Subject: SOHO/LASCO HALO CME 110215

UCMEO 93001 10215 1800/
10215 60236 81130 2111/ 210// 323// 40748
10215 60148 80154 31821 11158 1112/
99999

PLAIN

SOHO/LASCO observed a HALO CME on February 15, 2011.  Event is first seen in        
C2 at 02:36 UT as a full bright LE loop which encompassed the occulting disk and 
producing a symmetric full 360 degree HALO CME.  The event continues into the 
C3 field with material still surrounding the occulter beginning 03:06 to 11:30 UT out 
to approximately 25 Rsun as the event dissipates.

Time/height measurements were marked to 4 points in C2 with speeds of 788.5 Km/sec 
at position angle 213 degrees. The event is marked to 15 points in C3 where it 
slightly decelerates.  Speeds average through both fields to 747.8 Km/sec at PA 211 degrees.

SDO/AIA shows a bright flare of AR 11158 located at [S21, W18] on disk 
begining 01:48-01:54 UT.  This flare produced an almost global AIA wave.         
NOAA reports an X2.2 Xray flare of AR 11158 beginning at 01:44-01:56 UT. 
This is most probably the cause of the full HALO event seen in LASCO.
   
The observation of this event is considered 'GOOD'. This CME is determined a FRONTSIDED event.

Images and movies and time/height information for this event is available on the web at:

http://umbra.nascom.nasa.gov/lasco/observations/halo/2011/110215/

Best regards,

Kevin Schenk
Solar Heliospheric Observatory
EIT and LASCO Operations
NASA-Goddard Space Flight Center, USA

BT