Subject: Full Halo CME on 2003/11/04, frontsided

From: Gareth Lawrence <[email-masked]>
Date: Tue, 4 Nov 2003 17:15:50 -0500 (EST)

UCMEO 93001 31104 2130/
31104 61954 82042 0001/ 360// 233// 42381
31104 61936 92012 38822 10486 1111/
99999

PLAIN

BT

LASCO and EIT observed a full halo CME on 2003/11/04.
The event was first observed in C2 at 19:54 UT as a bright
loop front in the SE; by 20:06 UT the front had developed 
into a full halo CME, though rather faint in the NE.
The front first appeared in C3 images at 20:18 UT with 
full coverage of the C3 occulting disk by 20:42 UT. The 
mean plane-of-sky speed for this event was 2381 km/s at 
PA 247; there is possible evidence for moderate acceleration
though at the time of writing only four data point are 
available so this may be an artefact of the sparse data. 

The CME was probably associated with an X18+ X-ray flare
observed by EIT between 19:36 - 20:12 UT, centered at
S22W88 with peak emission at 19:48 UT. GOES records this
flare from AR 0486 between 19:29 - 20:07 UT with a
prolonged saturated peak between ~19:40 - ~19:55 UT. 
A 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:

ftp://ares.nrl.navy.mil/pub/lasco/halo/20031104

and the EIT movies in particular are truly spectacular!

Best wishes,
        Gareth Lawrence.

+----------PLEASE NOTE NEW EMAIL ADDRESS-----------+
Gareth Lawrence,           [email-masked] 
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
+--------------------------------------------------+