Subject: SOHO/LASCO HALO CME 100604 -BACKSIDED UCMEO 93001 00604 1530/ 00604 61206 91442 1902/ 147// 112// 30360 ///// ///// ///// ///// ///// 2222/ 99999 PLAIN SOHO/LASCO observed a partial HALO CME (type P) on June 4, 2010. Event began in C2 at 12:06 UT as an asymmetric loop front with core centered over PA 332 degrees. Material is seen from PA 190 - 147 degrees for a total coverage of 317 degrees wide. The event continues into the C3 field beginning at 13:42 UT. This event is in progress and at this time of writing only 3 frames in C3 are observed to 5.2 Rsun. The event is still progressing and may possibly spread to a full HALO CME event. Time/height measurements were marked to 5 points only in C2 and calculated to velocities of this event averaging 359.9. Km/sec at position angle 8 degrees. This event was not seen in EIT. STEREO B was checked but due to gap in coverage from 03:00 - 10:00 UT, it is not evident of the origination point. At this time this event is considered a BACKSIDED CME event. LASCO C2 images, movies and time/height information for this event is available on the web at: http://umbra.nascom.nasa.gov/lasco/observations/halo/2010/100604/ Best regards, Kevin Schenk SOHO Mission EIT and LASCO Operations NASA-Goddard Space Flight Center, USA BT