Halo CME Mail

Date: Mon, 3 Feb 2003 17:11

From: Gareth Lawrence

Subject: Partial Halo CME on 2003/02/01, possibly fronsided

Status: O

UCMEO 93001 30203 2215/
30201 60939 90845 2551/ 040// 222// 40589
///// ///// ///// ///// ///// /////

LASCO observed a possible partial halo CME on 2003/02/01. The 
event was first observed in C2 at 01:51 UT as ragged loop 
front systems over the NW limb and N pole a significant way
into C2's field of view. The two systems appear distinct 
but there is insufficient data to rule out the possiblility
of a connection. The total span of the system is about
145 deg, from PA 255 - 40. These fronts first appeared in 
C3 at 02:20 UT but additionally with evidence of a leading
edge some way ahead of the NW limb fronts only. The mean 
plane-of-sky speed for the system was 589 km/s at PA 282, 
with insufficient data to infer acceleration, or lack
thereof. Only C3 data were used to measure this speed.

EIT had begun a routine CCD bakeout by this time, so no
on-disk EUV data are available. However, GOES recorded a
Type II radio burst from 22:09 UT on 2003/01/31 which
could have been associated with a frontsided source.
In light of the ambiguity in the data we conclude there
is a possibility that this event has an earthward-directed 

Movies and images of this event are available now at: 

Some people may experience difficulties obtaining the images and 
movies at present; this is due to unresolved issues with the 
firewall at NRL. Aplogies to those affected; the problem is being 
worked on.

Best wishes,
        Gareth Lawrence.

| Gareth Lawrence,                   E-mail:grl@kreutz.nascom.nasa.gov |
| SOHO-LASCO Operations Scientist,				       |
| CUA, Mail Code 682.3,                                                |
| NASA Goddard Space Flight Center,      Phone:  +1-301-286-2941       |
| Building 26, Room 001,                         +1-301-286-3447       |
| Greenbelt, MD 20771.                   Fax:    +1-301-286-0264       |