Halo CME Mail

Date: Mon, 27 Oct 2003 19:32

From: Gareth Lawrence

Subject: Partial Halo CME on 2003/10/26, frontsided

Status: O

UCMEO 93001 301027 2330/
31026 60654 91118 3251/ 215// 233// 41197
31026 60624 90800 24216 10486 1111/

LASCO and EIT observed a partial halo CME on 2003/10/26. 
The event was first observed in C2 at 06:54 UT as a bright 
loop front over the E limb; by 07:31 UT the front spanned
~250 deg from PA 325 - 215. The front first appeared in 
C3 images at 07:42 UT with maximal coverage of the C3 
occultor by 08:18 UT. Note that the emission in the W is
dominated by an earlier limb CME, and it is possible that 
the partial halo CME to the E could have a faint component
in the E. The mean plane-of-sky speed for this event was 
1197 km/s at PA 77, with possible evidence for modest

The CME was probably associated with an X1.2 X-ray flare
observed by EIT between 06:24 - 08:00 UT, centered at 
S16E42 with peak emission at 06:48 UT. GOES records this
flare from AR 0486 between 05:57 - 07:33 UT with peak 
emission at 06:54 UT. A very large EIT wave, and dimming,
were observed in association with this event. This event 
has therefore been determined frontsided.

Movies and images of this event will shortly be 
available at: 

and please note that a second halo CME report will
follow shortly after this one. 

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