UCMEO 93001 40101 1600/
31231 62148 80054 0001/ 215// 133// 32427
31231 62136 82213 10479 13536 1112/
99999

PLAIN   


SOHO/LASCO  HALO CME December 31, 2023 

C2 Start Time: 21:48 - 22:00 UT

C3 Start Time: 21:54 - 22:18 UT

Type of CME:
Asymmetric HALO CME — FRONTSIDE
pa1:  000    pa2:  215       Total Width:  215 degrees

Velocity Measurements:

C2:   1 point     *** km/sec @ PA 95.59
C3:   5 points   2355.8 km/sec @ PA 95.34
Average through both(C2/C3) fields:  2427.2 km/sec  Acceleration: -51.76 m/sec^2

COMMENT:  LASCO C2/C3  show a very fast moving partial halo CME, emerging directly from the east. In C3 imagery, the CME appears at 22:18 UT and quickly envelops the whole east side by 23:06 UT.  The CME propagates outwards prmarily in the east direction and mostly dissipates by 01:00 UT. The source is associated with a X5.0 flare centered on N04E79(AR 3536) on the east limb. In SDO AIA 193 , an EUV wave can be seen following the flare moving west along the disk. Opening field lines can also be seen behind the east limb in AIA 193 starting at 21:42 UT.

NOAA/GOES reports a X5.0 flare from AR 13536 21:36/21:55/22:13 UT

STEREO Beacon Data COR2 A, due to gaps in data from 18:53 - 00:53 UT, preliminary time/height measurements could not be performed at this time.

Preliminary UCMEO velocity and position measurements are delivered first.
Images, movies, and time/height information for this event will be available at:

https://umbra.nascom.nasa.gov/lasco/observations/halo/2023/231231



Best Regards,

--James Tabourne

BT
[Images from original message are omitted here]

________________________________________________
Soho-halo-alert mailing list
Soho-halo-alert@mail.nascom.nasa.gov
https://mail.nascom.nasa.gov/mailman/listinfo/soho-halo-alert