LASCO Activity Report for
April 20, 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

- SOHO is in telemetry Submode 5 (since 2005/03/11 @ 15:00 UT).

- EIT 195 CME watch at half-res (512x512).
 
- Venus entered the C3 FOV from the right on 2005/02/26 
  (by the end of the day). Still visible.

2005/04/19 (Tuesday)

12:26 UT  WN West	Bright ragged loop front and twisted trailing material.

17:50 UT  WS West	Very faint and diffuse front that fades throughout C2.

17:50 UT  N Pole	Couple of faint blob-like fronts. They fade in C3.

22:06 UT  E Limb	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). 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).
			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. 

2005/04/20 (Wednesday)

03:26 UT  E Limb	In the aftermath of event reported to start at 22:06 UT
			on previous day, a faint and expanding ragged loop
			front develops.

08:26 UT  W Limb	Diffuse spray-like front.