LASCO Activity Report for
May 4, 2006 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

2006/05/03 (Wednesday)

00:30 UT  E Limb	Diffuse and very faint front develops slowly, slightly
			toward ENE. It fades throughout C3 (very faint). Some
			gusty outflow along the day, especially on ENE.

23:30 UT  S West	Elongated and apparently twisted feature. Some
			brightenings already seen since a little bit earlier.
			EIt 1985 images show a prominence eruption to S
			of NOAA AR 10875 between around 23:12 - 23:48 UT.

2006/05/04 (Thursday)

00:54 UT  SS East	Faint jet-like front that quickly fades.

01:31 UT  S West	Small brightening just appearing to S of event
			reported to start at 23:30 UT, develops as a ragged
			and expanding loop front [1]. It is followed by a 
 			structured core (its inner front first seen in C2 at 
			02:54 UT) [2]. By 03:30 UT, a system of faint and 
			expanding loop fronts start to ve visible above the
			S Pole [3]. By 06:54 UT this system of loops spans
			~ 145 deg (from PA 110 - 255). Feature [1] is first 
			seen in C3 appearing above the SW Limb at 03:18 UT.
			Feature [2] follows behind at 04:42 UT. Finally,
			Feature [3] appears above the S Pole at 05:42 UT,
			partly superposed in the LOS with [2]. The mean plane-
			of-sky speed of the different features involved is
			as follows (based on C3 data):
			Feature [1] at PA 226: 520 km/sec (no acceleration)
			Feature [2] at PA 225: 400 km/sec (no acceleration)
			Feature [3] at PA 187: 300 km/sec (no acceleration).
			The last measurement is not that reliable due to the
			faintness of its LE (and superposition with Feature
			[2]. GOES reported no significant X-ray activity by 
			the time prior to the LASCO C2 event, though it 
			recorded a B3.7 X-ray flare on NOAA AR 10876 (S17W41)
 			between 03:28 - 05:00 UT with peak emission at 
			04:35 UT. EIT 195 images shows between ~ 00:24 - 01:36
			UT the eruption of the rest of the filament (see entry
 			at 22:30 UT on previous day), between AR 10876 and E05.
 			It is visible at least as far as skirt of the South
 			Polar Coronal Hole at ~ S60. EIT shows then, between 
			~ 01:13 - 06:48 UT, the slow evolution of post-CME 
			loops to SE of AR 10876. Given the observational
			characteristics of the event C2 and C3 the event has
 			therefore been catalogued as a Partial Halo Event,
 			frontsided, associated to a filament eruption. 

07:54 UT  N West	Faint and elongated front starts to be discernible.

Last C2 image available by the time of writing: 12:06 UT