LASCO Activity Report for
July 11, 2005 SOHO Science Daily Meeting

Event times are first frame seen in C2 camera unless otherwise noted.
These are preliminary observations for the daily SOHO science discussions.
Final analysis is reported on the Lasco CME list.
An archive of these reports is available.

Points Of Interest

On 2005/07/06, SOHO Telemetry Submode was changed to Submode 5 (support for
VAULT -Sounding Rocket Launch on 2005/07/07). Telemetry Submode will be
changed back to Submode 6 on 2005/07/08 at 15:00 UT.

During TM Submode 5, EIT 195 CME watch in half-res (512x512).

2005/07/08 (Friday)

07:27 UT  N East	Elongated loop front developing toward ENE.

07:27 UT  ES East	Slow development of a system of faint loops. Difficult
			to give an exact time of first appearance.

12:26 UT  E Limb	Faint front developing slightly toward ESE (partly
			superposed with the development of the system of faint
			loops). It fades close to the inner edge of C3.

17:31 UT  N Pole	Extremely faint and diffuse front. Next C2 image
	  		available (19:22 UT) shows a very faint expanding 
			system of loop-like 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.

19:22 UT  W Limb	Bright ragged loop front. Some infalling material (see
			previous event for some other details).

2005/07/09 (Saturday)

02:30 UT  NN East	Extremely faint expanding loop front. It fades close
 			to the inner edge of C3.

09:06 UT  E Limb	Small front.

13:31 UT  S East	Expanding 'half' loop fronts. They fade throughout C3.

13:31 UT  W Limb	Narrow and elongated front. It fades throughout C3.

21:54 UT  EN East	Bright loop-like front followed by a cavity and bright
			inner core. See next event for some other details on 
			this event.

22:30 UT  N West	Wide and ragged loop front front. Faint and diffuse
			extensions all above both poles can also be discerned. 
			By 23:06 UT, the C2 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.

2005/07/10 (Sunday)

06:06 UT  W Limb	Diffuse front. Developing missed in following data gap.

	06:54 - 20:58 UT	Temporary Data Gap.

NOTE:
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.

23:06 UT  W Limb	Bright loop front with twisted inner structure. Much
			gusty outflow afterward.

2005/07/11 (Monday)

00:30 UT  W Limb	Just after the event reported to start at 23:06 UT, 
			an apparently new bright and ragged front appears.

05:30 UT  WN West	Initially bright and relatively small loop front.

06:54 UT  W Limb	Initially bright and relatively small loop front that
			quickly fades. Gusty outflow continues on W.

13:54 UT  WN West 	Another initially bright and relatively small loop 
			front.

Time of the last C2 image analyzed: 16:30 UT.