December 3, 2012
Solar Back-sided Halo CME
The Sun erupted with several CMEs (coronal mass ejections) during a period just over a day (Nov. 8-9, 2012), the largest of which was a halo CME. This CME appears to have originated from an active region barely out of view on the left side of the Sun and was headed behind the Sun. A halo CME is one where the ejected material appears to form a roughly circular shape around the Sun, not because it surrounds the Sun but because it is moving directly toward or away from the observer. These images combine SDO’s video of the Sun in extreme UV light superimposed on a view of the corona from SOHO’s LASCO instrument.