LASCO Activity Report for
May 17, 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 will be participating with the streamers study of UVCS/SUMER/CDS
during May 17th through 23rd. It introduces 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)


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.

2004/05/14 (Friday)

00:06 UT  E Limb	Faint loop front that is brighter above the ESE Limb, 
			most likely because it superposes in the LOS with a
			preceding (fainter) elongated loop-like structure. It 
			is difficult to give an exact time of first appearance
			(feature lost at the beginning in the trailing material
			of previous event). Not discernible in C3.

03:06 UT  E Limb	Small ragged front. It fades throughout C2.

03:50 UT  N East	Diffuse front develops as a faint asymmetric loop-like
			feature, followed at 08:26 by a brighter narrow front 
			at roughly the PA of the northern leg (along streamer).
			Another ragged front by ~ 14:06 UT.

08:26 UT  E Limb	Bright elongated feature. EIT Fe XII running difference 
			images show a bright barely backsided CME starting at
			07:48 UT.

23:37 UT  S East	Very faint loop front. It faints very close to the 
			inner edge of C3 FOV.
			 

2004/05/15 (Saturday)

02:26 UT  ES East	Ragged fan-like front that precedes a ragged front at
			05:26 UT above the E limb, and a diffuse and ragged loop
			front at ~06:50 UT on the ESE Limb that fades troughout
			C2.		

04:06 UT  WS West	Bright loop front with twisted inner core. By ~06:50 UT
			a small and fainter ragged front appears ahead of the 
			southern part of the LE of the bright loop front
			developing apparently faster.

08:26 UT  N East	Kind of gusty outflow developing towards NNE, superposed
			in the LOS with an initially slowly-evolving system of
			loops.

13:27 UT  E Limb	Faint and wide loop front brighter above the SE Limb.
			Very faint in C3, and only close to the inner edge. By
			~ 16:06 UT a ragged narrow front appears above the E
			Limb. It is 'pushed' toward N as it develops.

16:26 UT  W Limb	Bright ragged loop front, cavity, and bright twisted
			inner core. It appears at roughly the PA of the northern
			leg of the event reported to start at 04:06 UT.
 
20:50 UT  E Limb 	Another faint and wide loop front brighter above the 
			SE Limb. By ~22:26 UT a small ragged front develops 
			above the E Limb and quickly fades.

2004/05/16 (Sunday)

01:27 UT  E Limb	Bright and elongated loop front. It fades throughout C3.

02:26 UT  ES East	Fast fan-like front preceding a very faint loop front at
			~05:26 UT, that quickly fades.

02:26 UT  N West	Small ragged front. Barely visible in C3.

06:50 UT  W Limb	Extremely faint ragged loop front in the trailing 
			twisted structure of event reported to start at 16:26 UT
			on previous day.

12:50 UT  WS West	Small blob-like front. Difficult to establish the exact
			time of first appearance. Gusty outflow.

2004/05/17 (Monday)

05:26 UT  W Limb	Bright ragged loop front and trailing material. Very
			faint and diffuse envelope surrounds the front.

05:50 UT  N East	Kind of 'reconexion' event. Structure flowing out and
			another one falling down. Separation point at ~ 3.8
			solar radii (PA ~ 55 deg).
		
06:50 UT  S East	Fast narrow and ragged (diffuse) loop front.