cosmic ray


Definition of cosmic ray

: 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

Recent Examples on the Web Correction: fixed an error regarding the average time between cosmic ray events. John Timmer, Ars Technica, 14 Dec. 2021 But cosmic ray energies, although the flux of the most energetic particles remains low, can reach to far greater values than any terrestrial accelerator. Ethan Siegel, Forbes, 10 Sep. 2021 Using cosmic ray events could help researchers study and date other historic sites thought to be Viking or medieval in origin, because there are at least two events that occurred during this period, in 775 and 993. Ashley Strickland, CNN, 20 Oct. 2021 Previous studies have established there was such a cosmic ray event in the year 993 that for a few months caused greater than usual levels of radioactive carbon-14 in the carbon dioxide of the atmosphere. NBC News, 20 Oct. 2021 So far, the instrument has detected over 180 billion cosmic ray events. Jennifer Leman, Popular Mechanics, 7 Oct. 2021 In 1970 scientists placed cosmic ray detectors in the lowest chamber in the Pyramid of Khafre. Edmund S. Higgins, The Conversation, 30 Sep. 2021 Piercing muonsParticle showers from cosmic ray strikes include muons (μ), heavy cousins of the electron that can penetrate animal tissue and lead to cancer. Daniel Clery, Science | AAAS, 15 July 2021 This would be the case for an energetic particle, like a cosmic ray, passing like a miniature projectile through our body. Avi Loeb, Scientific American, 6 June 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cosmic ray.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cosmic ray

1925, in the meaning defined above

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Time Traveler for cosmic ray

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The first known use of cosmic ray was in 1925

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Dictionary Entries Near cosmic ray

cosmic radiation

cosmic ray

cosmic-ray shower

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Statistics for cosmic ray

Last Updated

6 Jan 2022

Cite this Entry

“Cosmic ray.” Dictionary, Merriam-Webster, Accessed 25 Jan. 2022.

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More Definitions for cosmic ray

cosmic ray


English Language Learners Definition of cosmic ray

: a stream of energy that enters the Earth's atmosphere from outer space

cosmic ray


Kids Definition of cosmic ray

: a stream of very penetrating particles that enter the earth's atmosphere from outer space at high speed

More from Merriam-Webster on cosmic ray Encyclopedia article about cosmic ray


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