LASCO Activity Report for
May 24, 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

LASCO participated in the coronal holes/streamer boundary study of
UVCS/SUMER/CDS during May 17th through 23rd. It introduced only slight
modifications to the LASCO synoptic observation plan:

For C2: 6 hr cadence in orange filter pB (02:54 - 08:54 - 14:45 - 20:54 UT)
For C3: 12 hr cadence in orange filter pB (10:42 - 22:42 UT)

Now, again Nominal.


SOHO Telemetry Submode changed to Submode 5 on 2004/04/13 at 16:00 UT 
(SUMER began observing on 2004/04/14). SUMER campaign runs until 2004/06/17.
In other words, LASCO synoptic observation plan cadence remains the same
but the EIT CME watch images will be reduced to half-resolution (512x512)
during that period.

2004/05/21 (Friday)

05:50 UT  WN West	Asymmetric loop front in the trailing material (southern
			leg) of event reported to start at 23:26 UT on previous
			day. It fades close to the inner edge of C3.

12:26 UT  N East	Narrow and faint ragged front. It fades throughout C2.

18:50 UT  N Pole	Extemely faint loop front, developing slightly toward 
			NNE. It fades throughout C3.

19:27 UT  ES East	Faint ragged front. It fades throughout C3.
	

2004/05/22 (Saturday)

00:26 UT  ES East	Ragged spray-like front that fades throughout C2.

01:27 UT  N East	Another narrow and faint ragged front that fades
			throughout C3.

04:26 UT  N West	Ragged and diffuse loop front. It fades close to the
			inner edge of C3.
 
06:50 UT  S West	Very faint (though wide) loop front, barely visible in
			C3. At 07:27 UT a bright and narrow fan-like front
			develops. It fades close to the inner edge of C3.

2004/05/23 (Sunday)

11:06 UT  W Limb	Bright and wide ragged loop front. By 12:50 UT faint
			extensions surround completely the C2 occultor. The
			event is first seen in C3 at 11:42 UT, the C3 occultor 
			being completely covered by 15:18 UT. EIT Fe XII running
			difference images show a huge signature of a backsided
			CME above the W Limb starting at 11:00 UT. Material
			is swept away toward N and S as the event develops. The
			event has therefore been determined as a 'full' 
			(asymmetric) halo CME, backsided. 

15:26 UT  ES East	Very faint asymmetric loop front.

15:50 UT  W Limb	Diffuse and ragged loop front with apparently twisted
			trailing material. By 16:26 UT a diffuse loop front
			starts developing to S. They both fade throughout C3.

2004/05/24 (Monday)

05:06 UT  W Limb	Very narrow ragged front.

07:27 UT  S East	Ragged loop front.

	12:10 - 20:15 UT	Temporary DSN Data Gap.