Coronal mass ejection: S

Coronal Mass Ejections : An Introduction Angelos Vourlidas Naval Research Laboratory Contributions from R.A. Howard T. Zurbuchen Coronal Mass Ejections , or CMEs, are explosive bursts of solar plasma and magnetic field that fly away from the Sun at thousands of kilometers an hour. CMEs are frequently (but not always) associated with solar flares. Abstract. Coronal mass ejections (CMEs) are a key feature of coronal and interplanetary (IP) dynamics. Major CMEs inject large amounts of mass and magnetic fields into the heliosphere and, when aimed Earthward, can cause major geomagnetic storms and drive IP shocks, a key source of solar energetic particles. Studies over this solar cycle using the excellent data sets from the SOHO, TRACE, Yohkoh, Wind, ACE and other spacecraft and ground-based instruments have improved our knowledge of the ... CMEs travel outward from the Sun at speeds ranging from slower than 250 kilometers per second (km/s) to as fast as near 3000 km/s. The fastest Earth-directed CMEs can reach our planet in as little as 15-18 hours. Slower CMEs can take several days to arrive.