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CME SCORE Classification System

SCORE indicates the type of the detected CME based on the transient speed (see PDF chart). Typification is based on the rate of occurrence of CMEs and thus gives the user a quick idea about the likelihood of the observed event.

The different SCORE CME types are:
S-type: CMEs with speeds less than 500 km/s
C-type: Common 500-999 km/s
O-type: Occasional 1000-1999 km/s
R-type: Rare 2000-2999 km/s
ER-type: Extremely Rare >3000 km/s

Evans, R. M., A. A. Pulkkinen, Y. Zheng, M. Leila Mays, A. Taktakishvili, M. M. Kuznetsova, and M. Hesse (2013), The SCORE Scale: A Coronal Mass Ejection Typification System Based On Speed, Space Weather, 11, doi:10.1002/swe.20058.

View a video describing SCORE: