Halo CME Mail

Date: Wed, 27 Aug 2003 16:53

From: Gareth Lawrence

Subject: Partial Halo CME on 2003/08/25, probably frontsided

Status: O

UCMEO 93001 30827 2115/
30825 60127 92142 1001/ 140// 223// 40308
30825 60212 80300 24111 10442 1112/

LASCO/EIT observed a wide partial halo CME on 2003/08/25. The 
event was first observed in C2 data at 01:27 UT as a system
of faint loop fronts rising along a streamer in the SW; this 
front spanned 140 deg from PA 100 - PA 240 by 03:06 UT. The 
front first appeared in C3 at 09:18 UT with maximal coverage 
of the C3 occultor by 19:00 UT. The mean plane-of-sky speed 
for this event was 308 km/s at PA 185, with moderate 

EIT observed an C3.6 X-ray flare between 02:12 - 03:00 UT with
peak emission at 02:36 UT. The source of the flare was AR 0442
centered on S11E41. A separate CME probably associated with 
this flare can be seen in LASCO images along the streamer in 
the SE from 03:26 UT; afterwards the slow fronts in the SW 
appear to span over the S pole and to the vicinity of this 
streamer. Note that the faint fronts had been visible in the SW 
for a considerable time prior to the flare in the SE. A modest 
EIT wave and dimming were observed in association with this event, 
primarily to the W of the AR. This event has therefore been 
determined probably frontsided.

Movies and images of this event will shortly available at: 

Best wishes,
        Gareth Lawrence.

+----------PLEASE NOTE NEW EMAIL ADDRESS-----------+
Gareth Lawrence,           grl@grace.nascom.nasa.gov 
SOHO-LASCO Operations Scientist,                                           
CUA, MC 682.3, Bldg 26, Rm 001,   F: +1-301-286-0264         
NASA Goddard Space Flight Center,
Greenbelt, MD 20771.              P: +1-301-286-2941