LASCO Activity Report for
August 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

2004/08/16 (Monday)

00:30 UT  S West	Relatively narrow loop-like feature with a faint and
			diffuse expanding (and wider) loop front ahead. By
			06:30 UT becomes discernible an inner structure
			in the form of a narrower loop front with a bright top.
 
06:06 UT  ES East	Faint and small loop front that quickly fades.

12:30 UT  WN West	Bright loop front and twisted inner material followed 
			later by much gusty outflow. By 12:54 UT extremely 
			faint extensions begin to be visible above the N Pole. 
			By 14:30, barely N of the northern leg of the loop
			feature, a faint expanding front seems to develop. The
			loop structure is first seen in C3 at 13:42 UT above 
			the WNW Limb. By 16:18 UT extremely faint extensions
			already surround the occultor. The mean plane-of-sky
			speed for the LE of the loop front at PA ~ 286 was ~ 
			550 km/sec (based only on C3 data). Starting at 
			11:48 UT, EIT Fe XII running difference images show 
			signatures of a CME originated, at most, a few days
			behind the limb, and developing above the WNW Limb 
			(most likely the C2 loop front counterpart). Between
			12:00 and 12:12 UT inner material begins to be seen 
			(most likely counterpart of the twisted inner material
			seen in C2). Also by 12:12, a faint and diffuse loop
			arise and seems to develop with a different angle 
			respect to the plane of sky than that of the loop front.
			Globally, the event could therefore be determined as a
			very asymmetric and faint 'full' halo CME, backsided. 
			However, given the apparent origin of the event, an
			Earthside component cannot be disregarded.

16:06 UT  N west	Small ragged fronts in the trailing material of the 
			loop front at 12:30 UT (northern leg). In particular at
			around: 16:06, 17:54, 18:54, and 20:54 UT.

18:30 UT  WN West	Elongated loop front becomes visible in the trailing
			material of the loop front at 12:30 UT (southern leg).
			It is followed by a similar one at 20:06 UT.

2004/08/17 (Tuesday)

	  WN West	Gusty outflow and small ragged fronts continue.

	  WS West	Gusty outflow continues.
	
06:06 UT  S East	Bright loop front with cavity and twisted inner core. 
			Faint extensions to N by 08:30 UT.