LASCO Activity Report for
November 17, 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

2005/11/16 (Wednesday)

13:31 UT  S Pole	Very faint loop front.

16:30 UT  W Limb	Partial Halo Event associated to filament eruption on 
			NW quadrant. Likely signatures of the event were first
		 	seen in C2 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, frontsided,  most
			likely associated with a filament eruption. 

2005/11/17 (Thursday)

02:30 UT  S West	Small and elongated loop front that quickly fades.

06:30 UT  E Limb	Fan-like front.

Last C2 image available by the time of writing: 09:06 UT.