LASCO Activity Report for
May 25, 2007 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

KEYHOLE Operations:
-------------------
26 m keyhole: 2007/05/18 - 2007/06/05
34 m keyhole: 2007/05/21 - 2007/06/01

While in Keyhole, improved cadence in LASCO C2 (12 min) and 
LASCO C3 (30 mins). 

EIT CCD bakeout ends on 2007/05/24.

EIT CCD Bakeout as originally planned: started on 2007/05/18 @ ~15:00 UT 
and ends on 2007/06/05.

Spacecraft Maneuvers on Tuesday 2007/05/29. 
(Station Keeping, Momentum Management, and 180 deg Roll.

LASCO will safe on 2007/05/28 @~ 12:00 UT and will recover 
on 2007/05/30 @~ 23:00 UT.

2007/05/24 (Thursday)

	00:00 - 12:36 UT	LASCO Data Gap (C2 time).

16:12 UT  S West	Very diffuse and faint expanding front developing
			slowly develops as a Faint Partial Halo Event. Due 
			to its faintness and slow gradual nature it is 
			difficult to give an exact time of first appearance. 
			Due to the Keyhole Operations there is a Data Gap
 			between 18:12 - 23:14 UT (C2 time) and therefore, 
			the development of part of the event in C2 is missed 
			(LE at about 4.1 solar radii by 18:12 UT). The event 
			was first seen in C3 on 2007/05/24 at 23:18 UT all 
			above the SW limb. The angular width by 01:18 UT (on
 			05/25) is about 170 deg (from about PA 150 - 320). 
			Last available C3 frame by the time of writing:
			03:42 UT. By that time, the event is practically no
 			longer discernible (LE at about 15 solar radii - at 
			PA 270-). The mean plane-of-sky speed of the LE at 
			PA 264 was ~ 265 km/sec, showing a slight acceleration
			(based on only 5 C3 frames). GOES recorded no
			significant X-ray activity during 05/24 (practically 
			below the A level). NO EIT images are availble.
			In summary, the event has been determined as a very
 			faint, at least Partial Halo Event. It was not
 			associated to significant X-ray activity. The 
			morphology of the event in C2 would seem to indicate
 			that the event is associated with a prominence 
			eruption. With the data at hand I cannot be certain
 			whether the event was front- or backsided.

	18:12 - 23:14 UT	LASCO Data Gap (C2 time).

2007/05/25 (Friday)

01:36 UT  ES East	Diffuse jet-like front.

Last C2 image available by the time of writing: 03:48 UT