Subject: SOHO/LASCO HALO CME 140225

UCMEO 93001 40225 1330/
40225 70125 80354 1011/ 100// 31827
40225 60042 80106 28212 11990 1112/
99999

PLAIN

SOHO/LASCO observed an asymmetric HALO CME on February 25, 2014.  Event is first
seen in C2 at 01:25 UT in progress in first frame with the leading edge
of the CME out of the field of view. The event expands with extensions to
a full halo by 01:48 UT. The event continues into the C3 field beginning 01:30
to 03:54 UT at 30Rsun. Increased proton flux is evident in the Lasco images. 

The event is measured in the C3 field at 7 points with speeds od 1827.3 km/sec
at position 101 degrees.


SDO/AIA 193 shows a flare 00:42-01:06 UT at location [S12, E82 ]
from AR11990 near the East limb with emission.  A global dimming and wave
is seen across the disk.

STEREO: BEACON Data
COR2 A, 00:00-05:45 UT data gap. 
EUVI A, 00:00-05:30 UT data gap. 
COR2 B, 00:55 UT begins a bright loop over the West. Only 1 frame before gap.   
EUVI B, 00:46 shows a flare over the West limb. Only frame before gap.

NOAA reports a X4.9 class Xray flare 00:39/00:49/01:03 UT from AR 11990
at location [S12, E82].  An increase of proton flux is reported >=100 MeV
levels with flux 10 Mev levels at storm conditions.

The observation of this event is 'FAIR'. 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/2014/140225/

Best regards,

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

BT