LASCO Activity Report for
July 21, 2004 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

2004/07/20 (Tuesday)

00:54 UT  E Limb	Initially bright ragged loop front that fades throughout
			C3.

04:30 UT  E Limb	Another ragged loop front (slightly brighter), with
 			apparently twisted trailing material. It fades in C3.

04:54 UT  S East	Elongated and ragged loop front along streamer. It fades
			throughout C3. Gusty outflow,

05:30 UT  W Limb	Elongated loop front that fades throughout C2.

13:31 UT  N Pole	Bright loop front rising above the N Pole develops
			as a 'partial' Halo CME. By 15:06 UT the front spans 
			in C2 ~ 164 deg, from PA ~ 280 - 084. Note also the 
			very faint extensions developing mainly toward 
			S and SE, and a diffuse loop front on SW. The bright 
			loop front is first seen in the C3 FOV at 14:18 UT, 
			while a much fainter front is also seen developing 
			toward S and SE (already farther out), though quickly
			fading. Later, a wide faint front developing toward W
			can also be discerned. The events were associated with
			complex solar activity reported by GOES, related to 
			NOAA AR 0652. That AR produced several C-class flares
			during the last 24 hours and one M-class flare. In
			particular, GOES recorded an M8.6 X-ray flare (N10E33)
			between 12:22 - 12:45 UT with peak emission at 12:32 UT,
			which was associated the bright front loop mentioned
			above. EIT Fe XII images show a strong brightening on 
			the aforementioned AR starting at 12:24 UT and reaching
			its peak at 12:36 UT. Afterward, an intensity disturbance
			(wave) is seen traveling across the disk mainly toward
			NW. Despite the	faintness of the extensions developing 
			to S and W, it is worth to mention that, before the
			brightening recorded by EIT at 12:24 UT, material is 
			seen to be ejected from the AR 0652 mainly toward SW
			(more precisely, starting at ~ 11:12 UT). The time
			coincides with a C6.0 X-ray flare recorded by GOES from
			NOAA AR 0652 (N03E34) between 11:01 - 11:37 UT with peak
			emission at 11:26 UT. Therefore, the faint extensions
			mentioned could probably be associated with these events.
 
18:54 UT  N West	Ragged loop front preceded by a fainter envelope in the
			trailing material of the 'Partial' Halo CME. It is 
			followed at ~23:30 UT by a kind of 'blob-like' feature.

21:54 UT  S East	In the gusty outflow along streamer, relatively bright
			and elongated loop front followed at 00:30 UT on next 
			day (a little bit to N) by a ragged loop front.

23:54 UT  W Limb	Spray-like front. It fades throughout C3.

2004/07/21 (Wednesday)

06:06 UT  SS East	Ragged loop front with fainter extension toward S 
			followed by several ragged loop fronts (in particular,
			at 09:06 UT). GOES recorded a C9.3 X-ray flare on NOAA 
			AR 0652 (N03E24) between 04:53 - 05:40 UT with peak
			emission at 05:21 UT. EIT Fe XII running difference 
			images show a brightening on AR 0652 starting at 05:00
			UT. Material is seen to be ejected mainly toward SW. 
			Another brightening at 08:00 UT.

10:54 UT  N East	Very faint and narrow loop front.