UCMEO 93001 31215 0330/ 31213 60000 80442 1451/ 354// 112// 30398 31213 62229 80029 40625 13514 1212/ 99999 PLAIN SOHO/LASCO HALO CME December 13, 2023 C2 Start Time: 00:00 UT C3 Start Time: 00:30 UT Type of CME: Asymmetric HALO CME — FRONTSIDE pa1: 145 pa2: 354 Total Width: 209 degrees Velocity Measurements: C2: 8 points 412.3 km/sec @ PA 288.46 C3: 8 points 400.6 km/sec @ PA 288.59 Average through both(C2/C3) fields: 398.6 km/sec Acceleration: -3.77 m/sec^2 COMMENT: LASCO C2/C3 show a very faint partial halo CME. The CME emerges from the W and propagates outward in that direction. The partial halo CMEs source is a C2.9 flare centered on N06W25(3514) .A double ribbon flare/surface brightening is observed in the region best seen in SDO AIA 304, along with post-eruptive arcade. NOAA/GOES reports a C2.9 flare from AR 13514 22:29/22:55/00:29 UT STEREO Beacon Data COR2 A, shows a partial halo CME emerging from W, starting between 00:53 - 1:23UT. Preliminary time/height measurements gives a velocity of 364.2 km/sec @ PA 283.55 using 4 points of measurement. 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/2023/231213 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