SOHO/LASCO Partial HALO CME 130521 BACKSIDED

UCMEO 93001 30521 1650/
30521 60224 90718 0862/ 267// 223// 20645
30521 70245 8//// ///// ///// ///2/
99999

PLAIN

SOHO/LASCO observed a partial HALO CME on May 21, 2013.  Event is first seen in
C2 beginning 02:24 UT with a slow multi-loop over the South.  The event expands
with extensions PA 86 - 267 for a total width of 181 degrees wide.  The event
continues into the C3 field beginning 03:06-07:418 UT still in progress at 
last frame before a DSN data gap period.

Time/height measurements were marked at 4 points in C2 with speeds of
624.4 Km/sec at pa 165 degrees. The event is marked to 11 points in C3.  
Speeds average through both fields to 645.5 Km/sec at PA 165 degrees.
Acceleration -19.74 m/sec^2. 

SDO AIA, n/a 

STEREO: BEACON data
COR2 A,  00:00-03:24 UT data gap. In progress at first frame, expanding
asymmetric halo over the South.
Preliminary time/height measure gives 643.7 km/sec velocity at LE.
EUVI A 195, 16:35-02:45 UT data gap. Loop arcade in progress from region
on the limb in the SW.
COR2 B, 00:00-04:54 UT data gap. In progress at first frame, expanding 
burst over the Southeast and South hemispheres.
Preliminary time/height measure gives 903.3 km/sec velocity at LE.
EUVI B 195, 19:45-04:45 UT data gap.  AR near central meridian in South
in progress with post loop arcade located [S25, E148].

The observation of this event is considered 'POOR'. This CME is determined BACKSIDED.

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

http://umbra.nascom.nasa.gov/lasco/observations/halo/2013/130521/

Best regards,

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

BT