Halo CME Mail

Date: Wed, 17 Apr 2002 18:09:55 +0000 (GMT)

From: Kevin Schenk

Subject: Full HALO CME of 2002/04/17


Status: O

UCMEO 93001 20417 1600/
20417 60826 91242 2661/ 265// 123// 41192
20417 60748 80948 31537 09906 1112/
99999

BT

EIT and LASCO observed a FULL HALO CME event on 2002/04/17.  The event
first seen in C2 begining 08:26 as a large loop front with cavity over the
West hemisphere.  This event quickly developed to a full HALO event.  The
LE was first seen in the C3 field beginning 08:42 UT and tracked to 28 Rs
by 12:42 UT. The speeds were determined at two position angles to limit
the acceleration from what was discovered to be two separate ejections. 
The plane-of-sky speeds averaged through both fields at PA 266; 1191
km/sec and at PA 106; 600 km/sec. Minor increase of visible protons are
seen in the white light images.

EIT observed a limb CME from AR 9905 at location [S15; W83] and a flare of
AR 9906 at location [S15; W37] beginning 2002/04/17 at 07:46 UT.  The
flare produced a region dimming with Northward wave and bright post event
loop arcade.  GOES shows a long duration M2.3 x-ray flare event during
this time range.  These events are probably related to the events seen in
Lasco.

Images and movies are available on the Lasco FTP server at:

ftp://ares.nrl.navy.mil/pub/lasco/halo/20020417/

note: we have have been notified of download restrictions with the use of
different browser configurations.  We appologize in advance and are
working to correct this.  This has been seen in older versions of IE and
Netscape.

Best

Kevin Schenk
EIT and LASCO Operations
NASA-Goddard Space Flight Cent