 13:32 UT by a similar one. Both fronts fade throughout C2. 07:32 WNW - Faint and not-well-defined front. It fades throughout C3. 13:32 WNW - Ragged and elongated blob-like front. Gusty outflow. 15:32 SE - Ragged front. It fades throughout C3. 16:32 E - Ragged loop front coming behind event at 13:32 UT (see entry at 09:32 UT). Difficult to give an exact time of first appearance. ---------------------------------------------------------------------------------- 29-May-2005: LASCO Extra PBs for 3D CME Study (see Note on May 28). ************ 00:32 SE - Ragged front that fades throughout C3. 11:32 NW - Faint and expanding (slow) loop front. Several blob-like fronts to south developing faster. 12:32 E - Elongated brightening (spray-like) preceding at 15:32 UT a bright and ragged loop front. ---------------------------------------------------------------------------------- 30-May-2005: LASCO Extra PBs for 3D CME Study (see Note on May 28). ************ 00:32 E - Another bright loop front (brighter than the one at 15:32 UT on previous day). **** 06:00 - 09:00 UT: C2 Plumes Study **** **** During this time: C2 orange/clear subfield images at a **** **** 5 min cadence (FOV 14x16 LOCS block region over the South Pole). **** **** --> No LASCO CME watch during the time of the run. **** 09:32 W - Big loop front already at the end of the C2 FOV. GOES reported no significant X-ray activity by the time. 13:32 ENE - Diffuse front develops as a wide and expanding ragged loop front. By 16:32 UT, an elongated (and relatively narrow) front follows on ENE. The outer front of the event spans almost 120 deg by 19:32 UT, from a little past the N Pole to around PA 120 deg. All features observed fade throughout C3. 19:32 WNW - Narrow ragged loop front. 20:32 ESE - Ragged loop front just a little bit to N of the southern leg of the wide expanding loop front at 13:32 UT. It moves apparently faster than the features described in entry at 13:32 UT. This front on ESE is preceded by a faint and diffuse front. It fades throughout C3. ---------------------------------------------------------------------------------- 31-May-2005: LASCO Extra PBs for 3D CME Study (see Note on May 28). ************ 04:32 W - Slow development of a faint system of loops. **** 06:00 - 09:00 UT: C2 Plumes Study **** **** During this time: C2 orange/clear subfield images at a **** **** 5 min cadence (FOV 14x16 LOCS block region over the South Pole). **** **** --> No LASCO CME watch during the time of the run. **** 11:32 NE - Thin and elongated diffuse loop front. It apparently fades throughout C2. 15:32 NNW - Bright and wide loop front. GOES reported a C2.4 X-ray flare on NOAA AR 10770 (N13W23) between 14:33 - 14:57 UT with peak emission at 14:42 UT. 19:32 E - Ragged (not-well-defined) front. ================================================================================== 01-Jun-2005: LASCO Extra PBs for 3D CME Study (see Note on May 28). ************ W - The slow development of a system of faint loops continues. 03:32 ESE - Big and bright loop front, with bright interior. GOES reported an impulsive M1.7 X-ray flare on NOAA AR 10772 (S18E49) between 02:36 - 02:46 UT with peak emission at 02:43 UT. A C1.2 X-ray flare on the same AR follows (S18E48), between 04:34 - 04:47 UT with peak emission at 04:42 UT. **** 06:00 - 09:00 UT: C2 Plumes Study **** **** During this time: C2 orange/clear subfield images at a **** **** 5 min cadence (FOV 14x16 LOCS block region over the South Pole). **** **** --> No LASCO CME watch during the time of the run. **** 09:32 E - Apparently another CME followed the one reported at 03:32 UT: Ragged front under development after data gap. GOES recorded a C2.0 X-ray flare form NOAA AR 10772 (S18E47) between 06:57 - 07:09 UT with peak emission at 07:04 UT. 11:32 E - Bright and ragged loop front in the trailing material of previous event. GOES reported an impulsive C2.3 X-ray flare on NOAA AR 10772 (S17E45) between 10:41 - 10:57 UT with peak emission at 10:51 UT followed by a couple of C1.0 X-ray flares from the same AR peaking at 11:49 and 12:46 UT. Please note that also a couple of B-class flares occurred on the same AR peaking at 09:42 and 08:40 UT. 18:32 E - Bright and small front just appearing. By the time of the following frame (20:32 UT) only some apparent (faint) trailing material can be discerned. No clear signatures in C3. GOES recorded the following impulsive X-ray events from NOAA AR 10772 by the time: . a C3.1 X-ray flare (S18E41) between 17:46 - 17:58 UT peaking at 17:55 UT, and . a C5.9 X-ray flare (S16E40) between 18:00 - 18:21 UT peaking at 18:11 UT. ---------------------------------------------------------------------------------- 02-Jun-2005: LASCO Extra PBs for 3D CME Study (see Note on May 28). ************ W - The slow development of a system of faint loops continues. 00:32 E - Bright ragged front already half way to the end of the C2 FOV. GOES recorded a C7.2 X-ray flare late on previous day from NOAA AR 10772 (S17E38), between 22:03 - 22:25 UT with peak emission at 22:18 UT. 02:32 E - Small front just appearing. It develops as a bright ragged front by 03:32 UT. **** 06:00 - 09:00 UT: C2 Plumes Study **** **** During this time: C2 orange/clear subfield images at a **** **** 5 min cadence (FOV 14x16 LOCS block region over the South Pole). **** **** --> No LASCO CME watch during the time of the run. **** 13:32 E - Another bright ragged front. Extremely faint extensions can be guessed to S. GOES reportes a B8.7 X-ray flare on NOAA AR 10772 (S17E31) between 12:01 - 12:23 UT with peak emission at 12:10 UT. 18:32 W - Faint and diffuse loop front superposed in the LOS with the slow development of a system of faint loops. Difficult to give an exact time of first appearance. It was first seen in C3 at 20:38 UT, developing slightly toward WSW. 19:32 ESE - Diffuse and ragged front. It fades relatively close to the inner edge of C3. ---------------------------------------------------------------------------------- 03-Jun-2005: LASCO Extra PBs for 3D CME Study (see Note on May 28). ************ W - The slow development of a system of faint loops continues. 01:32 ESE - Very elongated loop-like front. It fades throughout C3. 04:32 ESE - Diffuse loop-like brightening (some signatures already in previous frame, by 03:32 UT). Inpection of the C2 Orange/-60 deg sequence shows the diffuse front first appearing at 04:09 UT, followed by a brighter ragged loop front at 05:09 UT (though by 04:49 UT some brightening can already be seen). In this sequence, this loop front appears much brighter above the E limb. Signatures of the event are gone after the data gap. GOES reported on NOAA AR 10772 the following events: . a C3.1 X-ray flare (S17E21) between 01:53 - 02:38 UT with peak emission at 02:24 UT, and . an M1.3 X-ray flare (S17E22) between 04:03 - 04:16 UT with peak emission at 04:11 UT. **** 06:00 - 09:00 UT: C2 Plumes Study **** **** During this time: C2 orange/clear subfield images at a **** **** 5 min cadence (FOV 14x16 LOCS block region over the South Pole). **** **** --> No LASCO CME watch during the time of the run. **** 10:49 ENE - (Time of C2 Orange/-60 deg): Faint and diffuse ragged loop front. The front is completely surpassed by a very bright and big loop front by 12:49 UT (time at which this big loop front is first seen, its LE being already at the end of the C2 FOV). See next event for details. 13:32 E - Bright and wide ragged loop front on the E Limb, already past (HALO) the end of the FOV. Extra polarization brightness images (for the 3D CME study under way) were being taken during the time of the event. Therefore, according to the different C2 sets, the time of first appearance is as follows (Filter/Polarizer): . C2 Orange/+60 deg: 12:45 UT . C2 Orange/0 deg: 12:47 UT . C2 Orange/-60 deg: 12:49 UT . C2 Orange/Clear: 13:32 UT Faint extensions above the N and S Pole can be seen by the time, which seem to surround the C2 occulting disk by 15:32 UT -barely above the W Limb- (C2 image at 12:32 UT non-existent). As for C3, the time of first appearance is as follows: . C3 Clear/Clear: 12:38 UT. The faint extensions seem to surround the C3 occulting disk by 13:38 UT. . C3 Orange/-60 deg: 12:54 UT . C3 Orange/+60 deg: 12:56 UT The mean plane-of-sky speed of the LE of the event was ~ 1660 km/sec at PA 72 (as measured on C3 Clear/Clear data, only 3 frames - in the 4th frame the LE is out of the C3 FOV- ). GOES reported high activity on NOAA AR 10772 during the present and past 2 days (including an impulsive M1.3 X-ray flare at S17E22 that peaked on 06/03 at 04:11 UT). However, the most likely X-ray event associated to the event observed by LASCO was apparently not related to that AR but to an M1.0 X-ray flare that occurred on N15E90 between 11:51 - 12:45 UT with peak emission at 12:26 UT. The event has therefore been determined as a very asymmetric (and extremely faint) Full Halo Event, most likely associated with an energetic E limb event (M-class X-ray flare). Please note that it is the associated shock the one which gives the appearance of a full halo to the event and hence the one that could have a component extending toward Earth. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050603. 19:32 ENE - Ragged front in the aftermath of previous event. Gusty outflow into next day. ---------------------------------------------------------------------------------- 04-Jun-2005: LASCO Extra PBs for 3D CME Study (see Note on May 28). ************ NOTE: Multiple C-class X-ray flares on NOAA AR 10722 during the day (peaks at 00:39 -S17E08-, 00:55 -S18E08-, 01:50 -S18E07-, 06:43 -S18E05-, 08:48 -S18E04-, 11:40 -S18E02-, and 16:56 UT -S17W01-). 01:32 S - Ragged front developing slightly toward ESE. Some faint ragged extension by 02:32 UT on SE. It fades throughout C3. Gusty outflow afterward all along the day (rotating toward SSW as it develops). 10:32 ENE - Loop front that fades throughout C2. 14:32 W - Bright ragged loop front. A couple of faint and expanding loop fronts follow by 17:32 and 21:32 UT. They all fade throughout C3. Gusty outflow in the form of faint expanding loop-like fronts well into next day. 20:32 E - Jet-like front. ---------------------------------------------------------------------------------- 05-Jun-2005: Last day of LASCO Extra PBs for 3D CME Study (see Note on May 28). ************ **** Telemetry KEYHOLE: 2005/06/05 - 2005/06/25: 26 m stations **** **** 2005/06/09 - 2005/06/20: 34 m stations **** **** During the KEYHOLE, SOHO will stay in TM Submode 5, and **** **** LASCO will be in synoptic improved program **** **** (12 min cadence C2, 30 min cadence C3), with little loss **** **** of telemetry throughout due to the advanced recorder setup. **** 00:32 ESE - Bright and asymmetric loop front already past the end of the C2 FOV. It fades throughout C3. 01:32 ENE - Faint and diffuse (and slightly asymmetric) loop front. 06:32 E - Bright thin fan-like front (fast) developing slightly toward ENE. It fades close to the inner edge of C3. 12:32 E - Another fast front (little bit bigger that the previous one at 06:32 UT) developing slightly toward ENE. It also fades close to the inner edge of C3. 14:32 ESE - Bright loop front. GOES reported a C3.5 X-ray flare on NOAA AR 10776 (S08E80) between 13:04 - 14:08 UT with peak emission at 13:50 UT. 17:32 SW - Initially bright elongated loop front. Very faint in C3. It fades close to the inner edge. ---------------------------------------------------------------------------------- 06-Jun-2005: KEYHOLE ************ **** 2005/05/06 - 2005/06/24: EIT Bakeout (==> No EIT CME Watch). **** **** EIT performed the long pre-bake calset (06/06 15:58-21:45 UT) **** **** and went to heaters on at 21:52 UT. EIT will be in bake till **** **** June 24 @ 10:00 UT and should resume imaging by (06/24) @ ~ **** **** 20:00 UT. **** 05:06 E - Initially bright and ragged loop front that fades very close to the inner edge of the C3 FOV. Kind of reconexion event occurs in its trailing material. Afterward, by around 08:06 UT, a ragged blob-like front starts to move out (it fades throughout C3). 11:06 E - Very faint ragged loop fronts developing slightly toward ENE. Gusty outflow. 16:26 SSE - Very faint elongated loop front rotating toward SSW as it develops. Extremely faint in C3. ---------------------------------------------------------------------------------- 07-Jun-2005: KEYHOLE ************ 02:00 ENE - Ragged front along streamer. 02:36 E - Diffuse and ragged elongated loop front. 10:24 NE - Diffuse loop front starts to be discernible. It develops as a bright loop front by ~ 11:12 UT, and is followed by nice prominence material at 12:12 UT (the latter is brighter than the loop front). The mean plane-of-sky speed of the LE of the loop front at PA 61 was around 368 km/sec, showing slight acceleration. 14:24 NW - Very faint elongated loop front. It fades throughout C2. ---------------------------------------------------------------------------------- 08-Jun-2005: KEYHOLE ************ 02:00 NE - Very faint elongated front that fades throughout C2. 05:12 W - Extremely faint and diffuse brightening. It develops as an Partial asymmetric and expanding loop front, extending all above the SW Halo limb, up to past the S Pole. The most western part of the LE reaches the end of the C2 FOV by 13:12 UT. By that time, the part of the LE above the S Pole is only midway to the end of the FOV. The event is first seen in C3 at 11:18 UT just appearing above the W Limb. The angular span of the event at 17:42 UT is ~ 190 deg (from PA 130 - 320), and still expanding. The mean plane of-sky speed of the LE at PA 285 was ~ 166 km/sec (based on C2 and C3 data). The HT diagram shows an accelerated profile (speed < 100 km/sec at the beginning of the C2 FOV, almost 300 km/sec at ~ 12 solar radii). There are no EIT images available (EIT CCD bakeout under way: 2005/06/06 21:52 - 2005/06/24 20:00 UT). GOES reported several B- and C-class X-ray flares during the day, all from NOAA AR 10776 (in average at around S06E40). The projection of the event in the plane-of-sky as observed in the LASCO FOVs makes it unlikely a direct association of the event with the X- ray activity reported. On the other hand, images of the GOES Solar X-ray Imager (SXI) show a small and quick brightening to the East of NOAA AR 10772, starting at 01:41 UT and peaking at 01:45 UT. The BBSO H alpha image taken on 2005/06/07 at 23:30 UT shows the existence of a filament to NNW of AR 10772 (centroid of the filament at around S05W52). The corresponding H alpha image taken on 2005/06/08 at 19:00 UT no longer shows that filament (unless projection effects make me misinterpret the image). In summary, the event has therefore been determined as a faint and very slow partial halo CME, apparently associated to the disappearance of a filament to NNW of AR 10772. Should that be the case, then a component of the event toward Earth would be likely. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050608. 11:00 ENE - Faint blob-like front. Some gusty outflow, very faint. ---------------------------------------------------------------------------------- 09-Jun-2005: KEYHOLE ************ 02:00 SW - Extremely faint and diffuse front develops as a faint and diffuse loop front. It fades throughout C2. 04:00 S - Diffuse jet-like front developing slightly toward SSE. 05:12 WNW - Very faint and diffuse front. Difficult to establish its association (if any) with next two following events. It fades throughout C2. 05:12 ESE - Very faint ragged front that fades throughout C2. 06:00 SE - Fainter (than previous event) expanding loop-like front. It also fades throughout C2. 14:24 ENE - Faint expanding loop front [1]. . By that time, a very diffuse front [2] develops above the W Limb. . By 15:48 UT, an expanding ragged front can be seen developing above the N Pole. . By 16:24 UT, another expanding and ragged loop front [3] starts to be discernible above the E Limb. C3 shows: . a diffuse loop front on WSW [2] (first seen at 15:18 UT) that quickly fades, . a diffuse and expanding front on NE [1] (first seen at 15:42 UT), and . another expanding front on NE first seen at 19:42 UT [3] (note that there is a C3 data gap betwen 16:42 - 19:42 UT). GOES reported: . a C1.5 X-ray flare on NOAA AR 10775 (N07E13) between 13:28 - 14:23 UT with peak emission at 13:34 UT, . a C1.0 X-ray flare on NOAA AR 10776 (S07E18) between 16:28 - 16:34 UT with peak emission at 16:31 UT, and . a B8.7 X-ray flare on NOAA AR 10776 (S06E18) between 16:54 - 17:01 UT with peak emission at 16:58 UT. ---------------------------------------------------------------------------------- 10-Jun-2005: KEYHOLE ************ 00:12 NE - Very faint and diffuse front that quickly fades. 05:24 SW - Apparently narrow and twisted structure developing very slowly along the streamer. Difficult to give an exact time of first appearance. Some gusty outflow afterward. 19:24 SW - Ragged blob-like front starts to form, first seen in C3 at ~ 20:18 UT. It develops faster than previous event. ---------------------------------------------------------------------------------- 11-Jun-2005: KEYHOLE ************ 00:12 NW - Extremely faint (barely visible) expanding loop front. 16:12 WSW - Very faint elongated loop front. 22:00 SE - Diffuse and faint small front that quickly fades. ---------------------------------------------------------------------------------- 12-Jun-2005: KEYHOLE ************ 02:36 W - Diffuse loop like front (hereafter Feature #1) appearing above Complex the W Limb. It was followed at 02:48 UT (on WNW) by a bright Event loop front (hereafter Feature #2), and at 03:24 UT (on W) by Frontsided another loop front developing slightly toward WSW (hereafter Feature #3). Very faint extensions seem to develop above both poles by 04:12 UT. Feature #1 makes its appearance in the C3 FOV at 03:18 UT, showing up above the W Limb; Feature #2 starts to be seen above WNW by 03:42 UT; and Feature #3 appears above W by 04:18 UT. Very faint extensions above the poles can be discerned by 06:42 UT, giving the appearance of a faint halo. The mean plane-of-sky speed of the LE of the different features involved is shown below (based on C3 data): . Feature #1 at PA 267: ~616 km/sec . Feature #2 at PA 308: ~510 km/sec . Feature #3 at PA 252: ~516 km/sec . Extensions on N Pole (PA 0): ~ 295 km/sec GOES reported a long duration C3.0 X-ray event on NOAA AR 10775 (N06W24) between 01:50 - 05:00 UT with peak emission at 03:15 UT. Note that a C3.5 X-ray flare was also reported by the time, as happening on NOAA AR 10776 (S06W09) between 02:30 - 02:48 UT with peak emission at 02:36 UT (Information extracted from http:// www.lmsal.com/solarsoft/latest_events). In summary, the event has therefore been determined as a complex frontsided event (faint halo CME with the bulk of the event developing toward W, as projected on the plane-of-sky), associated with C-class X-ray activity on ARs 10775 and 10776. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050612. 16:00 WNW - Faint and diffuse front preceding a bright and ragged (expanding) loop front at 16:24 UT. GOES reported another LDE event on NOAA AR 10775 (N11W13): a C3.0 X-ray flare between 15:07 - 17:59 UT with peak emission at 16:09 UT. 23:12 WNW - Small and diffuse front that quickly fades. ---------------------------------------------------------------------------------- 13-Jun-2005: KEYHOLE ************ 03:24 WNW - Ragged loop front. It fades throughout C3. **** LASCO Data gap between 05:00 - 07:24 UT. **** 13:00 WNW - Bright ragged front followed at 13:24 UT by a similar one, just a little bit to S. Trailing material. 19:00 ESE - Bright loop front with structured interior. The interior part seems to stay behind, infalling material. Very faint expanding extensions on NE and SE. It is first seen in C3 at 20:18 UT. ---------------------------------------------------------------------------------- 14-Jun-2005: KEYHOLE ************ 07:24 W - Bright, wide, and ragged loop front. Faint ragged extensions can (HALO) be seen all above the N Pole, toward NE, and E at around 09:24 UT. Though extremely faint, they can also be guessed above the S Pole. The event was first seen in C3 at 09:18 UT already well above the W Limb. By 09:42 UT, the C3 occulting disk appears completely surrounded by the faint extensions. Gusty outflow then on WNW. Last C3 image available of the event corresponds to 15:42 UT (afterward, non-recoverable data gap between 16:24 - 24:00 UT). The mean plane-of-sky speed of the LE at PA 267 was ~ 560 km/sec (based on a few C3 frames), showing a very slight acceleration. There are no EIT images available (EIT CCD bake out under way: 2005/06/06 21:52 - 2005/06/24 20:00 UT). GOES reported a C4.2 X-ray flare on NOAA AR 10775 (N10W47) between 06:54 - 07:56 UT with peak emission at 07:30 UT. The X-ray event on AR 10775 was preceded by an impulsive B5.4 X-ray flare on NOAA AR 10776 (S08W43), which occurred between 05:10 - 05:22 UT (peak emission at 05:16 UT). SXI-GOES 12 images show a relatively strong brightening of an (inverted) S-shaped feature on AR 10775 coincident with the reported X-ray flare. In summary, the event has therefore been determined as an asymmetric Full Halo CME, frontsided, associated to C-class X-ray activity on NOAA AR 10775. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050614. 09:48 E - Faint and very ragged front. By 13:36 UT, a very thin and elongated feature develops, fading throughout C2. 13:24 WSW - Elongated loop-like front 16:00 WNW - Bright and ragged loop front. GOES reported a C7.4 X-ray flare on NOAA AR 10775 (N11W61) between 15:22 - 16:13 UT with peak emission at 15:48 UT. Due to the following non-recoverable Data Gap, it is uncertain whether there was a partial or full halo event associated to the X-ray event. **** LASCO Data Gap between 16:24 - 24:00 UT. **** ---------------------------------------------------------------------------------- 15-Jun-2005: KEYHOLE ************ 02:00 W - Narrow front. Development missed in the following data gap. **** LASCO Data Gap between 02:12 - 10:24 UT. **** **** LASCO Data Gap between 11:00 - 18:24 UT. **** ---------------------------------------------------------------------------------- 16-Jun-2005: KEYHOLE ************ 08:36 WNW - Bright ragged loop front, structured interior, and some trailing material. GOES reported a long duration C1.7 X-ray flare on NOAA AR 10775 (N07W89) between 07:21 - 09:39 UT with peak emission at 09:05 UT. 12:00 WNW - A diffuse and faint expanding ragged loop front develops in the trailing material of previous event. **** At ~ 16:05 UT, LASCO closes doors in preparation to S/C Maneuvers **** **** on 2005/06/17. No LASCO images until 2005/06/17 @ ~ 18:00 UT. **** **** Last LASCO C2 image before closing doors: 16:00 UT **** **** Last LASCO C3 image before closing doors: 14:42 UT **** ---------------------------------------------------------------------------------- 17-Jun-2005: KEYHOLE - S/C Maneuvers ************ **** ==> Station keeping, Momentum management, and 180 deg Roll. **** **** No LASCO images during the day (doors closed). **** ---------------------------------------------------------------------------------- 18-Jun-2005: KEYHOLE ************ **** First LASCO C2 image after opening doors: 18:17 UT. **** **** First LASCO C3 image after opening doors: 18:21 UT. **** 18:29 E - Trailing material of event already under development, developing slightly toward ENE. 18:48 WSW - Diffuse front preceding and elongated loop-like feature wih apparently twisted trailing material. It fades throughout C3. 20:12 E - Faint and expanding ragged loop front in the trailing material of event reported at 18:29 UT, developing slightly toward ENE. 23:24 E - Ragged front that develops slightly toward ENE, with faint expanding extensions toward S. Continuous outflow well into next day. **** NOTE: **** GOES reported multiple B-class and several C-class X-ray flares from **** NOAA AR 10780 all along the day (in average around S07E60). ---------------------------------------------------------------------------------- 19-Jun-2005: KEYHOLE ************ 00:48 E - Another ragged front that develops slightly toward ENE, with very faint expanding extensions toward S. 02:12 E - Slow development of a faint system of expanding loops, partly superposed in the LOS with the trailing material of the chain of events reported on E. The system develops as a big and expanding twisted structure. 05:24 SW - Very faint asymmetric loop front that fades throughout C2. 12:00 WNW - Bright and ragged loop front preceded at 09:12 UT by a faint and diffuse feature. 12:36 E - Ragged front with very faint expanding loop-like extensions toward S. 20:48 E - Small front that fades close to the inner edge of C3, preceded by a couple of blob-like fronts developing toward ENE. Very faint expanding extensions to S. 22:36 ESE - Very faint loop front that fades throughout C3. ---------------------------------------------------------------------------------- 20-Jun-2005: KEYHOLE ************ 03:36 W - Bright ragged loop front immediately followed at 03:48 UT by another one at roughly the PA of the southern leg of the former loop front. By ~ 05:00 UT, what looks like the inner core of the second loop front starts to be visible, developing as a big and expanding twisted feature. Some gusty outflow afterward. 10:12 E - Extremely faint loop front that fades throughout C3. Some very faint gusty outflow toward ENE all along the day. ---------------------------------------------------------------------------------- 21-Jun-2005: KEYHOLE ************ 05:00 WNW - Very faint and diffuse front. It fades close to the inner edge of C3. 16:36 NW - Extremely faint loop expanding toward N. It fades throughout C2. 22:00 NE - Very faint outflow. Difficult to give an exact time of first appearance. ---------------------------------------------------------------------------------- 22-Jun-2005: KEYHOLE ************ 01:36 WNW - Extremely faint front that quickly fades. 05:36 W - Faint ragged expanding front. It fades throughout C3. 07:00 NE - Extremely faint elongated loop front that fades close to the inner edge of C3. 17:12 W - Very faint ragged loop front, slightly brighter to S. 21:12 SE - Extremely faint system of expanding loops. ---------------------------------------------------------------------------------- 23-Jun-2005: KEYHOLE ************ 02:12 NE - Faint and diffuse jet-like front. 07:36 W - Very thin and elongated (and diffuse) loop front. It fades close to the inner edge of C3. ---------------------------------------------------------------------------------- 24-Jun-2005: KEYHOLE ************ 00:00 NE - Very faint and diffuse jet-like front that quickly fades. **** LASCO data gap between 07:24 - 14:00 UT. **** 19:53 NNW - Elongated jet-like front developing toward NW. 20:54 E - Big and initially bright ragged loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 25-Jun-2005: KEYHOLE ************ 01:01 WNW - Ragged blob-like front. Difficult to give an exact time of first appearance. **** EIT 195 full res CME watch resumed (after bakeout **** **** and calibrations) on 2005/06/25 @ 01:40 UT. **** 06:54 ENE - Loop-front apparently seen almost edge-on preceding Halo event (see next entry). 08:06 S - Very faint and diffuse front all above the S Pole. By 08:30 UT, (HALO) a bright 'folded-like' feature can be seen rising on ENE, and a faint loop-like front developing on W. By 09:06 UT, the C2 occulting disk is completely covered. The halo event was first seen in the C3 FOV at 08:42 UT, above the E - SE limb. The C3 occulting disk is fully covered by 09:42 UT (emission brighter on ENE). The mean plane-of-sky of the LE at several PA is given below (based on C3 data): . PA 024: 357 km/sec . PA 068: 429 km/sec . PA 119: 880 km/sec (LE very diffuse) . PA 159: 604 km/sec . PA 265: 581 km/sec showing in all cases practically no acceleration. GOES reported no significant X-ray activity by the time. However, it did report i) a C1.3, and ii) a B 4.3 X-ray flares on NOAA AR 10780 (around S09W33) with peak emissions at 03:46 UT and 04:04 UT, respectively. EIT 195 images show a relatively strong brightening on AR 10780 peaking at 03:48 UT. By 04:12 UT, some material seems to be ejected toward SW. Also by that time, a faint intensity disturbance can be seen on the south-east quadrant (on a quiet region of the Sun), apparently developing jointly with the event above the AR 10780. On the other hand, running difference images of EIT 195 show a very faint intensity disturbance above the E Limb at around 08:00 UT, extending toward S as it develops. Also, another one above the SW limb by 08:12 UT. Therefore, despite the frontsided activity observed on both AR 10780 and the quiet region on the southeastern quadrant (they seem to occur too early to be associated with the LASCO event), the event seems to be backsided (based on the faint signatures observed by the right time on the EIT running difference images). In summary, the event has therefore been determined as a full halo event, apparently backsided. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050625. 09:54 E - Slow system of loops starts to be seen on E in the aftermath of previous Halo event. It develops as an expanding and twisted structure (towards ENE). Gusty outflow follows. ---------------------------------------------------------------------------------- 26-Jun-2005: ************ 07:31 NE - Bright loop-like front just appearing. It develops as a slightly (HALO) asymmetric expanding loop front toward N (brighter on NE). By 08:06 UT, very faint extensions all above the S Pole make the event to look like a full halo event. The event was first seen in the C3 FOV at 08:18 UT, just appearing above the NE limb. The 'bulk' of the CME develops toward N, spanning all the way from the E limb, N Pole, up to the W Limb. By 09:42 UT, very faint extensions can be seen above the S Pole. The mean plane-of-sky of the LE at several PA is given below (based on C3 data): . PA 008: 475 km/sec . PA 048: 450 km/sec . PA 274: 444 km/sec showing in all cases a very slight deceleration. EIT 195 running difference images show signatures of a backsided CME starting at 07:36 UT above the E Limb. An intensity disturbance traveling toward N all above the NE limb can be seen afterward. GOES reported a B5.0 X-ray flare on N15E83 between 07:06 - 07:59 UT with peak emission at 07:36 UT, apparently associated with the signatures observed in EIT. In summary, and based on the appearance of the event in EIT running difference images (jointly with the lack of activity on the disk) the event has therefore been determined as an asymmetric full halo event, most likely backsided. Outflow follows on ENE. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050626. 14:30 E - Bright and narrow front. By 14:54 UT, a very faint expanding front with the southern leg at roughly the PA of this narrow front develops toward N. ---------------------------------------------------------------------------------- 27-Jun-2005: ************ **** NOTE: **** Multiple B-class X-ray flares and one C2.8 X-ray flare during the day from **** a region on E (at about N14E84 in average) numbered by the end of the day **** as 10781. 05:06 ENE - Diffuse brightening just appearing. It develops as a bright and ragged loop front with twisted interior. By 08:06 UT, a small and bright feature can be seen developing toward E (at roughly the PA Of the southern leg of the former loop). 12:30 N - Very slow development of an expanding loop front (slightly toward NNW). By ~ 19:31 UT, the development of this front seems to speed up, apparently pushed from behind by an expanding system of loops, which continues into next day. They all fade throughout C3. ---------------------------------------------------------------------------------- 28-Jun-2005: ************ 07:31 ESE - Elongated loop front. It fades throughout C2. 17:06 E - Big and bright loop front. Faint extensions to N. They surround the C2 occulting disk by 18:54 UT. Much gusty outflow on ENE well into next couple days. Some ragged loop fronts can be distinguished in the gusty outflow, as for example at 20:06, 22:06, 01:31, 02:30, and 07:31 UT (the last three on 06/29). EIT 195 images show a big backsided CME already above the E Limb (as a trans-equatorial arcade) by 16:48 UT. ---------------------------------------------------------------------------------- 29-Jun-2005: ************ 00:06 WNW - Diffuse brightening (already seen since late on previous day) preceding the slow development of an expanding and twisted structure. 15:30 SE - Extremely faint and diffuse loop front that quickly fade. 17:54 N - Very faint and diffuse jet-like front toward NNW. 22:30 WNW - Couple of small blob-like fronts. They fade trhoughout C3. 23:30 NE - Faint and elongated loop front that quickly fades. ---------------------------------------------------------------------------------- 30-Jun-2005: ************ 02:30 N - Very faint and diffuse jet-like front that quickly fades. 03:30 W - Blob-like front developing slightly toward WNW. 09:54 N - Faint and diffuse narrow loop-like front that quickly fades. 15:30 E - Bright and elongated ragged loop front developing slightly toward ENE. Gusty outflow then continues. 15:30 S - Very faint expanding loop front developing slightly toward SSE. It fades throughout C3. ================================================================================== 01-Jul-2005: ************ 05:30 ENE - Bright ragged front. Gusty outflow continues. GOES reported a C5.3 X-ray flare on N14E82 between 04:57 - 05:07 UT with peak emission at 05:02 UT. 21:30 ENE - Ragged and asymmetric loop front followed by an expanding loop front very early on next day (difficult to give an exact time of first appearance). Gusty outflow continues well into next day. 22:30 S - Very faint blob-like front that fades throughout C3. ---------------------------------------------------------------------------------- 02-Jul-2005: ************ 04:30 SW - Very faint ragged blob-like front starts to be discernible. A couple more later, a little bit to N. Some infalling material by midday. 14:54 SW - Slow development of a system of faint loops after a small blob- like front. ---------------------------------------------------------------------------------- 03-Jul-2005: ************ 03:30 NNW - Very faint front 'shifting' toward NW-WNW as it develops. Difficult to give an exact time if first appearance. It is not discernible in C3. 11:30 ENE - Diffuse front that quickly fades. Gusty outflow continues. Some reconexion events (with corresponding infalling material) during the day. In particular, one at ~ 17:54 UT at PA ~ 66 deg ("pair formation"). Afterward, ejection of a ragged blob-like front (at ~ 22:06 UT) starting at about 3.15 solar radii. 20:30 WNW - Diffuse front develops as pseudo-continuous outflow. By ~ 23:06 UT, the slow development of a system of faint expanding loop fronts starts to be discerned, superposed in the LOS with the pseudo-continuous outflow. By the middle of next day, the event (i.e., the system of loops) shows up as a big twisted structure. 20:58 E - Jet-like front. 22:06 E - Another jet-like front. ---------------------------------------------------------------------------------- 04-Jul-2005: ************ 00:54 E - Another jet-like front. 05:54 NNE - Jet-like front developing toward NE. 06:30 WSW - Slow development of a system of faint and expanding loop fronts. Difficult to give an exact time of first appearance. Gusty outflow superposed in the LOS. 13:31 N - Very narrow fan-like front that quickly fades. 19:54 ENE - Slow development of a system of faint loops. A relatively bright twisted structure follows late in the day (at ~ 21:30 UT). ---------------------------------------------------------------------------------- 05-Jul-2005: ************ 03:30 WSW - Faint, diffuse, and wide expanding loop front superposed in the LOS with the twisted trail of event reported to start at 06:30 UT on previous day. It is followed by a similar one at 04:06 UT, which apparently merges then with a next one that starts to be seen at ~ 04:54 UT. This whole event surpasses, while in the C3 FOV, the event reported to start at 06:30 UT on previous day. 05:06 NW Blob-like front. It fades throughout C3. 15:30 SE - Bright loop-like front with apparently extremely faint extensions Asymmetric above the S Pole. By 15:54 UT, an apparent distinct front can be Halo discerned behind, developing mainly toward E. By this time on, the faint extensions mentioned above extend up to the W Limb, becoming brighter there. There is a small C2 data gap after 16:30 UT, the next C2 image available corresponding to 18:06 UT. At that time, very faint extensions can already be seen above the N Pole. The event was first seen in the C3 FOV at 16:18 UT, above the SE limb, with very faint extensions developing above the S Pole. A second front is clearly visible above the E Limb by 17:42 UT. By 19:42 UT, the C3 occulting disk appears completely covered. The mean plane-of-sky of the LE of the two main features mentioned above is given below (based on C3 data): i) Outermost front at PA 125: 794 km/sec; ii) Second front at PA 085: 654 km/sec. GOES reported a C1.3 X-ray flare on NOAA AR 10788 (S10E33) between 14:52 - 15:49 UT with peak emission at 15:26 UT. EIT 195 running difference images show a relatively strong brightening on AR 10788 at 15:24 UT, which was preceded by signatures of a CME developing toward SW since 15:00 UT. EIT 195 images show, i) the eruption of a small filament atop the AR starting at ~ 14:24 UT, and ii) the dimming of a region to S-SW of the AR starting at 15:00 UT. In summary, the event has therefore been determined as a faint and asymmetric full halo event, frontsided, associated to a filament eruption and C-class X-ray activity on NOAA AR 10788. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050705. 21:12 W - Diffuse front that quickly vanishes precedes the slow development of a faint and asymmetric loop front early on next day. ---------------------------------------------------------------------------------- 06-Jul-2005: ************ 00:30 E - Small blob-like feature precedes a bright and ragged loop front. It fades throughout C3. Gusty outflow on ENE. 00:30 W - Slow development of a faint and asymmetric loop front. It fades throughout C3. 11:30 WSW - Very faint front. Difficult to give an exact time of first appearance. It fades thorughout C3. 21:26 N - Very faint and diffuse wide front. It develops as a system of Partial wide and expanding loop fronts, the subsequent expanding fronts Halo mainly appearing above the NNE limb until around 05:26 UT on 07/07. The event is first seen in C3 at 01:42 UT (on 07/07) above the NNE limb. By 09:42 UT, the whole event spans in C3 ~ 200 deg (from PA 275 - 115, though the limit on W is not well defined). The mean plane-of-sky speed of the LE at PA 028 was ~ 275 km/sec (based on C3 data). GOES reported multiple C-class (impulsive) X-ray activity on NOAA AR 10786 all along 07/06. In particular, after 17:00 UT we have: - a C5.9 (N09E14) peaking at 17:49 UT, - a C1.4 (N10E14) peaking at 18:46 UT, - a C1.0 (N10E12) peaking at 20:22 UT, and - a C1.0 (N09E12) peaking at 21:24 UT. EIT 195 images show a relatively strong brightening on AR 10786 at 17:48 UT, and some minor brightenings later that roughly match the time of the X-ray spikes. Some time after the brightening at 17:48 UT (i.e., starting at ~ 19:48 UT), a slight dimming region can be seen developing rather far to the ESE of AR 10786. In summary, the event has therefore been determined as a Partial Halo Event. However, despite the frontsided activity observed, I don't find it conclusive to catalog the LASCO event as frontsided. Therefore, there exist the possibility that the event may have been backsided. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050706. ---------------------------------------------------------------------------------- 07-Jul-2005: ************ 04:06 ENE - Slow development of a system of loops along streamer. The event superposes in the LOS with the Partial Halo under development reported to start at 21:26 UT on previous day. **** NOTE: **** LASCO/EIT observed two frontsided events on 2005/07/07, which were **** likely associated with: i) the eruption of a filament south of NOAA **** AR 10786, starting at 11:00 UT (EIT 195 time), hereafter Event "A", **** and ii) an M4.9 X-ray flare on NOAA AR 10786 (N09E03) that peaked at **** 16:29 UT (hereafter Event "B"). Description follows: 12:06 SE - Likely signatures of event "A" were first seen in C2 at 12:06 UT Partial above the SE limb, as a very faint and diffuse front [1]. Note Halo that by 12:26 UT, a slightly brighter front (also diffuse) appears above the E Limb. This particular front could be be associated with activity on NOAA AR 10789 at N17E48 (see below). Finally, by 13:26 UT, a wide loop-like expanding front [2] makes its appearance above the SE limb preceded by a small front (around 12:50 UT) on E. The event seems to barely surround the C2 occulting disk by just 16:06 UT, just before the appearance of the event associated with the M4.9 X-ray flare. The diffuse front [1] is first seen in C3 at 12:42 UT above the ESE Limb, preceding the expanding loop front [2] at 14:42 UT on SE. It is difficult to say whether the event in C3 covers the C3 occulting disk, partly due to the appearance in the C3 FOV at 17:42 UT of the brighter and apparently faster event associated with the M4.9 X-ray flare. The mean plane-of-sky of the LE of [1] was 657 km/sec at PA 108 (big uncertainty in its determination as the LE is too diffuse). As for the front [2], its mean-plane-of-sky speed was 456 km/sec at PA 132. Both cases based on C3 data. GOES reported the following X-ray events by the time: - a C2.6 X-ray flare on NOAA AR 10789 (N17E48) between 12:18 - 12:55 UT with peak emission at 12:29 UT, and - a C3.8 X-ray flare on NOAA AR 10786 (N10E04) between 13:25 - 13:34 UT with peak emission at 13:29 UT. EIT 195 images show the eruption of a filament just a little bit south of AR 10786, starting at ~ 11:00 UT. Corresponding running difference images show the ejection of material toward SE. In summary, the event has been determined as at least a partial halo CME (maybe a very asymmetric full halo event) most likely associated with the eruption of a filament practically at the center of the disk. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050707. 17:06 E - Event "B": The event was first seen in C2 at 17:06 UT all above Asymmetric the E limb, as a wide and ragged front (emission brighter on ENE Halo as it develops). By 18:50 UT, the C2 occulting disk seems to be completely covered, though the signal is extremely faint on the western hemisphere. The event is first seen in C3 at 17:42 UT above the NE Limb, developing afterward as a very asymmetric halo CME. The mean plane-of-sky of the LE of the event at PA ~ 25 was ~ 744 km/sec (based on C3 data). GOES reported an M4.9 X-ray flare on NOAA AR 10786 (N09E03) between 16:07 - 16:40 UT with peak emission at 16:29 UT. For completeness, note that there was also a C2.7 X-ray flare on NOAA AR 10789 (N17E44) between 14:37 - 15:34 UT with peak emission at 15:19 UT. EIT 195 images show a relatively strong brightening starting at ~ 16:12 UT on AR 10786. A dimming region to NE of AR 10786 can be seen afterward. Corresponding running difference images show an intensity disturbance traveling mainly toward N of the AR. In summary, the event has therefore been determined as a rather asymmetric full halo CME, frontsided, associated with an M4.9 X-ray flare on NOAA AR 10786. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050707. 22:06 NE - Faint and asymmetric expanding loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 08-Jul-2005: ************ 07:27 NE - Elongated loop front developing toward ENE. It fade throughout C3. 07:27 ESE - Slow development of a system of faint loops. Difficult to give an exact time of first appearance. 12:26 E - Faint front developing slightly toward ESE (partly superposed in the LOS with the development of the system of faint loops). It fades close to the inner edge of C3. 17:31 N - Extremely faint and diffuse front. Next C2 image available Partial (19:22 UT) shows a very faint expanding system of loop-like Halo fronts developing mainly toward N. A bright ragged front is also developing toward W, which does not form part of the partial halo under analysis (se below). The partial halo event was first seen in C3 at 19:42 UT above the N Pole. By 00:18 UT (on 07/09), the event spans ~ 150 deg, from around PA 280 - 070. It is difficult to precise the limit on W, as the faint halo event superposes there in the LOS with the brighter limb event described above (see also below). The mean plane-of-sky speed of the LE of the partial halo event at PA ~ 3 was ~ 461 km/sec (based only on the first four C3 frames, as the LE becomes then barely discernible). GOES reported a long duration C1.6 X-ray event on NOAA AR 10786 (N13W11) between 15:40 - 17:19 UT with peak emission at 16:18 UT. EIT 195 images show the development of a dimming region to N of the AR 10786, starting at around 16:12 UT. Please note that the Telemetry Submode changed from Submode 5 to 6 by 15:00 UT and therefore the EIT 195 CME watch changed from half-res (512x512) to full-res (1024x1024) by that time. Note that by 17:15 UT, a barely backsided CME starts to be seen developing above the WSW Limb. This signature likely corresponds to the EIT counterpart of the ragged front seen in C2/C3 images developing toward W mentioned above. In summary, the event has therefore been determined as a very faint partial halo CME, frontsided, associated with a long duration C1.6 X-ray flare on NOAA AR 10786. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050708. 19:22 W - Bright ragged loop front. Some infalling material (see previous event for some other details). ---------------------------------------------------------------------------------- 09-Jul-2005: ************ 02:30 NNE - Extremely faint expanding loop front. It fades close to the inner edge of C3. 09:06 E - Small front. 13:31 SE - Expanding 'half' loop fronts. They fade throughout C3. 13:31 W - Narrow and elongated front. It fades throughout C3. 21:54 ENE - Bright loop-like front followed by a cavity and bright inner core. See next event for some other details on this event. 22:30 NW - Wide and ragged loop front front. Faint and diffuse extensions Asymmetric all above both poles can also be discerned. By 23:06 UT, the C2 Halo occulting disk is already completely covered. Note that the development of a typical 3-part structure CME can be seen on ENE since 21:54 UT (previous entry). Signatures of the halo event were first seen in C3 at 23:18 UT all above the W Limb. A very faint and diffuse front can be seen ahead (shock?) spanning all above the N Pole. The C3 occulting disk is completely covered by 23:42 UT. The mean plane-of-sky speed of the LE of the halo CME (where the intensity gradient is maximum) at PA ~ 306 is around 1140 km/sec, showing practically no acceleration (based on C3 data). GOES reported an M2.8 X-ray flare on NOAA AR 10786 (N12W28) between 21:47 - 22:19 UT with peak emission at 22:06 UT. Note also the occurrence of a C1.5 X-ray flare on NOAA AR 10789 (N17E15) between 20:23 - 21:01 UT with peak emission at 20:45 UT preceded by a B5.8 X-ray flare on the same AR 10789 that peaked at 19:38 UT. EIT 195 images show a small brightening on AR 10789 starting at 20:36 UT with the formation of a dimming region toward NE of the AR afterward. The eruption of at least part of a filament on NE can be seen more or less coincident with the development of the dimming. The EIT events just described are most likely related to the X- ray activity reported by GOES on NOAA AR 10789 (and seem to be the EIT counterpart of the 3-part structure CME seen by the LASCO coronagraphs). Later, at 22:00 UT, a strong brightening can be seen on AR 10786 followed by the formation of a dimming toward NW, N, and NE of the AR. Corresponding running difference EIT 195 images show a strong intensity disturbance developing radially away of the AR, mainly toward N. The bulk of the material ejected seems to develop mainly toward NW. These EIT events are related to the M2.8 X-ray flare on AR 10786. In summary, the event has therefore been determined as an asymmetric full halo event, frontsided, associated with an M2.8 X-ray flare on NOAA AR 10786. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050709. ---------------------------------------------------------------------------------- 10-Jul-2005: ************ 06:06 W - Diffuse front that quickly fades. 08:30 WSW - Diffuse brightening precedes a big and bright loop front at 08:54 Asymmetric UT. By 09:30 UT, faint extensions can be seen pushed toward N, Halo past the N Pole. Much gusty outflow then on W. The event is first seen in C3 at 09:42 UT (note that a narrow front, most likely the preceding diffuse front, can already be seen by 09:18 UT). Faint extensions start to be seen above the N Pole by 10:23 UT. By 11:18 UT, rather circular extensions develop all above the NE limb (most likely signatures of a shock). The shock makes the event to look like a very faint (and asymmetric) full halo CME. The mean plane-of-sky speed of the LE at PA 254 was ~ 900 km/sec (based on C3 data). EIT 195 running difference images show a big CME developing all above the W limb, starting at 08:00 UT on WSW. The source region seems to be a couple of days behind the limb. No significant X-ray events were reported by GOES by the time of this event. In summary, the event has therefore been determined as a very faint and asymmetric halo event, most likely backsided. 12:54 WSW - Diffuse and elongated loop-like front. It fades throughout C3. 15:54 WNW - Initially bright ragged loop front. It fades throughout C2. Gusty outflow continues. EIT 195 running difference images show an important intensity disturbance, starting at 15:24 UT, right above the W limb. It is then seen developing toward WNW. GOES reported a C9.9 X-ray flare on NOAA AR 10783 (N00W90) between 15:08 - 15:20 UT with peak emission at 15:16 UT. 19:31 W - Diffuse loop-like front developing slightly toward WSW. 23:06 W - Bright loop front with twisted inner structure. Much gusty outflow afterward. ---------------------------------------------------------------------------------- 11-Jul-2005: ************ 00:30 W - Just after the event reported to start at 23:06 UT, an apparently new bright and ragged front appears. Much gusty outflow then continues. 05:30 WNW - Initially bright and relatively small loop front. It fades close to the iner edge of C3. 06:54 W - Initially bright and relatively small loop front that quickly fades. Much gusty outflow continues. 13:54 WNW - Another initially bright and relatively small loop front. 17:06 W - Initially bright (and wider than previous fronts on W-WNW) loop front. Gusty outflow continues. It fades throughout C3. 20:54 WNW - Faint ragged front that fades throughout C2. 23:54 WNW - Faint ragged front that quickly fades. **** NOTE: **** The activity seen on the W-WNW limb is most likely associated with **** X-ray activity on NOAA AR 10786 (in average around N10W50): GOES **** reported multiple B- and C-class X ray flares on AR 10786 all along **** the day. ---------------------------------------------------------------------------------- 12-Jul-2005: ************ **** NOTE: **** NOAA AR 10786 continues with C-class X-ray activity along the day. **** Also a couple of M X-ray flares. 04:54 WNW - Elongated and diffuse ragged loop-like front in the gusty outflow. 05:30 W - Bright and ragged loop front at roughly the PA of the southern leg of previous event. Much gusty outflow continues. 13:31 WNW - Initially bright ragged front that quickly fades. The slow development of a system of loops follows. 16:54 WNW - Bright loop front that superposes in the LOS with the pre- Asymmetric existent slow development of a system of loops. It is Halo immediately followed by another bright front on W. It becomes difficult to separate both fronts in the C2 FOV. By 19:31 UT, extremely faint extensions can be seen above the N Pole (shock), apparently surrounding the C2 occulting disk shortly afterward. The event is first seen in C3 at 17:42 UT, just appearing above the W Limb. During its evolution in C3, the two apparently different fronts can be discerned: i) one developing slightly toward WNW a little bit ahead (Front #1), and ii) another one apparently wider developing toward W (Front #2). They both can be seen preceded by a very faint front ahead. It is not until 22:18 UT that extremely faint extensions can be seen above the N Pole. They are afterward barely discernible. The mean plane- of-sky of the LE of Front #1 at PA 292 was ~ 525 km/sec, and of Front #2 at PA 294 was 420 km/sec (based on C3 data). GOES reported multiple C-class (increasing) X-ray activity all along the day, as well as several M-class X-ray flares on NOAA AR 10786. In particular: . an M1.0 (N12W69) between 12:47 - 13:25 UT, peaking at 13:06 UT, . a long duration M1.5 (N09W67) between 15:47-18:07 UT, peaking at 16:24 UT, and . an M1.3 (N09W72) between 22:35 - 23:02 UT, peaking at 22:52 UT. Note that the long duration M1.5 X-ray flare was preceded by an impulsive C2.3 X-ray flare on the same AR (N12W71) between 15:33 - 15:40 UT, with peak emission at 15:37 UT. EIT 195 running difference images show a small brightening in the northern portion of AR 10786 at 15:36 UT followed by a strong brightening at 16:00 UT just a little bit to S. An intensity disturbance (wave) centered on the AR is seen developing afterward. It can clearly be seen traveling across the disk toward E. A dimming to N and S of the AR can also be seen. Note that it is the shock what could make the LASCO event associated to the long duration X-ray flare on AR 10786 to be geoeffective. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050712. 19:54 W - Ragged loop front in the trail of previous event. 23:30 W - Bright and ragged loop front. GOES reported an M1.3 X-ray flare on NOAA aR 10786 (N09W72) between 22:35 - 23:02 UT with peak emission at 22:52 UT. Gusty outflow continues. ---------------------------------------------------------------------------------- 13-Jul-2005: ************ **** NOTE: **** High Activity on NOAA AR 10786 continues. 02:54 WNW - Bright loop front with inner structure preceded by a bright and narrow feature. Some very faint extensions to N and S. Gusty outflow continues. GOES reported an M1.1 X-ray flare on NOAA AR 10786 (N11W82) between 02:35 - 03:47 UT with peak emission at 03:16 UT. It was preceded by a C4.2 X-ray flare (N11W77) that peaked at 01:38 UT. 10:30 SSE - Diffuse jet-like front. 12:54 W - Bright ragged loop front. See next event for more details. 14:30 WNW - Very bright loop front that partly superposes in the LOS with a Asymmetric previous bright loop front (which was first seen at 12:54 UT). Halo "Our" event develops as a big loop front with faint extensions toward N and S (shock). The faint extensions surround completely the C2 occulting disk by 15:54 UT. Much gusty outflow then on WNW. "Our" event is first seen in C3 at 14:42 UT, just appearing above the WNW Limb, still behind the previous front mentioned above. By the time of the next frame (15:18 UT), "our" event already surpasses the previous front. The C3 occulting disk appears to be completely covered by 16:42 UT by the faint extensions. The mean plane-of-sky of the LE at PA 290 was around 1360 km/sec (based on C3 data), showing practically no acceleration. GOES reported three M-class X-ray flares on NOAA AR 10786 on 2005/07/13 by the time this report was written. The first one, an M1.1 (on N11W82) peaking at 03:16 UT, was not directly related to the LASCO/EIT events under analysis in this report. The other two were: i) an impulsive M3.2 (N08W79) between 12:03 - 12:24 UT, peaking at 12:19 UT, and ii) a long duration M5.0 (N11W90) between 14:01 - 15:38 UT, peaking at 14:49 UT. The M3.2 X-ray flare is most likely associated with the front first seen in C2 at 12:54 UT, while the long duration M5.0 X-ray flare is the one associated with "our" event (event first seen in C2 at 14:30 UT). EIT 195 running difference images show a relatively strong brightening starting at 12:12 UT and peaking in next frame at 12:24 UT on AR 10786, right on the limb (EIT counterpart of the M3.2 X-ray flare). A nice CME signature moving outward can be seen afterward. By 12:48 UT, the expansion of a system of loops apparently anchored right behind the limb starts to be seen. The expansion becomes suddenly accelerated by the time of a strong brightening starting on AR 10786 at 14:24 UT (EIT counterpart of the M5.0 X-ray flare). An important intensity disturbance traveling across the disk toward East can be seen afterward. In summary, the event has therefore been classified as a limb event associated with an M5.0 X-ray flare. Its associated shock made it appear as a faint an asymmetric full halo event. Note that it is the shock the one which could make the event partly geoeffective. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050713. **** NOTE: **** GOES reported an impulsive M1.2 X-ray flare on NOAA AR 10786 (N08W82) **** between 19:02 - 19:13 UT with peak emission at 19:09 UT. No clear **** signatures of an associated CME can be discerned in C2, other than **** strong gusty outflow by the time on WSW - WNW. 22:06 W - Diffuse front just appearing. It develops toward WSW as a bright and ragged loop front with faint and diffuse loop-like extensions toward N. Gusty outflow then continues on WSW - WNW. GOES reported another impulsive M1.2 X-ray flare on NOAA AR 10786 (N07W86) between 21:49 - 21:58 UT with peak emission at 21:54 UT. At 22:00 UT, EIT 195 images show a brightening on AR 10786 and a CME signature above the WSW Limb. ---------------------------------------------------------------------------------- 14-Jul-2005: ************ 00:54 SSE - Diffuse jet-like front. 02:54 WSW - Bright and narrow front with faint loop-like extensions toward N. GOES recorded a C3.8 X-ray flare on NOAA AR 10786 (N08W87) between 01:48 - 01:57 UT with peak emission at 01:53 UT. 04:54 WSW - Another bright and narrow front with faint loop-like extensions toward N. GOES recorded an M1.0 X-ray flare on NOAA AR 10786 (N10W86) between 03:02 - 03:28 UT with peak emission at 03:23 UT. 05:54 WSW - Another bright and narrow front (brighter and slightly bigger than the previous ones) with faint loop-like extensions toward N. GOES recorded a C2.2 X-ray flare on NOAA AR 10786 (N07W89) between 05:23 - 05:31 UT with peak emission at 05:23 UT. 06:30 WNW - Bright and ragged loop front that apparently comprises two fronts: i) one developing toward W (Front [1]), and ii) another one, a little bit "elongated", developing slightly toward WNW (Front [2]). They are followed at 07:54 UT by another bright and ragged loop front (Front [3]) that is first seen when it is already half way to the end of the C2 FOV. It develops apparently faster than the other two fronts. The events in the C3 FOV show up as one wide loop front developing toward W first seen at 07:42 UT (Front [1]) immediately followed by the Front [3] at 08:18 UT. Afterward it becomes difficult to separate both events. Also by 08:18 UT starts to be discernible the Front [3] on WNW (roughly at a PA that matches that of the northern leg of the wide loop front). This loop on WNW can be tracked running behind the complex front [1]-[3], though later seems to be pushed from behind by the following event (see next entry --> 10:30 UT). The mean plane-of-sky speed of the LE of the complex Front [1]-[3] at PA 274 was ~ 737 km/sec. GOES reported an M9.1 X-ray flare on NOAA AR 10786 (N07W89) that peak at 07:25 UT during a long duration X-ray event that started at 05:57 and was reported to finish at 07:29 UT. EIT 195 running difference images show a brightening right on the W limb at 06:12 UT followed by a much stronger brightening at 07:26 UT. A faint intensity disturbance can be seen traveling on the disk toward E. 10:30 WNW - Extremely small brightening just appearing that develops as an Asymmetric extremely bright, big, and wide loop front by the time of the Halo next C2 frame (10:54 UT), the LE already reaching the end of the C2 FOV on W. Faint and diffuse extensions develop to N. By 11:30 UT, the C2 occulting disk is completely covered. The event is first seen in C3 at 11:18 UT, the LE on W already at ~ 10.2 solar radii. It appears very bright on W with diffuse extensions spanning all above the N Pole. The C3 occulting disk is covered by 12:42 UT. By that time, the LE on W is already at ~ 21 solar radii. Note that this event develops in the aftermath of a previous big and complex event associated with an M9.1 X-ray flare (peak at 07:25 UT) that was first seen in C2 at 06:30 UT (see previous entry). The mean plane-of-sky speed of the event under analysis in this report at PA 280 was ~ 2280 km/sec (based on only the first two C3 frames). After the first two frames, the event gets close to the LE of previous event and therefore starts to slow down (it becomes more difficult to precise the location of the LE). If considered all the C3 frames available at the time of writing, the mean plane-of-sky speed becomes ~ 1430 km/sec at PA 277, showing a marked deceleration. GOES reported a long duration X1.2 X-ray flare on NOAA AR 10786 (N10W89) between 10:16 - 11:29 UT with peak emission at 10:55 UT. The high energy proton fluxes (>10 Mev) that started to gradually increase by ~ 16:00 UT on 2005/07/13 (~ two hours after the M5.0 X-ray flare) suffered another increase about 1 hour after the peak of the X1.2 X-ray flare, most likely associated with the interaction of the CME event under analysis in this report with the previous one already under development. EIT 195 running difference images show a strong brightening starting at 10:24 UT immediately followed by the signature of a big CME developing all above the western limb jointly with an intensity disturbance traveling across the disk toward E. In summary, the event has therefore been classified as a limb event associated with a X1.2 X-ray flare. Its associated shock made it appear as an asymmetric full halo event. Note that it is the shock the one which could be partly geoeffective. The development of "our" CME event is profoundly affected by the CME event associated to the M9.1 X-ray event. Therefore, it is a complex event what will be dealing with at the time of the shock arrival at Earth. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050714. 12:06 W - Bright ragged loop front developing slightly toward WSW in the aftermath of previous halo CME. 13:31 W - Another ragged front followed by a fainter one at 14:54 UT. Much gusty outflow continues. 16:54 W - Very narrow front followed by a diffuse brightening precedes a bright and ragged loop front at 17:54 UT. By around 18:54 UT, an asymmetric and ragged (wider) loop front follows. By around that time, a gradual increase of solar protons starts to be discerned in LASCO images. GOES reported on NOAA AR 10786 i) a C7.3 X-ray flare (N10W90) between 16:29 - 16:39 UT with peak emission at 16:34 UT, and ii) an M1.3 X-ray flare (N09W90) between 17:16 - 17:28 UT with peak emission at 17:25 UT. 23:30 W - Initially bright loop front developing slightly toward WSW. It fades throughout C3. GOES reported an M1.1 X-ray flare on NOAA AR 10786 (N09W90) between 22:50 - 23:02 UT with peak emission at 22:57 UT. ---------------------------------------------------------------------------------- 15-Jul-2005: ************ 00:54 ESE - Faint jet-like front preceding an elongated loop-like front at 02:30 UT. The loop front fades throughout C3. 02:30 W - Bright loop front developing slightly toward WSW. Much gusty outflow continues all above the W Limb. 08:30 ESE - Very diffuse and elongated loop-like front. 09:06 WNW - Diffuse brightening just appearing, develops as a not-well- defined front. It is followed at 09:54 UT by a ragged loop front developing toward W. 11:54 WNW - Bright and ragged loop front develops as a nice balloon-type CME (with twisted inner structure). Gusty outflow continues. 16:06 W - Elongated and bright front developing slightly toward WSW. Gusty outflow continues. 20:06 WNW - Faint front just appearing. It develops as a bright loop front, followed (at 20:54 UT) by a wider and bright loop front which in turn is followed by a bright inner structure. By 22:30 UT, faint extensions (apparently deflected structures) can be seen above the S Pole. The event is seen in C3 at 21:18 UT above the WNW Limb with faint extensions developing then above the S Pole (they do not seem to surround the occulter). EIT 195 images show, starting at around 19:13 UT, the slow expansion of a system of loops on WNW (apparently anchored barely behind the limb on NOAA AR 10786). By 20:48 UT, the expansion accelerates. GOES reported a long duration C6.5 X-ray flare above NOAA AR 10786 (almost behind the limb) starting at 20:08 UT (Source: BBSO Active Region Monitor). In brief, the event is clearly a limb event. Its associated shock gives the appearance to the event of, at least, a faint partial halo. ---------------------------------------------------------------------------------- 16-Jul-2005: ************ 00:06 W - Small front develops as a relatively bright and ragged loop front slightly toward WSW. Gusty outflow continues. EIT show a strong CME signature with source region nearby AR 10790 by the end of previous day. 01:32 ENE - Slow development of a faint system of loops along streamer. Pseudo-continues outflow superposed in the LOS. 13:54 WNW - Initially bright ragged front that quickly fades in the gusty outflow. 19:31 E - Extremely faint front starts to be discernible above the E Limb in C2 (though it is difficult to precise the exact time) partly superposed with the pre-existent development of a faint system of loops on ENE. Our front develops then in C2 as a very faint (and slow) full halo CME (though extremely faint on W). It is first seen in C3 just appearing above the E Limb at 23:18 UT (the part of the event on W, if any, is not discernible in C3). By 06:42 UT (on nxt day), the event is barely discernible (the LE on W just by 11.5 solar radii). No clear signatures of any frontsided event can be seen on EIT 195 images by the time. ---------------------------------------------------------------------------------- 17-Jul-2005: ************ 00:06 SE - Slow development of a faint system of wide and expanding loops. Difficult to give an exact time of first appearance. 00:54 W - Fan-like front immediately followed a little bit to N by a diffuse and elongated loop-like front. They fade throughout C3. 04:06 W - Ragged loop front that fades throughout C3. 07:32 W - Bright and narrow front followed at 09:54 UT by a bright and ragged front. By 10:34 UT, an initially bright ragged loop front follows, developing slightly toward WNW. The three fronts are then quickly surpassed by the following halo event. 11:30 NW - Very strong loop-like front partly superposed with previous Asymmetric event (see entry at 07:32 UT). By 11:54 UT, faint loop-like Halo extensions can be seen all above the S Pole, the C2 occulting disk being completely covered by 12:06 UT. By that time, the LE of the event on W is already past the outer edge of the C2 FOV, while the halo extensions on E are just above the limb. Much gusty outflow then on the W-WNW Limb. The event is first seen in C3 at 12:18 UT, as a very bright loop front on NW surrounded by faint and diffuse extensions that almost cover completely the C3 occulting disk (which is then fully surrounded by 12:42 UT). The mean plane-of-sky speed of the LE of the event (outermost front) at several PA is given below (based on C3 data): . PA 049: 1060 km/sec . PA 232: 1340 km/sec . PA 304: 1453 km/sec . PA 350: 1364 km/sec showing practically no acceleration (in all four cases). GOES reported multiple B-class activity during the day on NOAA ARs 10790 (in average at S10W90) and 10789 (in average at N13W90) plus an impulsive C4.3 X-ray flare on AR 10790 (S10W90) that peaked at 06:29 UT. They do not seem to be directly associated with the big halo under analysis, as observed in the EIT 195 images. EIT 195 running difference images show signatures of a big CME with source region behind the limb (most likely nearby the actual location behind the disk of the already gone 10786). It starts to be clearly seen by 10:50 UT as the expansion of a loop front above the WNW limb, which seems to break up by 11:36 UT. A big intensity disturbance to N and S above the limb (as well as partly on the most western part of the disk) can be seen afterward. In summary, the event has therefore been classified as a strong and asymmetric full halo event, backsided. Note that after ~ 14:00 UT, a slight and gradual increase of energetic particles hitting the CCD can be seen in the C2 images. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050717. 13:54 W - In the aftermath of the Halo CME, the slow development of a faint system of loops can be seen. Difficult to give an exact time of first appearance. ---------------------------------------------------------------------------------- 18-Jul-2005: ************ **** NOTE: **** Much gusty outflow and small ragged fronts on ENE and ESE since late **** on previous day all along the day and well into next day. 00:30 WNW - Faint loop front in the gusty outflow. It fades throughout C3. 04:30 ESE - Not-well-defined front. It fades throughout C3. 09:54 ESE - Diffuse front followed by a narrow front a little bit to S. They fade throughout C3. 11:30 W - Very diffuse and elongated faint loop front. 21:08 ESE - Small front followed by a very faint system of expanding loops (in the form of a pseudo-continuous outflow). It later superposes in the LOS with the slow development of another system of loops (see next entry). 22:30 ESE - Slow development of a system of loop-like fronts that evolves as a big twisted structure (toward SE), partly superposed in the LOS with the trailing material of event reported to start at 21:08 UT. ---------------------------------------------------------------------------------- 19-Jul-2005: ************ **** NOTE: **** Still much gusty outflow on ENE (all along the day), rotating toward NE. 04:06 ENE - Diffuse jet-like front. 05:08 WNW - Very faint asymmetric loop front developing toward W. It fades throughout C3. 11:54 NE - Extremely faint and diffuse (not well defined) front that fades throughout C3. 17:30 NNE - Very faint kind-of half loop front. Difficult to give an exact time of first appearance. It fades throughout C3. 19:54 NE - Diffuse jet-like front followed a little bit to N (at ~ 20:58 UT) by a narrow loop front. ---------------------------------------------------------------------------------- 20-Jul-2005: ************ 08:54 W - Faint, (initially) loop-like front that quickly fades. 08:54 ENE - Initially bright front develops as an asymmetric loop front. **** No LASCO C2/C3 CME watch images between 15:00 - 17:00 UT due to **** **** the Faraday Rotation Study with Cassini Campaign (high cadence **** **** C3 PBs subfield images during this time). **** 17:07 N - Faint and diffuse front followed at 18:30 UT by another one on NNE. 21:30 N - A faint and diffuse wide loop front develops, moving apparently faster than previous event. ---------------------------------------------------------------------------------- 21-Jul-2005: ************ 03:54 HALO - The event was first seen in C2 at 03:54 UT as a very bright loop- like front spanning all above the NW, N Pole, NE, and E Limb. Faint and diffuse extensions can be seen all around the C2 occulting disk, though they are extremely faint above the S Pole. The main loop front develops in the C2 FOV toward N with its legs apparently anchored on the W and ESE limbs. The event is first seen in C3 at 04:18 UT, very bright on NE, with faint and diffuse circular extensions already surrounding completely the C3 occulting disk. The mean-plane-of-sky speed for different features of the event at several position angles is given below (based on C3 data): - LE of the diffuse front at: . PA 000: 1484 km/sec . PA 035: 1471 km/sec . PA 180: 1230 km/sec (LE rather faint and diffuse) . PA 275: 1160 km/sec (LE rather faint and diffuse) - LE of the bright loop front developing mainly toward NE, at PA 040: 1160 km/sec showing practically no acceleration (in all cases). GOES reported extremely low X-ray activity during the day (A-class). The disk of the Sun is spotless. Likewise, EIT 195 images do not show any significant activity on the disk. Only likely signature of the event is an extremely faint intensity disturbance that seems to propagate all above the limb in the northern hemisphere starting at around 03:24 UT. In summary, the event has therefore been classified as a strong full halo event, backsided. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050721. 08:54 NW - Extremely faint and wide loop front. Not discernible in C3. 09:08 NE - Faint and diffuse front followed at 10:06 by an (slightly brighter) elongated loop front. The latter fades throughout C3. Gusty outflow. 12:30 N - Diffuse jet-like front. 13:31 W - Ragged loop front. **** No LASCO C2/C3 CME watch images between 15:00 - 17:00 UT due to **** **** the Faraday Rotation Study with Cassini Campaign (high cadence **** **** C3 PBs subfield images during this time). **** 17:07 NW - Extremely faint loop front that fades throughout C2. 18:06 W - Diffuse front that fades throughout C3. It is followed at 19:31 UT by a very faint, diffuse, and wide loop front all over the S Pole, which seems to develop apparently fully surrounding the C2 occulting disk. Barely discernible in C3, and only close to the inner edge of its FOV. 18:30 NE - Very faint and diffuse loop-like front. It fades throughout C3. 23:30 W - Initially bright ragged loop front with structured interior. ---------------------------------------------------------------------------------- 22-Jul-2005: ************ 01:54 NE - Very faint and elongated loop-like front. 02:30 SE - Extremely faint and wide loop front. Just barely visible in C3 only very close to the inner edge of its FOV. 06:30 NE - Ragged blob-like front in the gusty outflow. 09:54 E - Diffuse and elongated loop-like front. **** No LASCO C2/C3 CME watch images between 15:00 - 17:00 UT due to **** **** the Faraday Rotation Study with Cassini Campaign (high cadence **** **** C2 PBs subfield images during this time). **** 17:30 S - Extremely faint (almost circular) front spanning all the way from ENE, E, SE, S, SW, and NW, already under way after the gap. The event is first seen in C3 at 17:42 UT, above the SE Limb, fading out by around 20:25 UT. No significant X-ray activity was reported by GOES during the day (A-class). 17:54 NE - Ragged and elongated loop front. It fades throughout C3. 23:54 SE - Diffuse front on SE, with very faint and even more diffuse HALO extensions above the E Limb, S Pole, and south western limbs. The bulk of the CME is seen developing then toward South, with very faint extensions (shock) above the N Pole. The event is first seen in C3 on 2005/07/23 at 01:42 UT, all above the eastern limb, S Pole, and western limb. Extremely faint extensions above the N Pole make the event to look like a symmetric full halo event, though the bulk of the CME seems to develop mainly toward S. The mean-plane-of-sky speed of the LE of the event at i) PA 128 was ~ 470 km/sec, and at ii) PA 212 was ~ 400 km/sec. GOES reported extremely low X-ray activity by the time of the start of the event (A-class). Likewise, EIT 195 images do not show any significant activity on the disk. In summary, the event has therefore been classified as a full halo event, backsided. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050723. ---------------------------------------------------------------------------------- 23-Jul-2005: ************ 04:54 NE - Elongated and relatively narrow loop front. Inflows all above the eastern limb. 09:30 NE - Small and diffuse brightening develops as a ragged loop front. It is followed at 10:06 UT by another ragged loop front. 12:30 ESE - Diffuse and ragged loop front that partly superposed in the LOS with the trailing material of previous event. **** No LASCO C2/C3 CME watch images between 15:00 - 17:00 UT due to **** **** the Faraday Rotation Study with Cassini Campaign (high cadence **** **** C2 PBs subfield images during this time). **** 17:43 ENE - Faint and asymmetric expanding loop front already under development (C3 time) in C3 after the gap. 19:54 ENE - Small and narrow brightening develops as a bright loop front. The event is surpassed in the C3 FOV by the event reported to start at 23:30 UT. 20:58 NW - Extremely faint and diffuse wide front that apparently fades throughout C2. 23:30 ENE - Bright and ragged front develops as an asymmetric front expanding toward N. By 00:43 UT on next day, the event spans up to past the N Pole. It moves faster than the event reported to start at 19:54 UT, surpassing it in the C3 FOV by around 03:18 UT. ---------------------------------------------------------------------------------- 24-Jul-2005: ************ 04:54 ESE - Faint and diffuse expanding loop front. It fades close to the inner edge of C3. 11:30 ESE - Bright loop front develops as at least a Partial Halo Event. By Partial 11:54 UT, faint extensions span up to above the N Pole. By 12:43 Halo UT, the whole event spans in C2 about 210 deg (approximately from PA 310 - 160). It was first seen in C3 at 11:42 UT just appearing above the ESE limb. The mean plane-of-sky speed of the LE of the bulk of the CME (not the diffuse front ahead, as it was too diffuse for an accurate measurement) was ~ 960 km/sec at PA 112. The event was apparently surpassed by the Full Halo Event (see next entry) during the C3 gap. EIT 195 images do not show frontsided activity during the time of the start of the event. A faint CME signature can be seen however above the E limb by around 11:12 UT. This event is catalogued therefore as at least a partial halo event, backsided. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050724. 13:54 E - Bright and ragged loop front develops as a Full Halo Event in Asymmetric the aftermath of the "at least" Partial Halo Event reported to Halo start at 11:30 UT. The loop front develops as an expanding and bright loop front toward E, surrounded by diffuse extensions. The C2 occulting disk appears to be fully surrounded by 14:30 UT. Unfortunately, there are no C2 CME watch images between 15:00 - 17:00 UT (last C2 image before the gap at 14:30 UT, first one after the gap at 17:07 UT), because of special C2 observations (only PBs subfield images) for the Faraday Rotation Study (with Cassini). The event is first seen in C3 at 14:18 UT, all above the eastern limb. The next C3 image (17:18 UT) shows the LE on E apparently past the outer edge, with faint extensions above the western limb. Due to the lack of C3 images between 15:00 - 17:00 UT, it becomes practically impossible to determine the mean plane-of-sky speed of the LE on C3. Therefore, using only two C2 frames and one C3 frame, the mean plane-of-sky speed was about 2500 km/sec at PA 081, showing practically no acceleration. GOES reported extremely low X-ray activity during the whole day (A-class). Likewise, EIT 195 images do not show any significant activity on the disk. However, it does show an important (backsided) CME signature above the E Limb, starting at around 13:36 UT. In summary, the event has therefore been classified as a strong and asymmetric full halo event, backsided. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050724. **** No LASCO C2/C3 CME watch images between 15:00 - 17:00 UT due to **** **** the Faraday Rotation Study with Cassini Campaign (high cadence **** **** C2 PBs subfield images during this time). **** 17:30 E - In the gusty outflow left by the Halo event, a ragged loop front becomes discernible. 22:30 E - Bright and ragged loop front above the E Limb with very faint Asymmetric and diffuse extensions to N and S. The ragged loop front Halo develops toward ESE, the C2 occulting disk being fully covered by the extensions by ~ 23:54 UT (by that time the LE on E is well past the outer edge of the C2 FOV, while on W-SW the extensions are just above the inner edge of C2). The event is first seen in C3 at 23:18 UT, all above the E-ESE limb. Faint expanding extensions can be seen then to S, and up to past the N Pole. Though the C3 disk becomes apparently fully covered by 02:18 UT, the signal is extremely faint on SW. The mean plane- of-sky speed of the ragged LE at PA 098 was ~ 650 km/sec. GOES reported extremely low X-ray activity during the 24th and 25th of July (A-class). Likewise, EIT 195 images did not show any significant activity on the disk. In summary, the event has therefore been classified as a very asymmetric full halo event, backsided. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050724b. ---------------------------------------------------------------------------------- 25-Jul-2005: ************ ENE - Much gusty ouflow in the form of small ragged fronts (aftermath of Partial Halo CME that started on previous day at 22:30 UT). 01:31 NNE - Faint, elongated and expanding (toward the N Pole) loop front. It fades throughout C3. 11:06 E - Ragged front just appearing above the E Limb. By 11:30 UT, the LE Asymmetric of the ragged front (now seen as a wide and ragged loop front) Halo already reached the outer edge of C2. Faint extensions reach the W limb by 11:54 UT, the C2 occulting disk being fully covered by 12:43 UT (the signal is again extremely faint above the SW limb). The event is first seen in C3 at 11:18 UT, just appearing above the E Limb. By 11:42 UT faint extensions cover both the N and S poles. The C3 occulting disk is fully covered by 12:18 UT. The mean plane-of-sky speed of the LE at PA 068 was ~ 1590 km/sec. GOES reported extremely low X-ray activity during the day (A- class). Likewise, EIT 195 images did not show any significant activity on the disk. However, it did show signatures of an important backsided CME all above the E Limb starting at around 11:00 UT. In summary, the event has therefore been classified as an asymmetric full halo event, backsided. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050725. **** No LASCO C2/C3 CME watch images between 15:00 - 17:00 UT due to **** **** the Faraday Rotation Study with Cassini Campaign (high cadence **** **** C2 PBs subfield images during this time). **** 17:30 NE - Faint, elongated, and expanding loop front already under development after gap, followed by another one starting at around 17:30 UT. 21:54 E - Very bright ragged loop front. Faint and diffuse extensions to N and S. By 23:30 UT, faint extensions can be seen past the N Pole up to the W Limb. The extensions on the western hemisphere are barely visible in C3 and only close to its inner edge. The mean plane-of sky speed of the ragged LE at ~ PA 90 was about 1480 km/sec, showing practically no acceleration. GOES reported no significant X-ray activity on the disk during the day. Likewise, EIT 195 images do not show significant activity on the disk by the time of the event. However, it does show signatures of a backsided CME above the E Limb, starting at 21:36 UT. ---------------------------------------------------------------------------------- 26-Jul-2005: ************ 03:54 ENE - Jet-like front surpassed in the C2 FOV by following event. 04:54 ENE - Very bright and wide ragged loop front. Faint and diffuse extensions to N and S. As it happened with event at 21:54 on previous day, faint extensions can be seen past the N Pole up to the W Limb by 05:30 UT. An extremely weak signal can be seen on SW by 06:30 UT. Signatures of the event in the western hemisphere are practically non-discernible in C3. The mean plane-of sky speed of the ragged LE at ~ PA 85 was ~ 1290 km/sec, showing practically no acceleration. Again, EIT 195 images do not show significant activity on the disk by the time of the event. But it does show a backsided CME above the ENE limb starting by 04:24 UT. 09:30 E - Bright loop front just appearing develops as a very bright ragged Partial and wide loop front with faint and diffuse extensions to N and S. Halo By 09:54 UT, the LE on E is already past the outer edge of the C2 FOV. The brightest structure develops toward ESE. The event is first seen in C3 at 09:42 UT, just appearing above the E Limb. By 10:19 UT, faint extensions surround the main structure, on S well past the S Pole. The angular extent of the event at 11:42 UT is about 230 deg (from PA 005 - 235), extremely faint on SW. Note that the last C3 image where the event can be seen is at 14:18 UT (there is afterward a gap between 15:00 - 17:00 UT due to the especial PBs images for the Faraday Rotation Study still under way). The mean plane-of-sky speed of the ragged LE at PA 082 was ~1800 km/sec (based on only the first 3 C3 frames were the event is seen, as the LE becomes then too faint and diffuse for accurate measurements). EIT 195 images do not show significant activity on the disk that could be related to the event by the time of the event. However, it does show signatures of an important (and still backsided) CME above the E Limb, first clearly seen at 09:24 UT. In summary, the event has therefore been classified as at least a Partial Halo event, backsided. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050726. **** No LASCO C2/C3 CME watch images between 15:00 - 17:00 UT due to **** **** the Faraday Rotation Study with Cassini Campaign (high cadence **** **** C3 PBs subfield images during this time). **** 17:06 E - Asymmetric loop front already under way after gap. 17:06 WNW - Big twisted structure already under way after gap (LE past the outer edge of the C2 FOV). 23:30 ENE - In the gusty outflow, a small ragged front becomes discernible. ---------------------------------------------------------------------------------- 27-Jul-2005: ************ 01:31 WNW - Bright and elongated ragged loop front. EIT 195 images show signatures of a backsided CME above the ENE limb (developing toward NW) starting at 01:13 UT. 04:54 E - Bright loop front. Faint and diffuse extensions to N and S can Asymmetric be seen by 05:08 UT. By 06:06 UT, the C2 occulting disk appears Halo fully covered (by that time, the LE on E is already well past the outer edge of C2). Prominence material follows the outer front on ENE. Note that by 07:54 UT, a new bright loop-like front follows behind the trail of the prominence. The event is first seen in C3 at 05:18 UT as a very bright loop front on E, with faint and diffuse extensions to N and S. By 06:18 UT, the C3 occulting disk seems to be fully surrounded by these faint extensions (though they are very faint on the western hemisphere). The diffuse structures on west that made the C2 occulting disk to appear covered by 06:06 UT, are first seen in C3 by 07:42 UT on W and SW. The mean plane-of-sky speed of the LE of the outermost front at PA ~ 83 was ~ 1960 km/sec, showing practically no acceleration (based on C3 data). GOES reported an M3.7 X-ray flare on N11E90 between 04:33 - 05:30 UT with peak emission at 05:02 UT. The source region is still behind the limb and is apparently located in the position of the old NOAA AR 10786. EIT 195 images show the slow and gradual increase of a system of loops barely anchored behind the limb starting at around 03:48 UT, with a sudden brightening increase at 04:36 UT, just on the ENE limb. By 04:48 UT, the images show release of prominence material, jointly with a strong intensity disturbance all above the eastern limb. A slight intensity disturbance can be seen on the eastern part of the disk afterward. Post-plare loops can also be seen developing just above the limb. By 07:13 UT, another CME signature develops above the ENE Limb (also barely backsided). In summary, the event has therefore been determined as a strong limb event (barely backsided), with an associated shock that made the event to look like an asymmetric full halo event. The event was associated with an M3.7 X-ray flare on the apparently old location of the former NOAA AR 10786 (barely behind the ENE limb). The location of this active region makes the arrival of a CME-produced interplanetary disturbance to the Earth unlikely. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050727. 07:54 ENE - In the trailing material of previous event, a new bright and ragged loop-like front can be seen. EIT 195 images show by 07:13 UT a CME signature developing above the ENE Limb (barely backsided). See previous event for more details. 11:06 ENE - Small and bright ragged front in the southern part of the trailing material of previous event. Gusty outflow continues. GOES reported a C1.7 X-ray flare on N14E88 between 10:31 - 11:30 UT with peak emission at 10:55 UT. **** No LASCO C2/C3 CME watch images between 15:00 - 17:00 UT due to **** **** the Faraday Rotation Study with Cassini Campaign (high cadence **** **** C3 PBs subfield images during this time). **** 17:30 ENE - Faint and ragged loop front already under way after gap. 22:30 E - Faint and elongated loop front preceding following important event. ---------------------------------------------------------------------------------- 28-Jul-2005: ************ 00:30 E - Bright and ragged front immediately followed on ENE by a narrower and also bright ragged front. GOES reported: i) on previous day, a C4.5 X-ray flare on N06E89 between 22:39 - 23:15 UT with peak emission at 23:00 UT, and ii) today, an M1.0 X-ray flare on NOAA AR 10792 (N07E89) between 00:01 - 00:54 UT with peak emission at 00:30 UT. 06:54 ENE - Bright and relatively elongated ragged front. Twisted trailing material. Gusty outflow then all along the day. GOES reported a C2.8 X-ray flare on NOAA AR 10792 (N11E81) between 06:13 - 06:52 UT with peak emission at 06:52 UT. 12:30 WNW - Very slow development of a system of faint loop fronts. Difficult to give an exact time of first appearance. 14:30 SE - Fain jet-like front followed a little bit to S at 15:54 UT by a very narrow loop front. Barely visible in C3 (and only close to its inner edge). By the end of the day, the event develops as a big twisted structure. 20:30 ESE - Faint, narrow and elongated fan-like front that quickly fades. 22:06 E - Bright and ragged loop front. Very faint and diffuse extensions to N and S. First seen in C3 at 00:42 UT on next day, just appearing above the E Limb. Like in C2, very faint and diffuse extensions suuround the main structure to N and S (shock). The shock is practically not discernible on the western hemisphere. The mean plane-of-sky speed of the LE of the event at PA 85 was ~ 1550 km/sec. GOES reported multiple B-class flares all along the day, a couple of C-class flares, and an M1.0 X-ray flare (see previous events) all from NOAA AR 10792. By the time of this particular event, GOES reported an M4.8 X-ray flare on the same AR (N09E82) between 21:39 - 22:24 UT, with peak emission at 22:08 UT. EIT was in 304 A CME watch. A movie of the event in 304 can be seen at: http://umbra.nascom.nasa.gov/eit/movies/eit_20050728_0729_304.mov ---------------------------------------------------------------------------------- 29-Jul-2005: ************ 07:30 SSW - Very faint and diffuse front. 12:06 E - In the gusty outflow, a diffuse and ragged front develops as an asymmetric loop front (brighter to N). It fades througout C3. 17:54 SSW - Slow development of a system of faint loop fronts well into next day. 18:30 ENE - In the gusty ourflow, a just-appearing brightening develops as a not-well-defined and narrow front (seen in C3 as gusty outflow). GOES reported an impulsive C3.4 X-ray flare on NOAA AR 10792 (N12E69) between 17:23 - 17:39 UT with peak emission at 17:32 UT. 20:30 NNW - Extremely faint and diffuse front that fades throughout C2. ---------------------------------------------------------------------------------- 30-Jul-2005: ************ 00:54 ESE - Very faint elongated and ragged loop front. 05:57 ENE - Bright loop front just appearing. See next event for further details. 06:50 ENE - Big and very bright loop front all above the E-ENE limb, almost Asymmetric reaching the end of the C2 FOV, surrounded by faint and diffuse Halo extensions that cover the N and S Poles. Note that an earlier brightening can already be seen on ENE, more precisely at 05:57 UT (more details at the end). The diffuse extensions cover completely the C2 occulting disk by 07:12 UT. Much gusty outflow all above the E Limb afterward. Deflected structures can be seen also by 07:12 UT on SSW. The event is first seen in C3 at 07:00 UT on ENE, with the faint extensions covering the N and S poles. The bulk of the CME develops toward E-ENE. The C3 occulting disk is covered by the diffuse extensions by 07:33 UT (signal just above the limb on the western hemisphere). The mean plane-of-sky speed of the LE of the outermost front of the event at several PA is given below (based on C3 data): . PA 042: 1620 km/sec . PA 075: 1870 km/sec . PA 161: 1150 km/sec GOES reported a couple of X-ray flares on NOAA AR 10792 by the time. In particular: . a C9.4 X-ray flare (on N11E53) between 05:03 - 05:36 UT with peak emission at 05:19 UT, and . an X1.3 X-ray flare (on N12E60) between 06:17 - 07:01 UT with peak emission at 06:35 UT. EIT 195 images show a brightening on AR 10792 by 05:19 UT followed by a dimming. A much strong brightening on the same AR is then seen at 06:44 UT followed by an intensity disturbance that extend all across the disk, as well as all above the eastern limb. Therefore, the brightening first seen in C2 at 05:57 UT is most likely associated to the C9.4 flare, while the X1.3 X-ray flare would be the one associated with the big loop front (06:50 UT) that quickly surpassed the previous event and then develops as a full halo. In summary, the event has therefore been determined as an asymmetric full halo event, frontsided, associated with an X1.3 X-ray flare on NOAA AR 10792. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050730. 17:14 ENE - Very small brightening just appearing develops as a bright ragged loop front. GOES reported a C8.9 X-ray flare on NOAA AR 10792 (N12E58) between 16:39 - 17:37 UT with peak emission at 17:07 UT. Gusty outflow continues. ---------------------------------------------------------------------------------- 31-Jul-2005: ************ 06:06 SW - Very faint loop front. A small and ragged front a little bit to S can be seen developing later. They fade throughout C3. 06:06 ESE - Elongated and very diffuse front precedes the development of a bright loop front at 06:30 UT. 14:30 E - Diffuse and asymmetric loop front. GOES reported an impulsive M1.1 X-ray flare on NOAA AR 10792 (N13E45) between 12:15 - 12:33 UT with peak emission at 12:24 UT. 20:30 E - Narrow front in the trailing material of previous event. ================================================================================== 01-Aug-2005: ************ 14:30 ENE - Bright loop front. Very faint and diffuse extensions to S. GOES reported an M1.0 X-ray flare on NOAA AR 10792 (N13E32) between 13:00 - 14:29 UT with peak emission at 13:51 UT. ---------------------------------------------------------------------------------- 02-Aug-2005: ************ E - Pseudo-continuous outflow. 13:31 ESE - Elongated and ragged loop front. A very faint and diffuse front develops by the time on E, which is followed at ~ 15:07 UT by an asymmetric loop front. They all fade throughout C3. 15:07 W - Pseudo-continuous outflow. The slow development of a system of faint loops starts to be discernible (though it is difficult to give an exact time of first appearance). By the end of the day it is clearly visible the development (slightly toward WSW) of an expanding and apparently twisted structure. Some infalling material on next day. 18:54 ESE - Bright ragged loop front with twisted core. GOES reported an impulsive M4.2 X-ray flare on NOAA AR 10794 (S13E47) between 18:22 - 18:37 UT with peak emission at 18:31 UT. ---------------------------------------------------------------------------------- 03-Aug-2005: ************ 03:54 ENE - Diffuse and ragged loop front that fades close to the inner edge of C3. 05:30 ESE - Bright and ragged loop front followed by an apparently twisted (and later rather circular) structure. Gusty outflow afterward. GOES reported an impulsive M3.4 X-ray flare on NOAA AR 10794 (S13E45) between 04:54 - 05:11 UT with peak emission at 05:06 UT. 17:54 E - Faint and diffuse ragged loop front in the gust outflow. It fades throughout C3. 23:06 NW - Small and faint ragged blob front that fades throughout C3. ---------------------------------------------------------------------------------- 04-Aug-2005: ************ 00:06 E - Slow (at least at the very beginning) development of a faint loop since late on previous day that later superposes in the LOS with a not-well-defined and diffuse structure. See next event for further details. 01:54 NW - Very elongated and narrow loop front. 06:30 E - The diffuse structure mentioned in previous event develops as an expanding and aparently twisted big structure apparently affecting the development of previous event. It is difficult to precise the time of first appearance, though by 06:30 UT it starts to be rather well discerned. The mean plane-of-sky speed of its LE was ~ 370 km/sec at PA 108, showing an slight acceleration (based on C3 data). GOES reported a C8.4 X-ray flare on NOAA AR 10794 (S15E28) between 05:25 - 06:22 UT with peak emission at 05:59 UT. EIT 195 images show between 05:48 - 09:00 UT a dimming and wave at least 180 deg in extent toward east. **** ICAL01 (Intercalibration for EIT with CDS) **** **** between 10:00 - 11:15 UT. **** **** NO LASCO C2/C3 images during that time. **** 20:30 E - Extremely faint and diffuse front. 23:30 W - Slow development of a system of loop. By the beginning of next day, an elongated an apparently twisted structure can be seen. ---------------------------------------------------------------------------------- 05-Aug-2005: ************ 08:54 NE - Two-component front: i) a diffuse loop front developing toward E, and ii) another one developing as an asymmetric and expanding loop front toward NE, spanning up to past the N Pole. An apparent third front shows up above the N Pole by 09:06 UT becoming then too faint to be followed accurately. Apparently, another one by 11:54 UT. The "complex" event is first seen in C3 at 09:42 UT, above the E - NE limb. Both loop fronts [i) and ii)] are discernible. They develop at apparently the same speed. By 10:42 UT an extremely faint signature can be guessed above the N Pole. Another one by 16:18 UT that develops well past the N Pole up to the NW limb. The mean plane-of-sky speed of the LE of the loop described in ii) at PA 054 was ~ 545 km/sec. GOES reported a long duration C2.6 X-ray flare on NOAA AR 10792 (N14W19) between 06:59 - 08:47 UT with peak emission at 08:05 UT. It was preceded by a B4.3 X-ray flare on NOAA AR 10794 (S14E12), which started at 06:14 UT and finish at 06:34 UT, peaking at 06:23 UT. EIT 195 images show a brightening on AR 10792 by 07:13 UT followed by a dimming (important) and wave toward NE. Inspection of running difference images show another minor brightenings at: i) 08:48 UT on the east side of the AR, and ii) 09:48 UT on its west side. Post flare loops. In summary, the event has therefore been determined as a frontsided event associated with the long duration C-class flare on AR 10792, that showed up in C2 as at least a partial Halo Event. The signal is too faint in C3 in the western hemisphere to establish a clear classification. See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050805. 12:06 NW - Very faint loop front. ---------------------------------------------------------------------------------- 06-Aug-2005: ************ 11:03 E - Very faint and elongated loop front, expanding by 14:38 UT. 12:48 W - Diffuse and ragged loop front developing slightly toward WSW. ---------------------------------------------------------------------------------- 07-Aug-2005: ************ 03:30 NNW - Very faint ragged front. 06:54 ENE - Extremely faint expanding front. Barely discernible in C3. 12:30 NW - Diffuse brightening along streamer precedes the development of a bright loop front (first well seen at 13:31 UT) with apparently twisted inner material. A ragged loop front can be seen at 17:30 UT in the trailing material. GOES reported a long duration C1.4 X-ray flare on NOAA AR 10792 (N08W60) between 11:43 - 14:10 UT with peak emission at 12:49 UT. 15:06 SSE - Very faint jet-like front. ---------------------------------------------------------------------------------- 08-Aug-2005: LASCO C2/C3 and EIT calibrations. ************ WNW - Gusty outflow all along the day. 02:54 W - Jet-like front developing slightly toward WSW. 06:54 SW - Faint, very narrow, and diffuse loop-like front that fades throughout C2. 11:54 W - Very narrow front (jet-like) develops as a bright and narrow loop front (first well seen at 12:30 UT). It fades throughout C3. **** LASCO C2/C3 Data gap between 17:46 - 21:42 UT due to Calibrations. **** ---------------------------------------------------------------------------------- 09-Aug-2005: LASCO C2/C3 and EIT calibrations. ************ 05:54 SW - Very narrow and elongated faint loop front (jet-like). 13:31 SW - Another very narrow and elongated faint loop front (jet-like) to N of previous one. **** NOTE: **** After 16:43 UT and until 00:40 UT on next day, there are **** C2 images only at 17:59, 19:28, and 20:42 UT due to Calibrations. 17:59 W - Diffuse and asymmetric fan-like front already under development. ---------------------------------------------------------------------------------- 10-Aug-2005: LASCO C2/C3 and EIT calibrations. ************ **** No LASCO C3 images between 14:42 - 21:13 UT due to Calibrations. **** 19:31 SSW - Long jet-like front. ---------------------------------------------------------------------------------- 11-Aug-2005: ************ 15:54 SW - Very narrow and elongated fan-like front. It fades very close to the inner edge of C3. 19:31 E - Faint and very diffuse narrow loop front. It fades close to the inner edge of C3. ---------------------------------------------------------------------------------- 12-Aug-2005: ************ 05:30 N - Extremely faint elongated front. 07:54 W - Faint and ragged loop fronts. Difficult to give an exact time of first appearance. **** LASCO C2 Data Gap between 11:30 - 12:54 UT. **** 12:54 E - Curved fan-like front already under development, LE already past the outer edge of C2. First seen in C3 at 12:37 UT. 14:04 WSW - Very faint and narrow (diffuse) loop front (jet-like). 22:30 N - Jet-like front. ---------------------------------------------------------------------------------- 13-Aug-2005: ************ 03:34 WNW - Bright ragged loop front. **** LASCO C2 and C3 Data Gap between 04:30 - 09:06 UT. **** 13:31 W - Bright and elongated loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 14-Aug-2005: ************ 01:31 W - Elongated and diffuse loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 15-Aug-2005: ************ 11:54 N - Diffuse and elongated loop front. It fades throughout C2. 23:06 W - Elongated jet-like front. ---------------------------------------------------------------------------------- 16-Aug-2005: ************ SE - Pseudo continuous outflow along streamer (very faint). 12:30 NNE - Elongated loop front, rather faint. It fades close to the inner edge of C3. 19:54 SE - Extremely faint and not-well-defined front. Difficult to give an exact time of first appearance. It fades throughout C3. ---------------------------------------------------------------------------------- 17-Aug-2005: ************ 07:32 ENE - Small and faint fan-like front followed by some other ragged fronts that fade very close to the inner edge of C3. 07:54 WSW - Faint loop ("V-shaped") front. It fades throughout C3. Another one follows at ~ 13:31 UT a little bit to S. 13:31 ESE - Very faint and not-well-defined front that fades throughout C3. Difficult to give an exact time of first appearance. Some infalling material. 21:08 NE - Jet-like front. ---------------------------------------------------------------------------------- 18-Aug-2005: ************ 16:39 WSW - Brightening just appearing develops as a ragged loop front. It is followed by another one at 18:30 UT. They both fade in C3. ---------------------------------------------------------------------------------- 19-Aug-2005: ************ 12:54 ESE - Ragged loop front that fades close to the inner edge of C3. 16:30 NE - Extremely faint and diffuse front developing toward NNE. It fades throughout C2. 18:06 WSW - Elongated and narrow loop front that fades throughout C2. 19:30 NE - Faint loop front that extends later up to the N Pole. It fades throughout C2. 23:06 NE - Bright and ragged loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 20-Aug-2005: ************ 00:06 N - Faint and rather wide front that seems to coalesce with event at 23:06 UT on previous day. 00:06 NE - Slow development of a system of faint loops. 08:05 NE - Diffuse and expanding (faint) loop front superposed in the LOS with the slow development of the system of faint loops. It fades very close to the inner edge of C3. 10:09 W - A circular front apparently surrounding the C2 occulting disk is first seen on W and above the N Pole. It is first seen in C3 at 14:23 UT above the W Limb. The C3 occulting disk seems to be fully surrounded by around 17:00 UT (though it is difficult to give an exact time due to the faintness of the event on E). 18:57 NE - Bright loop front with circular inner structure and twisted trailing material. Aparently surpassed in the C3 FOV by the following event. 21:30 NE - Asymmetric loop front develops as at least a Partial Halo CME, covering all above the E limb, N Pole, and western limb (brighter on NE). No significant X-ray activity by the time. ---------------------------------------------------------------------------------- 21-Aug-2005: ************ 05:54 W - Faint and diffuse loop front that fades throughout C2. 06:54 N - Jet-like front. 07:31 S - Jet-like front. 07:54 NE - Diffuse and ragged loop front aparently superposed in the LOS with a much fainter and wider expanding front that fades in C3. 09:30 W - Slow development of a system of faint loops. 12:06 W - Faint and diffuse front superposed in the LOS with the system of faint loops. It fades throughout C2. Afterward, the development of the system of loops becomes quicker. 12:54 N - Very narrow loop front (jet-like) developing slightly toward NNE. 16:54 NE - Not-well-defined front that fades throughout C2. 19:31 NNE - Very narrow loop front (jet-like). ---------------------------------------------------------------------------------- 22-Aug-2005: ************ 01:31 W - Bright and ragged loop front (Event #1). Faint extensions develop TWO HALOS above the S Pole by 01:54 UT. By that time, an apparently new front (Event #2), rather diffuse, starts to be seen above the SSE Limb, which fully surrounds the C2 occulting disk by 02:30 UT. The former loop front (i.e., Event #1) develops toward W, and spans at this time (on C2) about 180 deg (from ~ PA 155 - 335). The Event #1 is first seen in C3 above the W Limb at 02:18 UT as a bright loop front surrounded by a faint envelope ahead and also above the S Pole. The Event #2 appears then on SE at 02:42 UT. By 04:42 UT, both events have the occulting disk covered: Event #1 looks like a very asymmetric Full Halo event developing mainly toward W, and Event #2 also like an asymmetric Halo developing mainly toward SE. The mean plane-of-sky speed of Event #1 at PA 235 was ~ 1250 km/sec (outermost edge of the diffuse front ahead of the loop-like structure), while for Event #2 the speed at PA 135 was ~ 580 km/sec. GOES reported an M2.6 X-ray flare from NOAA AR 10798 (S11W54) between 00:44 - 02:18 UT with peak emission at 01:33 UT, most likely associated to Event #1. EIT 195 images show a strong brightening on AR 10798 starting at 01:13 UT. A rather strong intensity disturbance centered on the AR is then seen traveling across the disk. Nice post-flare loops. There are no clear signatures on the disk that could be associated with Event #2. In summary, the complex event apparently consists of the superposition of two likely different asymmetric full Halo events: one frontsided associated to an M2.6 X-ray flare, and another one most probably backsided. See images and movies of the complex event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050822a. 05:30 SW - Very faint and diffuse (fast) loop front. It fades throughout C3. 13:54 NE - Faint and relatively narrow loop front that fades throughout C2. 15:54 E - Ragged loop front. Another one a little bit to N at 16:06 UT. 17:30 W-SW - Huge and bright loop front, the LE almost at the end of the C2 Partial FOV. By 17:54 UT, a circular Halo (faint) seems to start its Halo development in the C2 FOV. It is difficult to establish its & association, if any, with the big loop front event (could it be HALO the shock??). The big loop front is first seen in C3 all above the SW Limb (its footpoints on WNW and past the S Pole) at 17:42 UT. Its mean plane-of-sky speed at PA 232 was 2690 km/sec (pretty fast). By 18:42 UT, the circular front makes its appearance in C3, already surrounding the occulting disk, its mean plane-of-sky speed at PA 125 being ~570 km/sec. By the end of the day, a slight snow storm starts to be seen in LASCO images, becoming rather pronounced during the first hours of next day (a >10 MeV proton event). GOES reported an M5.6 X-ray flare from NOAA AR 10798 (S13W65) between 16:46 - 18:02 UT with peak emission at 17:27 UT. EIT images show a strong and gradual brightening on AR 10798 starting at ~ 17:00 UT and peaking at 17:36 UT. Important dimming and wave centered on the AR. Note that also by 17:00 UT, one can see on ENE the open-up of faint off-limb loops and CME signatures. In summary, at least a Partial Halo Event, frontsided, was detected in association with the M5.6 X-ray flare on AR 10798. But also a rather symmetric full Halo occurred during its development. It is difficult to establish a clear association, if any, with the frontsided event. See images and movies of the complex event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050822b. 17:54 ENE - Elongated loop front that fades close to the inner edge of C3. 22:30 W - Elongated and expanding loop front. 23:30 ENE - Diffuse front along streamer. ---------------------------------------------------------------------------------- 23-Aug-2005: ************ **** LASCO Data gap between 00:00 - 01:42 UT (C2 time) **** 02:30 SW - Faint ragged expanding front. It fades throughout C3. 03:06 E - Bright and ragged loop front developing slightly toward ENE. 06:30 ENE - In the trailing material of previous event, a bright loop front with twisted (rather circular) core develops. Much gusty outflow well into next day. 14:54 WSW - Bright and ragged loop front. Deflection of pre-existent Partial structures. By 17:30 UT, the C2 occulting disk seems to be Halo fully covered, though it is difficult to say whether it is covered by proper features of the event or by features belonging to a different event. The event is first seen in C3 at 15:18 UT, with faint extensions surrounding the main structure, especially to S. Much gusty outflow mainly in the form of ragged and elongated loop fronts all above the W limb follows well into next day. The mean plane-of-sky speed of the outermost part of the diffuse envelope at PA 230 was ~ 2090 km/sec. GOES reported an M2.7 X-ray flare from NOAA AR 10798 (S14W90) between 14:19 - 16:08 UT with peak emission at 14:44 UT. EIT 195 images show a gradual brightening on AR 10798 (just on the limb) starting at 14:24 UT, and peaking at 14:36 UT. An important wave centered on the AR can be seen starting at 14:36 UT (it develops across the visible side of the disk and apparently on the other side, too). Post-flare loops. In summary, the event has been determined as at least a Partial Halo CME associated with a strong limb event (M2.7 X-ray event on NOAA AR 10798). See images and movies of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050823. 21:30 WSW - In the aftermath of previous big event, an elongated loop-like front can be discerned. ---------------------------------------------------------------------------------- 24-Aug-2005: ************ W - Much gusty outflow all along the day. ENE - Much gusty outflow all along the day. 08:30 ENE - Diffuse loop front in the gusty outflow. 16:06 E - Narrow ragged front to S of the gusty outflow. Continuous development. Another clear one at ~ 21:54 UT. ---------------------------------------------------------------------------------- 25-Aug-2005: ************ 04:54 E - Bright and ragged loop front surrounded by faint extensions that extend almost all above the western hemisphere (poles apparently not crossed). GOES reported an M6.4 X-ray flare on NOAA AR 10803 (N09E80) between 04:31 - 04:45 UT with peak emission at 04:40 UT. 10:06 ENE - Elongated loop front in the trail of previous event. It fades throughout C3. 11:30 ENE - Another elongated loop front. 14:06 E - Initially bright and elongated loop front developing slightly toward ENE. **** LASCO Data gap between 14:54 - 16:30 UT (C2 time) **** 16:30 E - Another elongated loop front. 18:54 E - Jet-like front. Another one at 20:58 UT (fainter). ---------------------------------------------------------------------------------- 26-Aug-2005: ************ 00:54 E - Bright and narrow loop front already under development. It fades throughout C3. Another elongated front follows at 02:06 UT. 03:30 ENE - Diffuse brightening just appearing develops as a loop front along the streamer. It fades throughout C2. 06:30 E - Diffuse brightening just appearing develops as a narrow loop front. It fades throughout C2. It is followed by a similar (though smaller) one at 09:06 UT. 08:54 ENE - Loop front developing along the streamer. By 10:06 UT, an apparent distinct front follows. Difficult to distinguish the two fronts in the C3 FOV. An initially much faster event follows later on E (see entry at 12:06 UT). Gusty outflow. 12:06 E - Big and ragged loop front. GOES reported a C2.1 X-ray flare on NOAA AR 10803 (N10E61) between 11:39 - 12:10 UT with peak emission at 11:55 UT. 13:31 ENE - After the initial development of previous two events, the slow development of a faint system of loops can be discerned superposed in the LOS with the trailing material. 17:54 W - Bright ragged loop front with apparently twisted trailing material. Pseudo-continuous outflow follows well into next day on the whole western hemisphere. 21:54 E - Bright and narrow loop front with faint extensions to N. GOES reported a C2.3 X-ray flare on NOAA AR 10803 (N10E49) between 21:52 - 22:08 UT with peak emission at 22:02 UT. A similar front follows at 00:06 UT on next day. Pseudo-continuous outflow all along the day and well into next day. ---------------------------------------------------------------------------------- 27-Aug-2005: ************ 00:06 E - Bright and narrow loop front with faint extensions to N. 03:54 ENE - Bright ragged blob-like front in the pseudo-continuous outflow. 05:30 E - Another bright and narrow loop front with faint extensions to N. By 06:54 UT, a bright feature develops, fading by the end of the C2 FOV. 10:56 SW - Not-well-defined and very diffuse (faint) front. Difficult to give an exact time of first appearance. 11:54 E - Narrow and ragged loop-like feature that fades very close to the inner edge of C3. 17:30 ENE - Ragged and elongated loop front develops toward E. It fades throughout C3. 21:30 E - Very narrow loop front (jet-like). 23:06 ENE - Blob-like feature along streamer. ---------------------------------------------------------------------------------- 28-Aug-2005: ************ 01:31 W - Elongated feature precedes big event. See entry at 02:30 UT. 02:30 W - Big and bright loop front. It is first seen in C3 at 03:18 UT. 03:54 E - Very faint and diffuse elongated loop front. 06:06 ENE - Elongated feature preceding an asymmetric loop front (brighter to S) that is first seen at 06:54 UT. 10:56 E - Bright and big ragged loop front with faint extensions to S. First seen in C3 at 11:18 UT. Development missed in the following data gap. GOES recorded an M1.6 X-ray flare on NOAA AR 10803 (N09E36) between 10:17 - 10:27 UT with peak emission at 10:28 UT. **** LASCO Data Gap between 12:06 - 23:30 UT (C2 time). **** ---------------------------------------------------------------------------------- 29-Aug-2005: ************ 01:54 W - Faint and elongated loop front. 05:30 E - Very faint and not-well-defined front leading the development of an apparently twisted structure. 07:31 WSW - Faint and diffuse feature. 10:54 W - Loop front just appearing develops as a wide and bright expanding HALO loop front. Faint extension are seen to S by 11:06 UT. By 11:30 UT, the extensions fully surround the C2 occulting disk. By that time, the LE of the event on West is already past the outer edge of the C2 FOV. The event is first seen in C3 at 11:18 UT above the WSW-W Limb, the occulting disk being covered by 11:42 UT by the faint extensions. The bulk of the CME (i.e., the loop-like structure) develops (projected in the plane of the sky) mainly toward W. The mean plane-of-sky speed of the LE (outermost front) of the event at PA 231 was ~ 1540 km/sec. GOES reported no significant X-ray activity by the time of the event. Likewise, EIT 195 running difference images do not show significant activity on the disk. However, they do show signatures of a huge backsided CME starting at 11:00 UT above the SW. By 11:12 UT, the intensity disturbance (i.e., the CME signature) covers all above the SW, W, and NW limb. In summary, the event has therefore been determined as an asymmetric Full Halo Event, backsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050829 13:31 SW - Following the halo event some ragged loop fronts develop. In particular at: 13:31, 14:06, and 18:06 UT. Gusty outflow into next day. 23:30 E - Bright ragged loop front followed by an apparently twisted structure. ---------------------------------------------------------------------------------- 30-Aug-2005: ************ 03:54 WSW - Faint loop front a little bit to N of the gusty outflow. 09:06 NNE - Faint jet-ike front. 19:31 E - Faint and ragged blob-like front. ---------------------------------------------------------------------------------- 31-Aug-2005: KEYHOLE ************ 07:31 NE - Very faint expanding loop front mainly developing toward NE, first seen as a very faint and diffuse front. By 09:06 UT, the angular span of the front in C2 seems to cover from the ESE Limb up up NW Limb (clockwise), though in NW is too faint to define its edge. It is first seen in C3 above the NE Limb at 08:42 UT. The main plane-of-sky speed of the event at PA 35 was about 385 km/sec (last frame used: 10:42 UT; LE at ~ 9 solar radii). GOES reported no significant activity by the time prior to the LASCO event. On the other hand, EIT 195 images show a small ejection starting at 06:12 UT, on the southern hemisphere close to the central meridian (far west of AR 10806), just on the border of the southern coronal hole, developing toward SE (see next entry). See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050831 07:31 SE - Diffuse and rather elongated front. 10:06 NE - Another diffuse front (a little brighter than the one at 07:31 UT on NE). By 11:30 UT, the event seems to span in C2 from ESE well up to the NW limb (clockwise). It is first clearly seen in C3 above the NE Limb at 10:42 UT. This event seem to coalesce with the one at 07:31 UT on NE in the C3 FOV by 12:18 UT (at about 11 solar radii), either because the second event is faster or the first one becomes too faint to be distinguished. The mean plane-of sky speed of the event at PA 40 was ~ 445 km/sec (last frame used: 13:42 UT; LE at ~ 12.5 solar radii). GOES reported no significant activity by the time prior to the LASCO event, except for a B3.2 X-ray flare on NOAA AR 10806 (S17E32) between 09:52 - 10:08 UT with peak emission at 10:02 UT. EIT 195 images show a dimming region just on SE of AR 10806 starting at 10:00 UT, i.e., during the time of the B3.2 X-ray flare. Based on the global appearance on C3 of the events reported to start at 07:30 UT and the present one, the complex event could be classified as a faint and complex Partial (at least) Halo Event. Though the timing of the EIT events reported seem to correlate with the respective LASCO events, the corresponding spatial location on the disk doesn't. Therefore, it is hard to be sure about the location of their source. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050831 11:30 W - Small brightening just appearing above the W Limb develops as a HALO bright loop front. It is followed (apparently about one hour later) by a fainter and diffuse expanding loop front with faint extensions on E. The C2 occulting disk appears fully covered by 13:31 UT. The "halo" looks rather flat over the poles, and elongated toward W and E. The event is first seen in C3 above the W Limb at 12:42 UT. The C3 occulting disk seems to be fully surrounded by 12:42 UT. The event fades throughout C3. The mean plane-of-sky speed of the outermost edge of the event on W (PA 285) was ~ 860 km/sec. GOES reported a long duration C2.0 X-ray flare on NOAA AR 10803 (N13W13) between 10:26 - 12:51 UT with peak emission at 11:51 UT. EIT 195 images show a brightening on AR 10803 starting at 10:36 UT all along the magnetic inversion line (extending E-W) followed by a dimming region mainly to W and NW of the AR. Post flare loops. In summary, the event has therefore been determined as a faint Full Halo Event, frontsided, associated to a C-class X-ray event on NOAA AR 10803. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050831 17:54 WNW - Couple of small ragged fronts. 18:54 ESE - Kind of reconection event (blob-like front going out and another falling down). 22:30 HALO - The event appears as a very bright and thick loop front extending all the way from the E limb to the W limb passing over the S Pole with diffuse (though rather bright) extensions ahead (mainly toward S). The thick loop front seems to close the circle around the occulter (all the the way above the N Pole), though not as bright. By 23:06 UT, the event appears brightest on SE. A new expanding loop front follows at 00:54 UT on next day on SE. Another one at 03:06 UT on SSE. The event is first seen in C3 at 23:18 UT, already fully surrounding the occulting disk, the LE of the outermost part of the event on S (diffuse front ahead of the thick loop-like structure) being at 13 solar radii. The mean plane-of sky speed of the LE of several features at various PA is given below: - PA 180: 1870 km/sec (LE of the diffuse front ahead of the loop- like structure, i.e., that of the shock) - PA 180: 1270 km/sec (LE of the loop-like structure) - PA 270: 1225 km/sec (LE of the loop-like structure) - PA 356: 745 km/sec (LE of the loop-like structure) - PA 050: 685 km/sec (LE of the loop-like structure) showing practically no acceleration in all cases. GOES reported no significant X-ray activity by the time of the event. Likewise, EIT 195 running difference images do not show significant activity on the disk by the time prior to the LASCO event. However, they do show signatures of a huge backsided CME all above the S limb starting at 22:24 UT. By 22:36 UT, the CME signature can be seen almost above all around the limb. In summary, the event has therefore been determined as a symmetric and very strong Full Halo Event, backsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050831b ================================================================================== 01-Sep-2005: KEYHOLE ************ 00:54 SE - Couple of ragged and expanding loop fronts develop in the aftermath of the halo CME reported to start at 22:30 UT on previous day. 02:54 SSE - Ragged and expanding loop front followed at 05:30 UT by another one. 11:30 W - Diffuse brightening all above the W Limb (brighter on SW). By 12:06 UT, a wide loop front spanning initially from NW up to the S Pole (clockwise) develops behind the diffuse front. Pre-existent features on S - SE are apparently disturbed by the development of this wide loop front, and hence giving to the event in C2 the appearance of a Halo CME. The complex event fades throughout C3. EIT 195 running difference images show faint rising loops off limb on W - WSW (source on the backside) between 10:24 - 12:00 UT. GOES reported no significant X-ray activity (A-class) by the time. 12:06 WSW - Loop front along streamer with apparently twisted inner structure is followed at 13:31 UT by a ragged loop front. The trailing (twisted) material of both events superposes in the LOS and therefore becomes difficult to distinguish between both events. No clear signatures of both events can be distinguished in EIT 195 images. GOES reported no significant X-ray activity (A-class) by the time. 18:54 ESE - Diffuse brightening along streamer that fades in C2. 20:06 WSW - A system of faint expanding loops develops in the trailing material of the "complex" event reported to start at 12:06 UT. 23:54 ESE - Diffuse loop front quickly overpassed by big event on NE - E at 00:30 UT on next day (Event #1, seen Event at 00:30 UT on next day). ---------------------------------------------------------------------------------- 02-Sep-2005: KEYHOLE ************ 00:30 NE - Big and bright feature with its LE close to the end of the C2 Complex FOV all above the NE limb (Event #2). A brighter front can be HALO seen also by 00:30 UT on W (Event #3), in the inner part of Event Event #2 (as projected in the plane of sky). Upon inspection of the C2 movie, one can see that Event #1 is quickly surpassed by Event #2 and therefore no longer discernible. By 00:54 UT, Event #2 seems to fully surround the C2 occulting disk (though very faint on S). Event #3 develops toward E, followed at 01:31 UT by another ragged front on SE (Event #4, though it is difficult to say whether it is really a different feature). Event #2 is first seen in C3 at 00:42 UT all above the NE Limb. Signatures of Event #3 are first seen on E at 01:42 UT, followed at 02:18 UT on SE by Event #4. Considered as a whole, the complex event covers the C3 occulting disk by 01:42 UT (on W still barely above the limb), becoming difficult to disentangle the different components. The mean plane-of sky speed of the LE of different features is given below: - Event #2: PA 63 --> ~ 1450 km/sec - Event #3: PA 100 --> ~ 670 km/sec - Event #4: PA 150 --> ~ 660 km/sec GOES reported a B4.5 X-ray flare from NOAA AR 10806 (S17E12) on 2005/09/01 between 22:53 - 23:56 UT with peak emission at 23:21 UT. EIT 195 images show the development of a dimming region starting between 22:36 - 23:12 UT (on 09/01) to N, E, and S of AR 10806. Running difference 195 images show signatures of a CME developing by the time mainly toward SE and E (these signatures are most likely related to Events #3 and #4). By 00:24 UT, signature of a huge and apparently backsided CME can be seen all above the E Limb (most likely related to Event #2). Though the timing seems to match that of the event from AR 10806, the event off limb is most probably from the back side of the Sun. In summary, the event as a whole can be determined as an asymmetric full halo CME. Several components contribute to the overall shape of the complex event, at least one of them frontsided, which was associated with a B-class X-ray flare on NOAA AR 10806. However, the bigger contribution seems to have its origins on the backside. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050902 03:30 W - Ragged loop front. 06:30 E - Faint and asymmetric loop front in the aftermath of the halo CME. 11:30 W - Loop front developing along streamer. Twisted trailing material. 12:30 NNE - Diffuse front that quickly fades. 16:06 WSW - Ragged blob-like front. 17:30 SE - Diffuse loop-like front that fades throughout C3. **** EIT CCD bakeout between Sep 2 23:00 UT - Sept 23 10:00 UT **** **** Mini-cal pre and post sets as follows: **** **** 2005/09/02 19:00 - 2005/09/03 01:00 **** **** 2005/09/23 20:00 - 2005/09/24 00:20 **** **** ==> NO EIT images between 09/02 19:00 - 09/24 00:20 UT. **** 20:54 SE Diffuse and expanding loop-like front. It also fades throughout C3. ---------------------------------------------------------------------------------- 03-Sep-2005: KEYHOLE ************ 03:12 SE - Bright loop front. Very tenuous and diffuse extensions can be Asymmetric then seen around the main loop-like structure. Faint extensions Halo fully cover the C2 occulting disk by 04:12 UT. The event is first seen in C3 at 03:42 UT as a bright loop front above the SE limb with faint and diffuse extensions to S. Following frames show the loop-like structure surrounded by a diffuse and faint envelope (shock?). This diffuse envelope fully surrounds the C3 occulting disk by 05:18 UT (LE at ~ 20 solar radii on SE, while barely above the limb on NW). The mean plane-of-sky speed of the LE of the outermost part of the diffuse front ahead of the main loop-like structure (shock) at PA 150 was ~ 1680 km/sec, while that of the LE of the bright loop-like structure at PA 145 was ~ 1390 km/sec. GOES reported no significant X-ray activity (A-class) during the day, save for an impulsive B6.1 X-ray flare from NOAA AR 10805 (S11W09) between 04:05 - 04:13 UT with peak emission at 04:10 UT. No EIT images are available (last EIT 195 image available: 19:13 UT, afterward EIT CCD bakeout. The event's shape and development seem to suggest that the old NOAA AR 10798, which is due to return on 09/07, would have likely been associated with the observed Halo. In summary, the event has therefore been determined as an asymmetric Full Halo Event, probably backsided (based on the lack of X-ray activity reported by GOES and the spatial matching of its likely origin with that of old AR 10798). See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050903 12:24 E - Faint ragged loop front. 20:48 E - Small and elongated front. ---------------------------------------------------------------------------------- 04-Sep-2005: KEYHOLE ************ 09:48 ENE - Faint front that quickly fades. 12:24 NE - Gradual development of a ragged front along streamer (difficult to give an exact time of first appearance) followed at 13:24 UT by a faint system of loops that quickly vanishes. 14:48 NE - In the trailing material of previous event, a bright loop, top of an elongated twsited structure follows. 14:48 NW - Bright loop front with core and twisted trailing material. Very faint extensions to N and S. Small and fast front at 18:00 UT in the trailing material. Gusty outflow afterward in the form of small ragged fronts along a current sheet, well into next day. GOES reported a long duration C2.0 X-ray flare from NOAA AR 10803 (N13W72) between 14:08 - 16:21 UT with peak emission at 15:06 UT. 22:36 E - Elongated and initially bright loop front. It fades throughout C3. Some infalling material. ---------------------------------------------------------------------------------- 05-Sep-2005: KEYHOLE ************ 09:48 SE - Bright loop front. Diffuse extensions can be then seen around Asymmetric the bright loop-like structure. By 10:12 UT, (LE just past the Halo end of the C2 FOV), the total angular span of the event -diffuse extensions included- is about 240 deg (from PA 25 - 265). By 10:36 UT, the C2 occulting disk appears fully covered, though the faint feature surrounding the occulting disk seems to be other [1] than the faint and diffuse extensions. The event is first seen in C3 at 10:18 UT above the SE Limb. Following frames show the loop-like structure surrounded by a diffuse and faint envelope (shock?). "Apparently", the diffuse envelope do not reach to fully cover the occulting disk (though it is hard to say due to the superposition with [1]); by 11:42 UT, it spans from PA 10 - 300 (~ 290 deg). By 11:42 UT, the circular feature reported to surround the C2 occulting disk at 10:36 UT (i.e., [1]), seems to cover the C3 occulting disk, apparently developing (as projected in the plane-of sky) slightly toward NW. The mean plane-of-sky speed of the LE of the outermost part of the diffuse front ahead of the main loop-like structure (shock) at PA 148 was ~ 2220 km/sec, while that of the LE of the bright loop-like structure at PA 143 was ~ 1895 km/sec, showing in both cases practically no acceleration. GOES reported a long duration C2.7 X-ray flare on S07E81 between 08:53 - 12:20 UT with peak emission at 10:41 UT. No EIT images are available (last EIT 195 image available: 2005/09/02 @ 19:13 UT, afterward EIT CCD bakeout ** 2005/09/02 23:00 UT - 2005/09/23 10:00 UT **). The event's shape and development seem to suggest that the old NOAA AR 10798, which is barely behind the SE Limb, was likely associated with the observed Halo. In summary, the event has therefore been determined as a very fast limb event, most likely associated to the old AR 10798, just behind the SE limb. Its associated shock made it appear in the LASCO FOV as a very asymmetric Full Halo Event. Given the lack of EIT images, it is not clear at this stage the relation of the rather circular structure reported to surround the C2 occulting disk at 10:36 UT with the limb event. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050905 ---------------------------------------------------------------------------------- 06-Sep-2005: KEYHOLE ************ 03:36 NW - Diffuse and very faint ragged loop front. It fades throughout C3. 08:12 SE - Diffuse and ragged front, apparently the top of a diffuse and twisted structure that expands toward N. 20:00 SE - Bright loop front develops as an asymmetric and expanding bright loop front mainly toward E. GOES recorded a long duration M1.4 X-ray flare on S12E88 (AR barely behind the limb) between 09/06 19:32 - 09/07 00:44 UT with peak emission at 22:02 UT. 21:12 WNW - Gradual brightening of the cusp of the streamer preceding the development of a bright loop front followed by a cavity and apparently twisted inner core (prominence material). Typical 3-part structure CME. ---------------------------------------------------------------------------------- 07-Sep-2005: KEYHOLE ************ 01:00 WSW - Faint ragged loop fronts partly superposed in the LOS with the trailing material of previous event. Twisted structure slowly developing. 06:00 SE - Ragged blob-like fronts along streamer. Faint arcades apparently connecting to NE. **** LASCO CLOSES doors at 11:00 UT in preparation for **** **** S/C roll, MM, and SK on 2005/09/08. **** **** Note: MONSTER X-RAY FLARE **** GOES recorded an X17 X-ray flare on NOAA AR 10808 (old 10798) between **** 17:17 - 18:03 UT with peak emission at 17:40 UT (S11E77). ---------------------------------------------------------------------------------- 08-Sep-2005: KEYHOLE = NO LASCO IMAGES = ************ **** LASCO doors CLOSED (S/C Maneuvers: 180 deg roll, SK, and MM). **** **** Note: HIGH X-RAY ACTIVITY **** Following the X17 X-ray Event on 09/07 from NOAA AR 10808 (peak at 17:40 UT) **** GOES recorded on 09/08 multiple C-class X-ray activity in addition to the **** following X-ray flares (all from AR 10808): **** - an M2.1 (S12E74) between 16:49 - 17:11 UT (peak at 17:03 UT), **** - another M2.1 (S12E70) between 20:23 - 20:49 UT (peak at 20:41 UT), and **** - an X5.4 X-ray flare (S12E75) between 20:52 - 21:17 UT (peak at 21:06 UT). ---------------------------------------------------------------------------------- 09-Sep-2005: KEYHOLE ************ **** LASCO doors OPEN at 12:00 UT after S/C Maneuvers on 09/08. **** **** NOTE: **** First C2 image available taken at 12:21 UT. The images look highly **** degraded by the ongoing proton storm initiated after the X17 X-ray **** flare from NOAA AR 10808 (old 10798) on Wed Sep 7, and apparently **** intensified by the high X-ray and CME associated activity that **** followed afterward. Some faint events maybe missing. 19:48 ESE - Bright an asymmetric loop front on the ESE Limb. Next frames Asymmetric show the main loop structure surrounded by a faint and diffuse Halo envelope. This diffuse envelope seems to fully cover the C2 occulting disk by 20:12 UT (LE on SE already past the end of the C2 FOV). Much gusty outflow on SE afterwards. The event is first seen in C3 at 20:18 UT spanning all the way from the NE limb up to past the S Pole (counterclockwise). By 20:42 UT, the C3 occulting disk is fully surrounded. The mean plane-of- sky speed of the outermost front at PA 100 was ~ 2300 km/sec. On Fri Sep 9, multiple C-class activity continues plus the following X-ray flares (all from NOAA AR 10808): - an M1.0 (S13E68) between 02:08 - 02:29 UT (peak at 02:19 UT), - an M1.1 (S12E68) between 02:33 - 02:39 UT (peak at 02:36 UT), - an X1.1 (S12E68) between 02:43 - 03:07 UT (peak at 03:00 UT), - an M1.8 (S10E67) between 04:46 - 05:12 UT (peak at 05:03 UT), - an M6.2 (S13E71) between 05:32 - 06:00 UT (peak at 05:48 UT), - an X3.6 (S11E66) between 09:42 - 10:08 UT (peak at 09:59 UT). Unfortunately, there were no LASCO images up to noon UT. Therefore, we can say nothing about the potential CME events associated with those X-ray events. Later in the day (Sep 9) GOES recorded: - an M1.9 (S11E60) between 17:32 - 18:10 UT (peak at 17:51 UT), - an X6.2 (S12E67) between 19:13 - 20:36 UT (peak at 20:04 UT). The latter is the X-ray event most likely associated to the event observed by LASCO. Due to the EIT CCD bakeout, there were no EIT images. In summary, the event has therefore been determined as an asymmetric Full Halo Event, frontsided, associated to an X6.2 X-ray flare from AR 10808. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050909 ---------------------------------------------------------------------------------- 10-Sep-2005: KEYHOLE ************ **** LASCO images still look highly degraded by the ongoing **** **** proton storm. Some faint events maybe missing. **** 07:17 SE - Elongated loop front. GOES recorded an M3.7 X-ray flare on NOAA AR 10808 (S11E51) between 06:06 - 06:17 UT with peak emission at 06:14 UT. 21:52 SE - Bright and asymmetric loop front on the SE Limb. Next frames Asymmetric show the main loop structure surrounded by a faint and diffuse Halo envelope. This diffuse envelope seems to fully cover the C2 occulting disk by 22:07 UT (LE on ESE already past the end of the C2 FOV). Pseudo-continuous outflow on SE afterward, moving toward the SSE limb. The event is first seen in C3 at 22:15 UT spanning all the way from the NE limb up to past the S Pole (counterclockwise). By 23:41 UT, the C3 occulting disk is fully surrounded. The mean plane-of-sky speed of the outermost front at PA 115 was ~ 1750 km/sec (take into account that the proton storm plus the faintness of the outermost front contribute to certain uncertainty in the speed determination). On Sat Sep 10, multiple C-class activity continues. On top of that, the following X-ray flares (all from NOAA AR 10808) were recorded by GOES: - an M3.7 (S11E51) between 06:06 - 06:17 UT (peak at 06:14 UT), - an M1.9 (S12E51) between 08:59 - 09:31 UT (peak at 09:07 UT), - an X1.1 (S11E47) between 16:34 - 16:51 UT (peak at 16:43 UT), - an M4.1 (S12E45) between 19:10 - 19:50 UT (peak at 19:36 UT), - an X2.1 (S13E47) between 21:30 - 22:43 UT (peak at 22:11 UT). The latter is the X-ray event most likely associated to the event observed by LASCO. Due to the EIT CCD bakeout, there were no EIT images. In summary, the event has therefore been determined as an asymmetric Full Halo Event, frontsided, associated to an X2.1 X-ray flare from AR 10808. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050910 ---------------------------------------------------------------------------------- 11-Sep-2005: KEYHOLE ************ **** LASCO images still look highly degraded by the ongoing **** **** proton storm, though not as much as before. The proton **** **** storm seems to be slowly decaying. **** 13:00 ESE - Bright loop front just appearing above the ESE Limb. It develops Asymmetric as a bright and wide loop front toward SE with some faint and Halo diffuse extensions that make the whole event appear wider. By 13:48 UT, the whole event spans in C2 ~ 240 deg (from PA 20 to 260). The signal is too faint on NW to be certain whether the event reaches to fully cover the C2 occulting disk. Gusty outflow on SE afterward. The event is first seen in C3 at 13:36 UT all above the SE Limb. By 14:42 UT, the C3 occulting disk seems to be fully covered, on NW by very faint and diffuse extensions. The mean plane-of-sky speed of the outermost front at PA 110 was about 1960 km/sec (based on C3 data). On Sat Sep 11, GOES continued recording multiple C-class X-ray activity from NOAA AR 10808. It also recorded on the same AR an M3.0 X-ray flare (S16E39) between 12:44 - 13:53 UT with peak emission at 13:12 UT. The M flare is the X-ray event most likely associated to the event observed by LASCO. Due to the EIT CCD bakeout, there were no EIT images. In summary, the event has therefore been determined as an asymmetric Full Halo Event, frontsided, associated to an M3.0 X-ray flare from AR 10808. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050911 20:57 SE - In the aftermath of previous Halo, a diffuse and ragged loop front can be discerned. GOES recorded an impulsive M1.3 X-ray flare on NOAA AR 10808 between 20:29 - 20:49 UT with peak emission at 20:40 UT. ---------------------------------------------------------------------------------- 12-Sep-2005: KEYHOLE ************ **** Proton storm finally subsiding by the end of the day. **** **** Multiple C-class X-ray flares on NOAA AR 10808. **** SE - Some gusty outflow all along the day. 07:00 SE - In the gusty outflow, a faint ragged loop front can be discerned. GOES recorded an impulsive M1.3 X-ray flare on NOAA AR 10808 (S11E33) between 06:56 - 07:05 UT with peak emission at 07:01 UT. 09:24 SE - Ragged loop front a little bit to N of previous event. GOES recorded an M6.1 X-ray flare on NOAA AR 10808 (S11E25) between 08:37 - 09:20 UT with peak emission at 09:03 UT. 20:24 E - Very faint loop front that quickly fades. ---------------------------------------------------------------------------------- 13-Sep-2005: KEYHOLE ************ 13:12 NE - Faint and asymetric loop front. 20:00 SE - Bright loop front all above the SE Limb, preceded by a faint Asymmetric and diffuse envelope. By 20:12 UT, faint extensions are seen all Halo around the main loop structure; a second ragged front seems to come behind the first loop front. The C2 occulting disk is fully surrounded by 20:36 UT by the diffuse extensions, the LE on SE being already past the end of the C2 FOV. By this time, the existence of apparently two consecutive fronts becomes clearer. Much gusty outflow follows on the S Pole. There is a C2 data gap between 23:36 - 03:24 UT due to a telemetry data gap (not recovered yet). The event is first seen in C3 at 20:18 UT all above the SE Limb. The C3 occulting disk is fully covered by 21:18 UT (signal on NW just above the limb, while on SE the LE is already at 16 solar radii). The mean plane-of-sky speed of the outermost front of the diffuse envelope at PA 145 was ~ 1865 km/sec, while the speed of the LE of the bright loop-like structure at PA 151 was 1680 km/sec. GOES recorded a long- duration X-ray event on NOAA AR 10808. First, a complex (two peaks) X-ray flare (on about S09E10) between 19:19 - 20:57 UT with peak emission at 19:27 UT (X1.5) and 20:04 UT (X1.4). And then, an X1.7 X-ray flare (on about S10E03) between 23:15 - 23:30 UT with peak emission at 23:22 UT. Due to the EIT CCD bakeout, there were no EIT images. In summary, the event has therefore been determined as a strong and complex asymmetric Full Halo Event, frontsided, associated to the first part of a triple X-ray flare from NOAA AR 10808. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20050913 ---------------------------------------------------------------------------------- 14-Sep-2005: KEYHOLE ************ **** NOTE: **** There is a slight increase of energetic particle hits (after the complex **** X-ray class event of yesterday and associated Halo CME). S - Much gusty outflow all along the day moving toward SSW. Among multiple C-class X-ray flares on NOAA AR 10808, GOES recorded an M4.6 X-ray flare between 10:05 - 10:54 UT with peak emission at 10:38 UT. 14:48 NE - Faint and elongated loop front that fades close to the inner edge of C3. 20:57 W - Very faint front developing slightly toward WNW. ---------------------------------------------------------------------------------- 15-Sep-2005: KEYHOLE ************ SSW - Much Gusty outflow all along the day moving toward SW. Among multiple C-Class X- ray flares GOES recorded the following X-ray flares (all activity from NOAA AR10808): - an X1.1 (S12W14) between 08:30 - 08:46 UT (peak at 08:38 UT), - an M1.0 (S11W19) between 18:55 - 19:26 UT (peak at 19:10 UT). **** LASCO doors closed (No LASCO images) between **** **** 13:00 - 16:00 UT because of CDS recovery. **** ---------------------------------------------------------------------------------- 16-Sep-2005: KEYHOLE ************ 06:48 NE - Faint jet-like front. 09:36 SW - Ragged blob-like front along the streamer. Another one on W. Some few more along the day. 14:36 E - Brightening just appearing develops as a ragged loop front, slightly toward ESE. It fades very close to the inner edge of C3. ---------------------------------------------------------------------------------- 17-Sep-2005: KEYHOLE ************ 08:48 E - "Pair formation" at about 5 solar radii, PA 75 (one blob coming out and another one falling down). 14:48 E - Extremely faint and ragged front developing slightly toward ESE. It fades throughout C2. 17:12 NNW - Faint jet-like front. ---------------------------------------------------------------------------------- 18-Sep-2005: KEYHOLE ************ 05:00 E - Ragged loop front that fades close to the inner edge of C3. 10:24 ESE - Diffuse loop front developing toward ESE. It fades throughout C3 (very faint). 21:36 NW - Faint loop front that quickly fades. ---------------------------------------------------------------------------------- 19-Sep-2005: KEYHOLE ************ 15:12 SE - Faint and ragged loop front. 22:12 E - Faint fan-like front that fades throughout C2. It is followed at 23:48 UT by an elongated loop front. ---------------------------------------------------------------------------------- 20-Sep-2005: KEYHOLE ************ ENE - Since late on previous day, the very slow development of a system of very faint loops along the streamer can be discerned. The event starts to be seen in C3 at around 06:18 UT developing as a faint loop-like front. By 13:18 UT (C3 time), an apparently different front moving faster develops behind. 19:12 E - Elongated loop front, first seen in C3 at 20:18 UT. ---------------------------------------------------------------------------------- 21-Sep-2005: KEYHOLE ************ E - Pseudo-continuous outflow all along the day. 19:00 E - Slow development of a loop front (helmet-like). By 21:24 UT, a slighty brighter loop front follows. Some faint trailing material. ---------------------------------------------------------------------------------- 22-Sep-2005: KEYHOLE ************ 18:24 E - Very faint and diffuse front that fades throughout C2. 19:36 E - Elongated and asymmetric loop front a little bit to S of previous event, apparently the top of a big twisted structure. ---------------------------------------------------------------------------------- 23-Sep-2005: KEYHOLE ************ 00:12 E - A bright loop front followed by a cavity and twisted inner core develops in the trailing material of the event reported to start at 19:36 UT on previous day. Gusty outflow. 06:24 SSW - Extremely faint loop front. Barely visible in C3. 14:12 SSW - Slow development of a very faint and expanding loop front. It fades throughout C3. **** LASCO Data Gap beteen 20:57 - 23:34 UT (C2 times). **** 23:34 ESE - Elongated loop front already under development after data gap. It fades throughout C3. ---------------------------------------------------------------------------------- 24-Sep-2005: KEYHOLE ************ 15:54 NE - Diffuse brightening top of an apparently twisted structure. It is followed at 16:54 UT a little bit to N by a diffuse loop front that spans up to the N Pole. They all fade throughout C3. ---------------------------------------------------------------------------------- 25-Sep-2005: KEYHOLE ************ 02:06 E - Elongated loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 26-Sep-2005: KEYHOLE ************ 19:31 W - Narrow and elongated loop front. Development partly missed in the followinf data gap. **** LASCO Data Gap between 20:54 - 24:00 UT (C2 times). **** ---------------------------------------------------------------------------------- 27-Sep-2005: KEYHOLE ************ **** LASCO Data Gap between 00:00 - 01:43 UT (C2 times). **** 05:54 SW - Slow development of a system of faint (and relatively narrow) loops along the streamer. Difficult to give an exact time of first appearance. ---------------------------------------------------------------------------------- 28-Sep-2005: END OF KEYHOLE ************ 01:54 ESE - Initially diffuse front develops as a big and asymmetric bright loop front (apparently a complex two-component front). By 04:54 UT the whole event spans from the N Pole up to the S Pole (on the eastern hemisphere). Pseudo-continuous outflow all across the eastern hemisphere and some faint expanding loop fronts on S afterward and continuing all along the day. EIT 195 images do not show signatures of a frontsided (nor limb) event prior to the time of first appearance in C2. 06:54 E - Bright and elongated front in the aftermath of previous event. 11:30 SW - Narrow an elongated loop-like structure. 17:29 SW - Very faint and elongated loop front. 18:13 ENE - Bright loop front preceded by a faint and diffuse front. Extremely faint expanding extensions up to SE. 19:43 SE - Faint and elongated loop front. ---------------------------------------------------------------------------------- 29-Sep-2005: ************ 04:54 E - Faint and elongated loop front. It fades very close to the inner edge of C3. 05:30 SW - Blob-like front. It fades throughout C3. 08:30 WNW - Faint ragged loop front brighter to N that fades close to the inner edge of C3. ---------------------------------------------------------------------------------- 30-Sep-2005: ************ **** Infalling material on E all along the day. **** Otherwise, no significant activity. ================================================================================== 01-Oct-2005: ************ 05:30 E - Blob-like front developing slightly toward ESE. Infalling material continues all along the day. ---------------------------------------------------------------------------------- 02-Oct-2005: ************ 00:30 N - Very faint elongated and expanding loop front. Difficult to give an exact time of first appearance. A similar front seems to precede this event (too faint). 00:30 SE - Slow development of several loop fronts. 05:30 E - Elongated and initially bright loop front. More infalling material. 15:30 NW - Large jet-like front. 18:54 S - Diffuse jet-like front. 19:31 W - Not-well-defined front along streamer that fades throughout C2. Some gusty outflow well into next day. 21:54 SW - Narrow loop front that fades throughout C2. 23:06 E - Ragged loop front. ---------------------------------------------------------------------------------- 03-Oct-2005: ************ E - Infalling material all along the day. 00:54 S - Jet-like front. 06:30 S - Faint and very narrow loop front (jet-like) that fades throughout C2. 14:30 E - Faint blob-like front starts to be discernible. 17:06 S - Faint and very narrow loop front that fades throughout C2. 19:54 WNW - Bright loop front with core. Twisted trailing material. EIT images show filament eruption on NW starting slightly before 19:26 UT (until ~ 20:24 UT). ---------------------------------------------------------------------------------- 04-Oct-2005: ************ 00:06 WNW - In the trailing material of event at 19:54 UT on previous day, a small and narrow bright front develops, apparently with corresponding material coming down, well seen at 00:54 UT ("pair formation"). 05:54 SE - Brightening just appearing develops as a typical three-part structure CME (bright LE, cavity, and core). EIT images show a filament eruption starting at 04:12 UT from AR just coming around the SE Limb. By 07:54 UT, an apparently new front can be discerned at roughly the PA of the northern leg. Twisted trailing material. 09:06 E - Ragged (and relatively narrow) loop front. 18:26 SSE - Small front that quickly fades. ---------------------------------------------------------------------------------- 05-Oct-2005: ************ 00:50 N - Faint and diffuse jet-like front. 02:06 NE - Extremely faint and not-well-defined front that quickly fades. 07:50 SSE - Diffuse and ragged front. It fades throughout C3. 08:26 WNW Faint and elongated loop front. Difficult to give a precise time of first appearance. 12:06 NE - Another extremely faint and not-well-defined front that quickly fades. 12:26 SSW - Extremely faint loop-like front. Barely visible in C3. ---------------------------------------------------------------------------------- 06-Oct-2005: ************ 00:26 SE - Couple of blob-like fronts. 08:50 WSW - Difusse and slightly asymmetric (brighter to S) loop front. It fades throughout C3. 10:06 N - Faint and diffuse jet-like front developing slightly toward NNE. 12:06 NNE - Another faint jet-like front. 14:26 E - Diffuse brightening. By 15:05 UT, a faint and ragged asymmetric front can be seen developing all above the SE Limb. Barely visible in C3. Also by 15:06 UT, an apparently distinct loop- like front can be discerned above the S Pole (fading then throughout C2). ---------------------------------------------------------------------------------- 07-Oct-2005: ************ 06:26 NW - Faint and narrow fan-like front. It fades throughout C2. 16:06 NE - Gradual development of a faint loop along the streamer. It seems to appear after a kind of reconection event ('pair formation'--> corresponding infalling material). Couple more of similar events in the trailing material of the event (i.e., at ~ 19:31 UT on the northern leg, and at ~ 22:08 UT on the southern leg). ---------------------------------------------------------------------------------- 08-Oct-2005: ************ 00:06 NE - Narrow ragged front on the southern leg of event reported to start at 16:06 UT on previous day. It fades throughout C3. 01:27 S - Diffuse and ragged front that fades close to the inner edge of C3. 18:26 SE - Diffuse and elongated curved feature. 22:06 WNW - Ragged front along streamer that fades very close to the inner edge of C3. ---------------------------------------------------------------------------------- 09-Oct-2005: ************ 04:26 NE - Faint blob-like front. 13:27 SSE - Faint blob-like front. 15:50 E - Faint and ragged front. It fades throughout C3. ---------------------------------------------------------------------------------- 10-Oct-2005: ************ 09:06 ESE - Very faint and diffuse spray-like front. It fades throughout C2. 12:50 E - Very narrow loop-like front (jet-like). It fades close to the inner edge of C3. 21:26 E - Faint ragged front. ---------------------------------------------------------------------------------- 11-Oct-2005: ************ 00:06 N - Very faint and diffuse jet-like front. 06:50 E - Very faint and ragged loop front. Difficult to give an exact time of first appearance. 18:26 WNW - Diffuse loop front. ---------------------------------------------------------------------------------- 12-Oct-2005: ************ 02:50 SW - 'Pair formation' at PA 218 (~ 4.15 solar radii). 06:26 W - Bright ragged loop front. Faint extensions to N and S. 19:27 W - Ragged loop front. By 18:50 UT, a brightening can already be discerned. 21:26 WSW - Asymmetric and ragged loop front (brighter to N). ---------------------------------------------------------------------------------- 13-Oct-2005: ************ 03:26 WNW - Several faint (and relative narrow) loop fronts. 23:26 S - Faint and very narrow loop front. 23:50 SE - Couple of ragged blob-like fronts can be discerned. ---------------------------------------------------------------------------------- 14-Oct-2005: ************ 10:50 SE - Very faint front ('V-shaped'). 16:26 SE - Faint and narrow loop-like front. 23:06 ENE - Diffuse and ragged loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 15-Oct-2005: ************ 02:26 SW - Diffuse front ahead (a little bit to S) of a bright ragged loop front. They fade throughout C3. ---------------------------------------------------------------------------------- 16-Oct-2005: ************ 07:27 ESE - Very faint loop-like front that fades throughout C2. 09:26 E - Diffuse and narrow loop-like front that fades throughout C3. 09:50 E - Loop front developing a little bit to N of (and slower than) previous event. It fades throughout C3. ---------------------------------------------------------------------------------- 17-Oct-2005: ************ 23:29 SE - Faint and very narrow (jet-like) loop-like front. ---------------------------------------------------------------------------------- 18-Oct-2005: ************ NW - Slow development of a system of faint loops along the streamer, apparently starting early in the afternoon. Difficult to give an exact time of first appearance. Clearly discernible by the end of the day. 16:29 ESE - Very narrow loop front (jet-like). Barely visible in C3. 17:06 SE - Very narrow, faint, and diffuse loop front. It fades throughout C2. ---------------------------------------------------------------------------------- 19-Oct-2005: ************ NW - The slow development of the system of faint loops along the streamer continues (streamer blowout close to midday). 05:06 NNW - Diffuse jet-like front. 08:53 NNW - Another jet-like front. 12:29 NW - Faint and diffuse loop front a little bit to N of (and still partly superposed with) the trailing part of the development of the streamer blowout. 15:29 SW - Very faint ragged front. **** EIT Shutterless #21 Campaign between 17:00 - 19:40 UT. **** 17:48 E - Very diffuse and not-well-defined front. ---------------------------------------------------------------------------------- 20-Oct-2005: ************ 00:09 NW - In the trailing tail of the streamer blowout event on previous day, an elongated loop front develops. Some small ragged fronts along the day. **** LASCO Data Gap between 10:13 - 13:13 UT (C2 time). **** 15:36 SE - Diffuse and very narrow fan-like front. Another one (also very faint) seems to follow at 17:04 UT. ---------------------------------------------------------------------------------- 21-Oct-2005: ************ 07:48 S - Very narrow loop front (jet-like) developing toward SSW. 08:13 E - Initially bright loop front, barely visible in C3. 12:23 NE - Jet-like front. 14:57 WNW - Ragged front starts to be discernible at around 3.5 solar radii. It fades throughout C3. Gusty outflow all above the western limb since earlier in the day. 17:38 WNW - Another ragged (loop-like) front. It fades throughout C3. ---------------------------------------------------------------------------------- 22-Oct-2005: ************ 07:31 WSW - Initially bright loop front above the WSW Limb. Couple of hours HALO later, diffuse extensions can be discerned to N and S, the C2 occulting disk being completely surrounded by 10:56 UT. The LE of the loop-like feature previously described (on WSW) is by that time almost at the end of the C2 FOV, while the halo signature on W is barely above the limb. By 09:06 UT, a system of expanding loops follows. The event (i.e., the first loop front) is first seen in C3 at 09:42 UT on WSW. A very ragged full halo signature can be clearly seen in C3 by 17:18 UT. The mean plane-of-sky speed of the LE of the event at PA 246 was about 290 km/sec (based on C3 data). The corresponding Height- time diagram shows a clear acceleration profile in the C3 FOV. GOES recorded very low X-ray activity all along the day (A-class). Likewise, no significant frontsided activity is revealed in EIT 195 images. The event has therefore been determined as a faint Full Halo Event, backsided. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20051022 08:06 NE - Faint and arrow (jet-like) loop front that fades throughout C2. 07:31 E - Kind of 'reconnection event' at PA 98 (around 3.85 solar radii): asymmetric loop-like front going out, and corresponding infalling feature. 12:54 SW - Elongated and ragged narrow loop front in the trailing material (at roughly the southern leg) of the system of loops reported to start at 09:06 UT (see event at 07:31 UT). 20:58 NNW - Small and elongated loop-like front. ---------------------------------------------------------------------------------- 23-Oct-2005: ************ E - Several 'reconnection-type' events all along the day. Gusty outflow and infalling material. 08:06 SSW - Diffuse and ragged loop front that fades throughout C2. 12:30 SSW - Very faint and diffuse front develops as an elongated loop-like front. It fades throughout C3. 18:06 N - Ragged (not-well-defined) front. ---------------------------------------------------------------------------------- 24-Oct-2005: ************ 02:54 NW - Loop front with structured interior. EIT 195 images show a filament eruption on NW between 01:13 - 05:12 UT. 04:06 NW - A faster (and fainter) front, rather elongated, develops superposed in the LOS with previous event. By 05:54 UT another faint loop-like front can be discerned a little bit to N and ahead of event reported to start at 02:54 UT. 10:30 W - Faint and diffuse front that seems to disturb the development of the event reported to start at 02:54 UT. Small blob-like fronts well into next day. 15:54 SSW - Extremely faint and diffuse front (barely visible). By that time, also a wide and very faint system of expanding loop fronts seems to develop toward SSE spanning all the way from the SE limb up to past the S Pole. 16:54 E - Diffuse loop front. By the end of the day (~ 23:54 UT), a faint loop front starts to be discernible in the trailing material. They both fade throughout C3. ---------------------------------------------------------------------------------- 25-Oct-2005: ************ W - Some small ragged blob-like fronts all along the day. 07:31 SE - Behind the system of loop fronts reported to start at 15:54 UT on previous day, another system of expanding loops develops, apparently moving faster. ---------------------------------------------------------------------------------- 26-Oct-2005: ************ 03:30 NE - Faint ragged front. 10:30 ESE - Faint loop-like front. 11:30 WSW - Slow development of a system of loops along the streamer. By 18:38 UT, a wide and diffuse expanding loop front develops superposed in the LOS with the system of loops, which by then seems also to start expanding. **** Segment 2 of the EIT Shutterless campaign #21 between 17:00 - 19:40 UT. **** ---------------------------------------------------------------------------------- 27-Oct-2005: ************ 01:31 W - Narrow front in the trailing material of event reported to start at 11:30 UT on previous day. It fades throughout C2. 04:30 NE - Jet-like front. 10:30 SE - Elongated loop front. 11:06 WSW - Ragged and elongated loop front. Difficult to give an exact time of first appearance. It fades throughout C3. 15:30 NE - Very narrow and elongated loop front followed by a couple of similar narrow fronts at 16:54 and 19:54 UT. 19:31 SW - Ragged loop front. ---------------------------------------------------------------------------------- 28-Oct-2005: ************ 12:06 ENE - Diffuse and narrow loop front followed by another one at 14:30 UT. They fade throughout C3. 14:30 SW - Ragged and elongated front. 17:54 SE - Slow development of a system of very faint and diffuse loops. Difficult to give an exact time of first appearance. Practically not discernible in C3. A more clear loop-like front can be seen then at ~ 22:30 UT. ---------------------------------------------------------------------------------- 29-Oct-2005: ************ 02:30 WSW - Faint and ragged front that fades throughout C3. 16:06 WSW - Another faint and ragged front that fades throughout C3. ---------------------------------------------------------------------------------- 30-Oct-2005: **** No significant activity. ************ ---------------------------------------------------------------------------------- 31-Oct-2005: ************ 16:30 SW - Diffuse jet-like front that quickly fade. 21:30 WNW - Faint and diffuse front that quickly fades. ================================================================================== 01-Nov-2005: ************ 11:30 N - Very faint and diffuse jet-like front that quickly fades. Otherwise, no significant activity. ---------------------------------------------------------------------------------- 02-Nov-2005: ************ 02:54 WSW - Jet-like front developing toward W. 04:30 W - Initially diffuse brightening develops as a bright loop front followed by a cavity, and a bright inner core (prominence material). 12:54 SSW - Jet-like front. 16:54 SSW - Another faint jet-like front. ---------------------------------------------------------------------------------- 03-Nov-2005: ************ W - Pseudo-continuous outflow all along the day. 06:06 SE - Extremely faint and diffuse loop front, barely visible even in C2. ---------------------------------------------------------------------------------- 04-Nov-2005: ************ W - Gusty outflow all along the day. 14:30 E - Faint and diffuse front that quickly fades. ---------------------------------------------------------------------------------- 05-Nov-2005: ************ 20:30 NW - Very faint and diffuse jet-like front. Otherwise, no significant activity. ---------------------------------------------------------------------------------- 06-Nov-2005: **** No significant activity. ************ ---------------------------------------------------------------------------------- 07-Nov-2005: ************ 02:30 NNE - Diffuse jet-like front. 05:30 NE - Very slow development of an extremely faint (in fact, barely discernible) and diffuse expanding front, that seems to extend up to past the N Pole. Difficult to give an exact time of first appearance. It is apparently first seeen in C3 above the N Pole by around 16:42 UT, fading by the end of the day. 08:30 SW - Initially bright loop front. It fades throughout C3. Gusty outflow. 15:30 NNW - Diffuse jet-like front. 23:06 NE - Another faint and expanding asymmetric loop front (though much clearer than the one reported to start at 05:30 UT). It extends up to past the N Pole. It is first seen in C3 at 00:42 UT on next day, barely above the NNE limb. Note that a diffuse and fainter expanding front seems to develop at the time of the event previously described (superposed in the LOS and apparently faster), mainly toward N. ---------------------------------------------------------------------------------- 08-Nov-2005: ************ 06:30 WSW - Ragged loop front that fades throughout C2. 11:54 NW - Faint and expanding loop front. It fades throughout C3. 17:54 NW - Blob-like front. It fades throughout C3. ---------------------------------------------------------------------------------- 09-Nov-2005: ************ 00:06 SW - Faint and diffuse front that quickly fades. By 01:31 UT, an extremely faint front can be seen above the S Pole, fading close above the C3 occulting disk (on the S Pole). 03:30 W - Initially bright and asymmetric front. GOES reported a C1.2 X-ray flare on NOAA AR 10820 (S16W77) between 02:41 - 03:06 UT with peak emission at 03:01 UT. 07:31 E - Faint jet-like front. 11:54 ENE - Extremely faint front that quickly fades. ---------------------------------------------------------------------------------- 10-Nov-2005: ************ 00:06 ENE - Extremely faint loop-like front starts to develop well above the C2 occulting disk. Difficult to give an exact time of first appearance. 08:30 E - Elongated front. 11:30 NW - Jet-like front. 18:06 SSW - Slow development of a system of faint loops. Difficult to give an exact time of first appearance. 20:58 N - Jet-like front that quickly fades. Another one on NNE. 21:30 E - Faint and elongated loop-like front. ---------------------------------------------------------------------------------- 11-Nov-2005: ************ 07:31 E - Faint and elongated front. Otherwise no significant activity. ---------------------------------------------------------------------------------- 12-Nov-2005: ************ 00:06 SSW - Faint and very diffuse loop front. It fades throughout C2. 00:54 WNW - Blob-like front (barely visible in C3) developing toward W. Another one (much smaller) at 06:54 UT. The latter is only visible in C2 (and just close to the limb). 01:31 ENE - Faint loop-like front that fades throughout C2. 10:56 NNE - Jet-like front. 16:30 SE - Diffuse and elongated fan-like front. It fades throughout C3. 17:54 SSW - Very narrow loop-like front that fades throughout C3. 20:30 SW - Blob starts to be discernible as a result of an apparently reconection-type event. Difficult to give an exact time of first appearance. Well seen in C2 at the beginning of next day. ---------------------------------------------------------------------------------- 13-Nov-2005: ************ **** NOTE: **** GOES recorded multiple B- and C-class events on NOAA AR 10822 (~S09E77) **** during the day, including an M2.5 X-ray flare (S07E77) peaking at 14:51 UT. **** No clear signatures of associated events on C2 except for a pseudo- **** continuous outflow all above the E limb. 00:54 N - Jet-like front that quickly fades. 05:54 WSW - Bright ragged loop front. 22:30 E - Faint (expanding) loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 14-Nov-2005: ************ **** NOTE: **** C-class activity on NOAA AR 10822 continues. Couple of M-class X-ray flares **** (peaks at 04:21 UT and 14:21 UT). Pseudo-continuous outflow on E continues. 04:54 ESE - Diffuse front that fades close to the inner edge of C3. GOES recorded an impulsive M2.6 x-ray flare on NOAA AR 10822 (S06E63) between 04:16 - 04:27 UT with peak emission at 04:21 UT. 08:30 S - Very faint and diffuse expanding loop front. First seen in C3 at 11:18 UT (faint). It fades throughout C3. ---------------------------------------------------------------------------------- 15-Nov-2005: ************ **** NOTE: **** C-class activity on NOAA AR 10822 continues. M1.4 X-ray flare peaking at **** 17:51 UT. 06:30 SW - Blob-like front. 12:54 NE - Diffuse jet-like front. 16:30 NW - Loop front along the streamer. It fades close to the inner edge of C3. ---------------------------------------------------------------------------------- 16-Nov-2005: ************ 13:31 S - Extremely faint loop front. 16:30 W - Partial Halo Event associated to filament eruption on NW Partial quadrant. Likely signatures of the event were first seen in C2 Halo at 16:30 UT on the W Limb, developing as a relatively bright loop front with faint and diffuse extensions to N. By 18:06 UT, a faint, diffuse, and ragged loop front develops toward SW, spanning all the way from the W limb up to past the S Pole, apparently disturbing the southern leg of the loop first mentioned. The loop front is first seen in C3 above at 18:18 UT just appearing above the W Limb. Clear signatures of the second front can be seen above the SW limb by 20:18 UT. By this time, it becomes difficult to disentangle both features. The whole event spans ~ 190 deg (from PA 155 - 345) in the C3 FOV at 23:42 UT. The mean plane-of-sky speed of the outermost edge of the event at PA 261 was ~ 314 km/sec, showing a slight acceleration. GOES recorded multiple B-class X-ray flares during the day, all from NOAA AR 10822 in addition to a C5.9 X-ray flare at S07E36 (AR 10822) between 11:41 - 12:48 UT with peak emission at 12:13 UT. EIT 195 images show a brightening on AR 10822 peaking at 12:12 UT. No dimming can be discerned. There is then a gradual brightening on the same AR starting at around 14:24 UT and peaking at 14:36 UT, not correlated with any peak in X-rays. This second brightening seems to happen a little bit after the beginning of the eruption of an apparently small filament located close to the equator in the NW quadrant (eruption that is then seen developing mainly toward W). A dimming region develops to the NE and W of the original filament location. It is the filament eruption (which apparently started at around 13:48 UT) the most likely EIT counterpart of the LASCO event. The event has therefore been determined as a Partial Halo Event, front- sided, most likely associated with a filament eruption. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20051116 ---------------------------------------------------------------------------------- 17-Nov-2005: ************ 02:30 SW - Small and elongated loop front that quickly fades. 06:30 E - Fan-like front. 18:06 SE - Very diffuse loop-like front. It fades throughout C2. 18:30 NW - Reconection-type event (at around PA 307, 2.85 solar radii): blob-like front coming out with corresponding infalling material. 23:30 NE - Elongated fan-like front. ---------------------------------------------------------------------------------- 18-Nov-2005: ************ 00:30 E - Jet-like front. 14:54 ESE - Faint and diffuse loop-like front that fades close to the inner edge of C3. 19:31 W - Ragged loop front. It fades close to the inner edge of C3. A brightening can be seen since earlier (~ 18:30 UT). ---------------------------------------------------------------------------------- 19-Nov-2005: ************ SSW - Slow development of a system of faint loops since late on previous day. A vary faint and diffuse pattern ahead, developing above the S Pole. Difficult to give an exact time of first appearance. See next event. 05:54 SSW - Complex Partial Halo Event. Signatures of the complex event Partial started to be seen in C2 at 05:54 UT barely above SSW limb Halo (hereafter Feature #1), developing behind a rather faint system of faint and diffuse expanding loops that started to be discerned late on previous day. Feature #1 develops as an asymmetric and expanding loop front. It is followed by a system of wide and expanding (faint) loops (Feature #2) developing above the S Pole (it starts to be discerned at around 08:30 UT). By 14:54 UT, an apparently distinct (expanding) loop front (Feature #3) follows on the S Pole. A relatively bright and narrow loop front, first seen at 15:06 UT, develops on the ESE superposed in the LOS with the corresponding leg of Feature #3. By the time, and still a little bit to N (on E limb) an elongated front developing apparently faster can also be discerned. The complex event is first seen in C3 around 12:18 UT above the WSW limb (Feature #1) developing as a ragged loop front, not too wide. By 16:42 UT, Feature #3 starts to be discerned above the S Pole. As seen in C3, it is Feature #3 the one that clearly develops as a Partial Halo Event. Feature #2 is to faint to be properly distinguished. Feature #3 spans in C3 at 21:18 UT about 170 deg (from PA 95 - 265). The mean plane-of-sky speed of Feature #3 at PA 185 was ~ 325 km/sec. For completeness, the mean plane-of-sky speed of Feature #1 at PA 245 was 225 km/sec. Both cases show practically no acceleration. GOES recorded by the time just a couple of B- class X-ray flares from NOAA AR 10822: i) a B6.0 peaking at 04:16 UT at S07W02, and ii) a B8.2 peaking at 09:42 UT at S07W05. EIT 195 images do not show any significant activity on the disk, other than small brightenings on AR 10822 associated to the B- class X-ray flares. In summary, although several components were described, it is Feature #3 the one that apparently shows up with all the characteristics of a Partial Halo Event. And based on EIT, it looks like Feature #3 was originated on the backside of the Sun. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20051119 14:54 S - Expanding loop front (see Feature #3 in previous event). 15:06 ESE - Loop front superposed in the LOS with the leg of previous event on the eastern hemisphere. At the same time, an elongated and ragged front develops a little to N (on the E limb). See Partial Partial Halo Event reported to start at 05:54 UT. 18:31 WSW - Ragged loop front. ---------------------------------------------------------------------------------- 20-Nov-2005: ************ 01:54 ENE - Elongated and narrow fan-like front. 09:30 E - Elongated front "pushed" toward the equator during its early development. 17:54 SSW - Faint and ragged wide front. Barely visible in C3. 17:54 ESE - Slow development of a system of faint loops results in a nice CME with inner core, which starts to be clearly seen at the beginning of next day (see also next event). Difficult to give an exact time of first appearance. 21:30 S - Complex Partial Halo Event. Signatures of the event started to Partial be seen in C2 at 21:30 UT barely above the S Pole (Feature #1). Halo By 21:54 UT, an apparently new loop starts to be seen above the SSW limb (Feature #2). The latter develops mainly toward SW followed by a system of expanding loops, moving apparently faster than Feature #1, and hence disturbing its development (Feature #1 appears to be pushed from behind). Note that since earlier, i.e. starting at around 17:30 UT, the slow development of a system of faint loops can be discerned on ESE (see previous event). By the end of the day, it superposes in the LOS with the development of Feature #1, showing up later developing as an expanding loop front with inner core. It is worth to mention that Feature #1 seems to be also disturbed by this other event. The complex event spans in the C2 FOV at 00:54 UT (on 11/21) about 205 deg (from PA 60 - 265). The complex event is first seen in C3 on 11/21 at 00:18 UT above the SSW limb. During its development in C3, it becomes difficult to disentangle features #1 and #2. The mean plane-of-sky speed of the outermost front of the complex event at PA 204 was ~ 390 km/sec, showing practically no acceleration. GOES recorded a couple of C-class X-ray events on 11/20 from NOAA AR 10822. They peaked at 07:36 UT (S09W17), and 15:20 UT (S08W22). Hence, their time frame does not match that of the LASCO events. On the other hand, a couple of B-class X-ray flares from AR 10822 occurred later in the day, i.e. a B2.8 peaking at 21:55 UT (S07W26), and a B7.5 peaking at 23:55 UT (S06W29). EIT 195 images do not show significant activity by the time of the LASCO event, save the small brightenings on AR 10822 associated to the B-class X-ray flares. In summary, the complex event has therefore been determined as at least a Partial Halo Event, most probably backsided, based on the lack of a likely EIT counterpart of the LASCO events on the solar disc. See movies and images of the event at: ftp://ares.nrl.navy.mil/pub/lasco/halo/20051120 ---------------------------------------------------------------------------------- 21-Nov-2005: ************ ESE - Pseudo continuous outflow. Some reconection-type events during the day (on ESE and SE). In particular at: 12:30, 14:54, 18:06, and 22:30 UT. Also several ragged loop fronts on ENE during the day. 18:54 SSE - Faint and diffuse front followed at 22:06 UT by a diffuse and expanding front extending toward SW. ---------------------------------------------------------------------------------- 22-Nov-2005: ************ 03:30 E - Not-well-defined and faint front that fades throughout C3. Some small blob-like fronts all across the eastern hemisphere during the day. 07:54 SSE - Elongated and ragged front, preceded by a not-well-defined (small) front at 06:30 UT. Small ragged blob-like fronts during the rest of the day. **** LASCO Data Gap between 20:43 - 24:00 UT (C2 time). **** ---------------------------------------------------------------------------------- 23-Nov-2005: ************ **** LASCO Data gap between 00:00 - 08:15 UT (C2 time). **** 09:06 SE - Ragged blob-like front already under development after data gap. 10:30 NW - Ragged and diffuse front. It fades throughout C2. 15:30 NW - Ragged front preceded by a very faint and diffuse (expanding) brightening to N (first seen above the NNW limb at 14:54 UT). 23:54 NW - Another ragged front accompanied by a wide, diffuse, faint, and expanding front to N, which develops apparently faster. By 00:30 UT on next day, the expanding front seems to fully surround the C2 occulting disk. However, the halo signature is so faint that fade throughout C2. ---------------------------------------------------------------------------------- 24-Nov-2005: ************ 04:54 W - Diffuse front that fades throughout C2. 13:31 N - Faint and wide expanding front that seems to cover the whole northern hemisphere in C2. First seen in C3 at 14:42 UT, just appearing above the NNW limb. It fades then throughout C3. 19:31 SW - Narrow fan-like front that fades throughout C2. ---------------------------------------------------------------------------------- 25-Nov-2005: ************ 15:30 N - Diffuse and wide front, first clearly seen in C3 at 17:18 UT. It fades then throughout C3. 23:06 NNE - Jet-like front. ---------------------------------------------------------------------------------- 26-Nov-2005: ************ 07:31 W - Not well-defined couple of faint fronts that fade throughout C2. 09:30 SE - Elongated and diffuse loop-like front. Another one at 10:34 UT. 16:54 W - Extremely faint front that seems to extend all the way up to almost the S Pole. Difficult to give an exact time of first appearance. First seen in C3 at 18:18 UT, clearer than in C2. 17:30 NW - Diffuse jet-like front. ---------------------------------------------------------------------------------- 27-Nov-2005: ************ 03:30 ENE - Elongated and very narrow front that apparently fades in C2. By that time, a loop front develops to N of it, along the streamer. Another one at 05:54 UT. 10:34 W - Slow development of a system of faint loops. 12:54 WSW - Narrow loop-like front. 14:06 NNW - Jet-like front. 15:54 ENE - Very narrow loop-like front. ---------------------------------------------------------------------------------- 28-Nov-2005: ************ 06:54 WNW - Slow development of a system of very faint loop fronts. Difficult to give an exact time of first appearance. 09:30 W - Diffuse brightening just appearing develops as a big and ragged loop front. It partly superposes in the LOS with the slow development of the system of faint loops on WNW (gusty outflow follows afterward on WNW). ---------------------------------------------------------------------------------- 29-Nov-2005: ************ 01:31 SE - Extremely faint (and diffuse) loop front. It fades throughout C2. 17:30 W - Very bright loop front with very faint and diffuse extensions to N and S. By 17:54 UT the faint extensions seem to cover the C2 occulting disk. Some small ragged loop fronts in the trailing material on W (e.g., at 20:30 UT on WSW, and at 00:30 UT -next day- on WNW). The event is first seen in C3 at 18:18 UT. The extensions can be clearly seen developing above the S Pole by 19:42 UT. Signature too faint (if any) to be discernible above the N Pole. GOES reported a C4.0 X-ray flare on NOAA AR 10824 (S14W45) between 16:38 - 17:33 UT with peak emission at 17:09 UT. ---------------------------------------------------------------------------------- 30-Nov-2005: ************ W - Some small and faint blob-like fronts during the day in the aftermath of event reported to start at 17:30 UT on previous day. 07:31 NE - Very faint expanding loop front. First seen in C3 at 10:42 UT. It fades throughout C3. 16:54 ENE - Diffuse and elongated loop front. It fades close to the inner edge of the C3 FOV. ================================================================================== 01-Dec-2005: ************ **** NOTE: **** GOES reported multiple B- and C-class X-ray activity on NOAA AR 10826, all **** along the day. The center of activity was located at around S04E31 at the **** beginning of the day and around S04E20 by the end of the day. Some LASCO **** events above the E Limb during the day. They are most likely associated to **** the X-ray activity just mentioned (Some of them reported below. See -1-). 00:30 E - Series of elongated loop fronts. In particular at 00:30, 02:06, and 03:06 UT. Signatures more likely related to the X-ray activity on AR 10826 (-1-). 02:54 W - Bright and ragged loop front with some trailing material. Some reconection type events ('pair formation') in the trailing material all along the day. GOES reported a C2.1 X-ray flare on NOAA AR 10824 (S16W66) between 02:18 - 02:57 UT with peak emission at 02:38 UT. 08:06 E - Bright and elongated loop front developing slightly toward ESE (-1-). 10:30 S - Narrow and faint fan-like front. It fades in C2. 12:30 E - Another bright and elongated loop front developing slightly toward ESE (-1-). 17:54 E - Couple of faint elongated loop fronts developing slightly toward ESE. ---------------------------------------------------------------------------------- 02-Dec-2005: ************ **** NOTE: **** Several C- and M-class X-ray flares on NOAA AR 10826 during the day. **** In particular: **** - Impulsive C1.7 (S04E17), peak at 00:34 UT **** - Impulsive C1.3 (S04E17), peak at 02:11 UT **** - M6.5 (S03E19) between 02:42 - 03:00 UT, peak at 02:52 UT **** - C4.9 (S02E14) between 05:52 - 06:09 UT, peak at 06:00 UT **** - M7.8 (S03E14) between 10:05 - 10:25 UT, peak at 10:12 UT **** - M1.0 (S03E07) between 20:01 - 20:52 UT, peak at 20:30 UT **** - M2.0 (~S02E08) between 20:57 - 21:37 UT, peak at 21:19 UT **** Some LASCO events may be associated to some of them. 01:31 E - Big and bright ragged loop front with trailing material. EIT 195 images show a CME either at or just over the ENE Limb between 00:48 - 02:36 UT. 04:54 ESE - Elongated and relatively narrow loop front. 07:31 ESE - Diffuse brightening just appearing develops as a bright loop front (much brighter to S). Faint loop-like extensions to S (not discernible in C3). By 07:54 UT, a ragged and apparently asymmetric loop front develops on the E limb, at a position that seems to match that of the apparent northern leg of the bright loop front. 11:06 SSW - Very faint and diffuse (wide) loop front, spanning up to almost the W Limb. Apparently not discernible on C3. 11:30 NE - Elongated (and not-well-defined) loop front along the streamer. It was preceded at 08:06 UT by a similar front, though in this case it is difficult to discern whether it was part of previous event or an independent feature. 15:30 ESE - Elongated (fan-like) loop front. It fades throughout C3. 16:06 E - Ragged blob-like front starts to be discerned slightly above the C2 occulting disk. 22:24 ESE - Diffuse and elongated loop front that fadec close to the inner edge of C3. **** EIT CCD bakeout (+ pre and post cal) between **** **** Dec 2 ~ 18:12 UT - Dec 18 21:00 UT. **** **** ==> No EIT images during that period. **** ---------------------------------------------------------------------------------- 03-Dec-2005: KEYHOLE ************ **** NOTE: **** Multiple B- and C-class X-ray activity continues on NOAA AR 10826 (AR close **** or around the central meridian). 01:24 ESE _ Elongated loop front with faint loop-like extensions to S. It fades throughout C3. System of faint loops starts to develop on E by 02:12 UT, fading then throughout C2. Some reconection type events on NE. 09:00 SE - Slow development of a system of faint expanding loop fronts. It fades throughout C3. 16:48 W - Diffuse brightening precedes the slow development of a system of faint loops. Apparently another structure, twisted, develops by 19:12 UT (though it is difficult to give an exact time of first appearance) superposed in the LOS. It seems to move faster. 20:24 ESE - Narrow loop front. Very faint expanding loop-like extensions develop to S. They superpose in the LOS with the still evolving slow event reported to start at 09:00 UT. ---------------------------------------------------------------------------------- 04-Dec-2005: KEYHOLE ************ **** NOTE: **** Multiple B-class X-ray activity continues on NOAA AR 10826. 01:24 WSW - Elongated loop front slightly curved toward S. It fades throughout C3. 01:36 N - Jet-like front. 11:24 SE - Very faint loop front with fainter extensions to S. 19:12 SE - Very faint expanding loop front. It fades throughout C3. ---------------------------------------------------------------------------------- 05-Dec-2005: KEYHOLE ************ 13:48 E - Ragged loop front. Very faint in C3. By 14:12 UT, an extremely faint and diffuse front starts to be seen on SE. Difficult to say whether it is associated to the ragged loop front. 17:48 E - Another ragged loop front. Also faint in C3, fading throughout its FOV. 21:36 E - Bright ragged loop front with apparently twisted trailing material. It fades throughout C3. ---------------------------------------------------------------------------------- 06-Dec-2005: KEYHOLE ************ 02:12 E - Apparently circular structure in the trailing material of event reported to start at 21:36 UT on previous day. 21:12 NW - Extremely faint loop front starts to be discernible above the NW limb. 23:24 E - Ragged front that fades throughout C3. Gusty outflow well into next day. ---------------------------------------------------------------------------------- 07-Dec-2005: KEYHOLE ************ 05:12 SW - Kind of reconection event ("pair formation") well above the limb: very faint blob-like front and corresponding infalling material. Difficult to give an exact time of first appearance. 15:36 SW - Another "pair formation" event. 19:12 NE - Wide and expanding loop front with faint extensions that extend all above the N Pole up to the W Limb by 19:24 UT. The C2 occulting disk seems to be fully covered by the extension by 19:48 UT. The event is first seen in C3 above the ENE Limb at 20:18 UT with very faint extensions above the N Pole up to the W Limb. By 21:42 UT, the faint extensions make the event appear as a very faint full halo. The bulk of the ejection moves mainly toward ENE. The halo signature fades at the very beginning of next day. GOES reported a B5.5 X-ray flare on NOAA AR 10830 (N15E14) between 18:41 - 19:10 UT with peak emission at 18:52 UT. ---------------------------------------------------------------------------------- 08-Dec-2005: KEYHOLE ************ **** No significant activity. **** ---------------------------------------------------------------------------------- 09-Dec-2005: KEYHOLE ************ SW - Gusty outflow along a streamer all along the day. 14:00 SE - Faint and elongated loop front. It fades throughout C3. **** LASCO data gap between 14:36 - 16:48 UT (C2 time). **** 21:36 E - Diffuse loop front that fades throughout C2. ---------------------------------------------------------------------------------- 10-Dec-2005: KEYHOLE ************ NW - Very slow development of a system of faint loops -1- since late on previous day (difficult to give an exact time of first appearance). A narrow and apparently elongated (with a circular top) structure starts to be discernible by the end of the day. The event will result in a streamer blowout clearly seen in C3 on next day by around 10 UT. 00:12 NW - Diffuse front superposed in the LOS with -1- (see previous entry) and moving faster. 19:36 W - Top of a loop front just appearing preceded by a diffuse brightening. It develops as a rather big and twisted expanding structure. ---------------------------------------------------------------------------------- 11-Dec-2005: KEYHOLE ************ NW - Several small reconection type events during the day, along the thin current sheet left behind the event described at the very beginning of previous day. 11:36 WSW - Elongated and ragged loop front developing toward SW in the trailing material of event reported to start at 19:36 UT on previous day. It is followed at 17:00 UT by another elongated and ragged structure. 16:24 SW - A small and ragged blob-like front develops as a twisted (circular) structure in the C2 FOV, just a little bit to S of event reported to start at 17:00 UT - see previous entry - (and moving more slowly). 17:24 ENE - Diffuse brightening precedes the development of a loop front. A twisted (rather circular) structure follows by 18:00 UT, developing more slowly. It develops early on next day as a ballon-type CME (then well discerned in C3). ---------------------------------------------------------------------------------- 12-Dec-2005: KEYHOLE ************ NW - Gusty outflow along a streamer all along the day. 03:00 W - Faint and small elongated loop-like front. Another one at 04:36 UT. They both apparently fade throughout C2. 16:12 SW - Bright loop front, preceded by some gusty outflow in the form of small ragged fronts (in particular one at 09:48 UT). It superposes in the line of sight (at the beginning) with the slow development of a system of loops. 21:12 ESE - Diffuse and faint small loop front followed by a faint loop front at 21:48 UT. ---------------------------------------------------------------------------------- 13-Dec-2005: KEYHOLE ************ NW - Gusty outflow along a streamer continues all along the day. SW - The slow development of the system of loops continues (see entry at 16:12 UT on previous day). It shows up as a ballon-type CME after ~ 16:00 UT. Gusty outflow superposed in the LOS for most of the day. 04:00 WNW - Curved fan-like front. 06:48 W - Jet-like front, slightly curved toward S. 12:36 W - Slow development of a loop front with inner core (most likely prominence material). A diffuse brightening (top of the loop) can be seen above the limb since earlier (starting at around 12:00 UT). 15:12 WNW - A very narrow curved loop front (slightly curved toward S) can be seen developing to N of previous event. 15:24 WSW - Ragged front preceded by a very diffuse and faint front develops to S of event reported to start at 12:36 UT. 15:48 E - Ragged blob-like front start to be discernible. It fades throughout C3. 22:00 E - Bright loop front with bright inner part. ---------------------------------------------------------------------------------- 14-Dec-2005: KEYHOLE ************ 00:36 SE - Slow development of a jet-like front. 06:24 SW - Elongated and not-well-defined loop-like structure, followed by some small ragged fronts. 13:48 ESE - Faint and rather elongated loop front. It fades throughout C3. 19:12 E - Initially bright loop front. Development missed. 20:00 W - Diffuse and faint front developing slightly toward WNW. **** LASCO close doors ahead of maneuvers on 2005/12/15: **** **** Last C2 image before closing doors: 21:12 UT **** **** Last C3 Image before closing doors: 21:42 UT **** ---------------------------------------------------------------------------------- 15-Dec-2005: KEYHOLE = NO LASCO IMAGES = ************ **** LASCO doors CLOSED (S/C Maneuvers: 180 deg roll, SK, and MM). **** ---------------------------------------------------------------------------------- 16-Dec-2005: KEYHOLE ************ **** First C2 image after Maneuvers on 2005/12/15: 22:30 UT. **** **** First C3 image after Maneuvers on 2005/12/15: 22:34 UT. **** 22:48 W - Ragged loop front with twisted (rather circular) inner structure already under development after reopening doors. Gusty outflow afterward all along the next day. ---------------------------------------------------------------------------------- 17-Dec-2005: KEYHOLE ************ 04:12 NE - Faint and narrow front precedes the development of a brighter and ragged loop front, first seen at 05:48 UT. By 06:24 UT, very faint extensions can be seen above the N and S Poles. The extensions seem to fully surround the C2 occulting afterward. However, they are too faint and cannot be discerned at all in the C3 FOV. No significant X-ray activity was reported by GOES on the eastern hemisphere. 13:12 NE - Extremely faint ragged front precedes the development of a brighter and ragged loop front that starts to be seen at 14:24 UT. Extremely faint extensions seem to develop then above the N Pole. The ragged loop front fades throughout C3. ---------------------------------------------------------------------------------- 18-Dec-2005: KEYHOLE ************ 02:24 E - Elongated loop front that fades throughout C3. 02:48 NNW - Difuse brightening just appearing develops as a ragged front. Faint and diffuse extensions develop by 03:00 UT on NW, moving faster and spanning all the way up to past the S Pole (clockwise). Difficult to say whether these extensions are related or not to the ragged front on NNW. By 05:48 UT on, an extremely faint and asymmetric front seems to develop in the C3 FOV from the W limb up past the S Pole, quickly fading afterward. 03:00 SE - Slow development of a system of faint and expanding loop fronts. Difficult to give an exact time of first appearance. By around 14:36 UT, a new loop system seems to start pushing from behind. 13:12 ENE - Bright and elongated loop front. Very faint and diffuse expanding front by 13:36 UT. Kind of reconection type event in the trail of the elongated loop front (front that fades close to the inner edge of C3). 18:34 W - Much gusty outflow starts to be discerned that then superposes in the LOS with the development of an apparently twisted structure. 18:34 ENE - Very faint and ragged front that fades close to the inner edge of C3. 22:06 ENE - Another faint front. ---------------------------------------------------------------------------------- 19-Dec-2005: KEYHOLE ************ E - Pseudo-continuous outflow all along the day all across the eastern hemisphere. In particular, see entry at 02:50 UT. 02:50 ENE - Bright and elongated loop front with faint expanding extensions toward N. It fades throughout C3. Small ragged fronts develop on SE all along the day plus a faint loop front on ESE (well seen at ~ 04:06 UT). By 12:50 UT, a faint an expanding ragged loop front can be discerned on NE. Another one at 19:27 UT. 04:26 WNW - In the gusty outflow present since previous day, a faint loop front precedes the development of a ragged and relatively bright loop front on W. Difficult to give an exact time of first appearance. This ragged loop front is first seen in C3 at 09:18 UT. Trailing material. ---------------------------------------------------------------------------------- 20-Dec-2005: END OF KEYHOLE ************ W - Gusty outflow all along the day. 04:54 SE - Diffuse and ragged (faint) loop front. It fades close to the inner edge of C3. Gusty outflow well into next day. 12:30 N - Jet-like front that quickly fades. 20:30 ENE - Diffuse jet-like front in the gusty outflow. 22:30 W - Diffuse and ragged front that quickly fades in the gusty outflow. ---------------------------------------------------------------------------------- 21-Dec-2005: ************ W - Gusty outflow all along the day. ENE - Gusty outflow all along the day. 02:30 W - Not-well-defined front in the gusty outflow. It fades throughout C2. 06:30 ESE - Extremely faint and diffuse loop-like front that quickly fades. Gusty outflow all along the day. Also by that time, an asymmetric and ragged (very faint) loop front starts to develop on ENE, which fades close to the inner edge of C3. ---------------------------------------------------------------------------------- 22-Dec-2005: ************ 00:06 ENE - Very faint ragged loop front that fades throughout C2 in the gusty outflow. Another one at 02:54 UT. 06:06 ENE - Faint ragged loop front. It fades close to the inner edge of C3. 13:31 ENE - Elongated and narrrow ragged front, slightly curved toward S. 19:54 ENE - Diffuse loop front along streamer preceded by a very faint brightening at around 18:30 UT. Some infalling material on E. ---------------------------------------------------------------------------------- 23-Dec-2005: ************ 02:54 ENE - Very narrow (jet-like) loop-like structure, just S of streamer; also diffuse loop-like extension superposed in the LOS with the streamer. Some infalling material all above the E Limb. 05:30 N - Very faint jet-like front developing toward NNE. 11:06 ENE - Faint and diffuse front superposed in the LOS with streamer. It fades throughout C2. 15:30 WSW - Elongated fan-like front. It fades throughout C3. 21:30 ESE - Initially bright loop front that fades throughout C3. ---------------------------------------------------------------------------------- 24-Dec-2005: ************ 00:30 ESE - Faint and difuse front in the aftermath of event reported to start at 21:30 UT on previous day. It quickly fades. ---------------------------------------------------------------------------------- 25-Dec-2005: ************ 03:30 E - Very faint elongated ragged front that quickly fades. 04:30 WNW - Ragged loop front that quickly fades. 10:56 ESE - Very diffuse brightening develops as a diffuse loop front. It is immediately followed by a brighter ragged loop front. 13:31 NNE - Jet-like front. ---------------------------------------------------------------------------------- 26-Dec-2005: ************ 15:30 N - Faint jet-like front. 19:31 ENE - Very faint ragged front starts to be discernible already half way across the C2 FOV. Very difficult to give an exact time of first appearance. ---------------------------------------------------------------------------------- 27-Dec-2005: ************ 00:06 ENE - 'Pair formation' in the trailing part of the event reported to start at 19:31 UT on previous day (at ~ 4 solar radii, PA ~ 51). Difficul to give an exact time of occurrence. 08:54 NE - Faint blob-like front. It fades throughout C3. 18:30 NE - Very narrow fan-like front. It fades throughout C2. 20:30 N - Diffuse jet-like front followed by a similar event at 20:58 UT. ---------------------------------------------------------------------------------- 28-Dec-2005: ************ 03:06 SE - Diffuse brightening precedes the development of a big and expanding loop system. The diffuse brightening develops then as a diffuse loop front, wider than the loop system behind. By 06:30 UT, narrow and ragged fronts start to be seen apparently pushing the loop system from behind. In particular at: 06:30, 07:54, 08:54, 09:54, and 11:54 UT. The diffuse loop front is first seen in C3 all above the SE limb at 04:42 UT, followed at 05:18 UT by the loop system. The mean plane-of-sky speed of the LE of the diffuse loop front at PA 150 was ~ 374 km/sec, showing practically no acceleration. The whole event spans in the C3 FOV at 10:20 UT about 115 deg (from around PA 085 - 200). GOES recorded no significant X-ray activity by the time. 18:30 SE - Narrow front at the southern leg of a fainter loop front. It fades throughout C3. 22:30 SE - Diffuse loop front followed at 23:54 UT by a blob-like front on its southern leg, moving apparently faster. 23:30 ENE - Faint and diffuse loop front that quickly fades. GOES recorded a C1.2 X-ray flare on NOAA AR 10843 (N11E38) between 22:27 - 22:50 UT with peak emission at 22:38 UT. ---------------------------------------------------------------------------------- 29-Dec-2005: ************ SE - Intermittent ragged fronts moving toward the S Pole continue during the day. 11:30 SE - Complex Event (difficult to disentangle the sources of the Partial different components): Halo . Diffuse brightening at 11:30 UT, apparently the top of a system of loops that develops rather slowly. . By 14:06 UT, a fainter and more diffuse loop front (also wider) develops superposed in the LOS, moving faster. . By ~ 16:54 UT, a bright and relatively narrow and slow loop front follows (much brighter to S) [hereafter Structure #1]. . By ~ 20:58 UT, an asymmetric and expanding wide loop front with inner material develops behind (moving faster), extending up to past the S Pole (difficult to give an exact time of first appearance) [hereafter Structure #2]. Some trailing material. ==> Structures #1 and #2 seem to develop superposed on one another in the C3 FOV. The so complex structure is first seen in C3 above the SE limb at 21:18 UT developing as an asymmetric and expanding complex loop front. The mean plane-of-sky speed of the complex structure at its outermost part (at ~ PA 150) was ~ 480 km/sec, exhibiting a marked acceleration. The complex structure spans ~ 125 deg in the C3 FOV at 03:42 UT on next day (from ~ PA 100 - 225). Therefore, it can be catalogued as a Partial Halo Event. EIT 195 images show the formation of a small dimming region at around S15E05, extending toward S and starting at ~18:00 UT. Afterward, an expanding arcade forms above an extended filament channel located just South-East of disc center, probably indicating a filament eruption. GOES did not record significant X-ray activity by the time. However it did record a C1.1 X-ray flare on NOAA AR 10843 (N11E17) between 20:36 - 21:28 UT with peak emission at 21:06 UT (difficult to establish its connection with the LASCO event). In summary, the latter has therefore been determined as a Partial Halo Event, probably frontsided (as based on the EIT signatures). ---------------------------------------------------------------------------------- 30-Dec-2005: ************ 05:30 SE - Several small ragged fronts in the aftermath of the Partial Halo Event reported to start on previous day. Gusty outflow well into next day moving toward SSW (over the S Pole). 09:30 E - Bright ragged and relatively wide loop front. Some extremely faint expanding extension to S and N. Some trailing material (in particular small and narrow fronts at 18:30, 23:06, 01:31, 07:31, and 10:34 UT, the last three on next day). The event is first seen in C3 above the E Limb at 10:42 UT. GOES recorded no significant X-ray activity during the day (also quiet by EIT). 16:54 W - Extremely faint and diffuse brightening that quickly fades. EIT 195 images show a faint and backsided CME on WNW between 15:24 - 16:48 UT, probably associated to the extremely faint C2 event. ---------------------------------------------------------------------------------- 31-Dec-2005: ************ 12:06 W - Diffuse loop front. Apparently, a faint structure develops superposed in the LOS, fading very close to the inner edge of C3. 23:06 NNE - Faint jet-like front. ==================================================================================