Halo CME Mail

Date: Mon, 13 Feb 2006 09:33

From: Guillermo Stenborg

Subject: Asymmetric Full Halo Event on 2006/02/10-11, backsided


Status: O

UCMEO 93001 60213 1435/
60210 62330 81542 0002/ 360// 123// 30465
60210 ///// ///// ///// ///// 5//2/
99999
 
PLAIN
 
BT 


LASCO/EIT observed a Full Halo Event on 2006/02/10-11. The event 
started to be seen in C2 on 2006/02/10 at 23:30 UT as a bright rim 
just appearing above the SE Limb. It develops as a bright, wide, 
and expanding loop front that practically covers the whole southern 
hemisphere in the C2 FOV early on 02/11. Very faint and diffuse 
extensions can be seen in the northern hemisphere, already fully 
covering the C2 occulting disk by 01:31 UT on 02/11 (the LE on S 
almost reached the end of the C2 FOV by that time).

The event is first seen in C3 on 2006/02/11 at 01:42 UT all above
the SE limb. The bulk of the CME develops mainly toward SSE. Faint 
extensions develops toward E and W, and fully surround the C3 occulting
disk by 04:18 UT (though by this time the diffuse extensions are barely
above the N Pole). The mean plane-of-sky speed of the LE of the event at
PA ~ 162 was ~ 465 km/sec, showing practically no acceleration.

GOES recorded no significant X-ray activity during 02/10 and 02/11 
(below the A level save an A3.6 X-ray flare on S19E81 between
22:53 - 23:08 UT with peak emission at 23:03 UT). Likewise EIT 195 
images do not show any significant event on the disk by the time 
prior to the LASCO C2 event. Note that a large and bright coronal 
loop system became visible on the east limb early on 02/11. The 
region may have been the source of the halo event.

In summary, the event has been determined as an asymmetric Full Halo
Event, backsided. And note that the bulk of the CME develops
mainly toward SSE as projected on the plane-of-sky.

Movies and images of the event will shortly be made available at: 

ftp://ares.nrl.navy.mil/pub/lasco/halo/20060210


Best wishes,

	Guillermo Stenborg


++
Dr. Guillermo A. Stenborg   
SOHO-LASCO Operations Scientist,                                           
CUA, MC 612.5, Bldg 26, Rm 001,   F: +1-301-286-0264         
NASA Goddard Space Flight Center,
Greenbelt, MD 20771.              P: +1-301-286-2941

e-mail: stenborg@kreutz.nascom.nasa.gov
+