SOHO/LASCO Halo CME 20120718

Halo Alert: halo-message.20120718

Subject: SOHO/LASCO HALO CME 120718 BACKSIDED

UCMEO 93001 20718 2030/
20718 60624 81330 3262/ 325// 123// 40711
20718 60554 80635 ///// ///// 1112/
99999

PLAIN

SOHO/LASCO observed a full HALO CME on July 18, 2012. Event is
first seen in C2 at 06:24 UT as a symmetric halo which appears
as a multi-part event. The event continues into the C3 field
beginning 06:54 to 13:30 UT leaving the C3 field at 30 Rsun.

Time/height measurements were marked to 7 points in C2 with speeds
of 713.2 Km/sec at position angle 326 degrees. The event is marked to 9 points
in C3. Speeds average through both fields to 711.2 Km/sec at PA 326 degrees.
Acceleration 2.96 m/sec^2.

SDO/AIA n/a

STEREO: Beacon data
COR2 A, 06:24 UT as a loop expanding over the west hemisphere. Appears as
a multiple event which almost form a halo.
Preliminary time/height measure gives 948.2 km/sec velocity at LE.
EUVI A, 05:54-06:35 UT flare from AR on disk at [N18,W180] with CME and wave.
COR2 B, 06:24 UT, bright loop expands to a full asymmetric halo (east).
Preliminary time/height measure gives 934.8 km/sec velocity at LE.
EUVI B, 05:55-06:35 UT, a flare from AR on limb with cme and wave over east.

The observation of this event is considered 'GOOD'. This CME is determined a BACKSIDED event.

Images and movies and time/height information for this event is available on the web at:

http://umbra.nascom.nasa.gov/lasco/observations/halo/2012/120718/

Best regards,

Kevin Schenk
Solar Heliospheric Observatory
EIT and LASCO Operations
NASA-Goddard Space Flight Center, USA

BT

SOHO/LASCO C2 Diff	SOHO/LASCO C3 Diff	STEREO/EUVI 195 AHEAD



STEREO/COR2 BEHIND	STEREO/EUVI 195 AHEAD	STEREO/COR2 AHEAD

Time/Height Velocities and Plots

C2/C3

Click on Links below for additional information.

Halo Alert: halo-message.20120718

MPEG Movies

LASCO Software IDL Save Files (.mvi)