Coronal mass ejections

Coronal mass ejection Expulsion of hot gas from a localized region in the solar corona into the interplanetary medium. 

Solar flares are one example of violent solar activity. The other important one is the episodic injection into the interplanetary medium of large masses of matter from the solar corona. In a so-called coronal mass ejection (CME) event, approximately 10 kg or more mass of ions can be expelled from the corona. Such coronal transients were first identified from data acquired during the Sky lab space station era of solar research in the mid-1970s, and their studies were continued with other missions such as the Solar Maximum Mission (SMM) in the 1980s. The launch of the Solar and Heliospheric Observatory (SOHO) spacecraft in the mid-1990s revolutionized the studies of the sun, and especially the phenomena of CMEs. 

Vourlidas, A., Davis, C.J., Eyles, C.J., Crothers, S.R., Harrison, R.A., Howard, R.A., Moses, J.D., Socker, D.G. First direct observation of the interaction between a comet and a coronal mass ejection leading to a complete plasma tail disconnection. Astrophys. J. Lett. 668, L79-... 

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