coronal mass ejection
noun
: a tremendous outburst of energy from the corona of the sun that can cause disruptions in the earth's geomagnetic field
As they had for the January eruption, the researchers relied on an armada of spacecraft to track the disturbance, known as a coronal mass ejection because it originates in the sun's outer atmosphere, or corona.—
Ron Cowen
—abbreviation CME
compare solar flare
Ron CowenExamples of coronal mass ejection in a Sentence
Recent Examples on the Web
The peak of this solar cycle — called solar maximum — is when sunspots, solar flares and coronal mass ejections (CMEs) are the most frequent.
—Ryan French, Space.com, 18 Dec. 2025
The dramatic expansion of the northern lights was caused by intense activity on the sun including multiple solar eruptions known as coronal mass ejections.
—Jeffrey Kluger, Time, 18 Dec. 2025
Over the weekend, scientists with NOAA's Space Weather Prediction Center caught a powerful coronal mass ejection (CME) expected to collide with Earth's upper atmosphere sometime Monday.
—John Tufts, IndyStar, 8 Dec. 2025
Such activity, also known as space weather events, can include eruptions of high-energy light called solar flares, as well as coronal mass ejections, which are giant blobs of solar plasma and magnetic field blasted into space.
—Meghan Bartels, Scientific American, 19 Nov. 2025
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Ryan French, Space.com, 18 Dec. 2025
The dramatic expansion of the northern lights was caused by intense activity on the sun including multiple solar eruptions known as coronal mass ejections.
—Jeffrey Kluger, Time, 18 Dec. 2025
Over the weekend, scientists with NOAA's Space Weather Prediction Center caught a powerful coronal mass ejection (CME) expected to collide with Earth's upper atmosphere sometime Monday.
—John Tufts, IndyStar, 8 Dec. 2025
Such activity, also known as space weather events, can include eruptions of high-energy light called solar flares, as well as coronal mass ejections, which are giant blobs of solar plasma and magnetic field blasted into space.
—Meghan Bartels, Scientific American, 19 Nov. 2025
See All Example Sentences for coronal mass ejection
Cite this Entry
“Coronal mass ejection.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/coronal%20mass%20ejection. Accessed 24 Dec. 2025.
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