cosmic ray
noun
: a stream of atomic nuclei of extremely penetrating character that enter the earth's atmosphere from outer space at speeds approaching that of light
Examples of cosmic ray in a Sentence
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But unlike the easily predictable radiation exposures from flying through the Van Allen Belts or basking in the background flux of galactic cosmic rays, the dose an astronaut gets from solar activity can vary enormously.
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Meghan Bartels, Scientific American, 31 Mar. 2026
But solar flares and coronal mass ejections (CMEs) — huge eruptions of solar plasma — could be a threat to Artemis astronauts venturing far beyond our planet, as could cosmic rays, which originate far beyond our solar system.
—Leonard David, Space.com, 30 Mar. 2026
The universe, however, consists of matter but almost no antimatter, which exists naturally only in small quantities, created by radioactive decay and cosmic ray collisions.
—Jacopo Prisco, CNN Money, 27 Mar. 2026
From cosmic ray experiments to radioactive decay experiments to solar experiments to high-energy physics experiments involving particle colliders, the Standard Model’s predictions have agreed with every single such experiment ever performed.
—Big Think, 24 Mar. 2026
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Meghan Bartels, Scientific American, 31 Mar. 2026
But solar flares and coronal mass ejections (CMEs) — huge eruptions of solar plasma — could be a threat to Artemis astronauts venturing far beyond our planet, as could cosmic rays, which originate far beyond our solar system.
—Leonard David, Space.com, 30 Mar. 2026
The universe, however, consists of matter but almost no antimatter, which exists naturally only in small quantities, created by radioactive decay and cosmic ray collisions.
—Jacopo Prisco, CNN Money, 27 Mar. 2026
From cosmic ray experiments to radioactive decay experiments to solar experiments to high-energy physics experiments involving particle colliders, the Standard Model’s predictions have agreed with every single such experiment ever performed.
—Big Think, 24 Mar. 2026
See All Example Sentences for cosmic ray
Cite this Entry
“Cosmic ray.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cosmic%20ray. Accessed 3 Apr. 2026.
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