UCMEO 93001 70918 1920/
70917 61200 81506 0742/ 073// 333// 41436
70917 61135 81255 ///// 12673 1112/
99999

PLAIN

SOHO/LASCO HALO CME September 17 2017

C2 Start Time:  	12:00 UT

C3 Start Time:		12:18 - 15:06 UT 

Type of CME:
Symmetric HALO CME — BACKSIDE
pa1:  74      pa2:  73       Total Width:  360 degrees

Velocity Measurements:

C2	3 points	1599 km/sec @ PA 74
C3	8 points	1408.4 km/sec @ PA 74
Average through both fields: 	1436 km/sec @ PA 74 Acceleration: -33.11 m/sec^2

STEREO-A COR2 12:24-14:24 UT Full HALO seen in COR2.
	04 points 1423.5 km/sec @ PA 95 Acceleration: 

COMMENT:   	STEREO AHEAD 195 BEACON data shows a flare on disk from 
			AR 12673 at location [S11, E169] at 11:35 - 12:55 UT. 
			 A dimming and an EUV wave is seen transitioning from 
			the East across the disk.

Preliminary UCMEO velocity and position measurements will be delivered first. 
Images, movies, and time/height information for this event will be available at:  
https://umbra.nascom.nasa.gov/lasco/observations/halo/2017/170917/


Best Regards

—Nick Padgett

BT