coronal mass ejection

noun Astronomy.
  1. a large-scale solar event involving an ejection of hot plasma that may accelerate charged particles and travel as far as the earth's orbit, preceded by a shock front that may create a magnetic storm on earth. Abbreviation: CME
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British Dictionary definitions for coronal mass ejection

coronal mass ejection

noun
  1. a cloud of particles ejected from the sun's surface during a solar flare
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

coronal mass ejection in Science

coronal mass ejection

[kôrə-nəl, kŏr-, kə-rōnəl]
  1. A massive, bubble-shaped burst of plasma expanding outward from the Sun's corona, in which large amounts of superheated particles are emitted at nearly the speed of light. The emissions can cause disturbances in the solar wind that disrupt satellites and create powerful magnetic storms on Earth. They were first observed in the early 1970s, when photographs taken from satellites revealed coronal activity that could not be seen in images taken from Earth.
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