UCMEO 93001 30809 2300/ 30809 61600 81836 1242/ 316// 133// 30938 30809 ///// ///// ///// ///// ///// 99999 PLAIN SOHO/LASCO HALO CME August 9, 2023 C2 Start Time: 16:00UT C3 Start Time: 16:30 UT Type of CME: Asymmetric HALO CME — FRONTSIDE pa1: 124 pa2: 316 Total Width: 194 degrees Velocity Measurements: C2: 4 points 867.4 km/sec @ PA 258.55 C3: 12 points 941.1 km/sec @ PA 258.55 Average through both(C2/C3) fields: 938.0 km/sec Acceleration: 0.20 m/sec^2 COMMENT: LASCO C2/C3 show a partial halo CME emerging from the SW then propagates in the W/SW direction. The event is associated with a backsided eruption visible from beyond the NW limb as seen best in SDO AIA 171. STEREO Beacon Data COR2 A, shows a bright partial halo CME in the SW direction beginning at 16:23 UT. Preliminary time/height measurements gives a velocity of 1014.2 km/sec @ PA 253.53 using 6 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/2023/230809 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