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 shockingly, some cosmic rays have far, far higher energies than this.
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Phil Plait, Scientific American, 3 Apr. 2026
Going beyond Earth’s orbit comes with a host of risks, such as the sheer distance from home if anything goes awry, and the health effects of exposure to deep-space radiation from solar activity or cosmic rays once the astronauts are beyond the protection of Earth’s magnetic field.
—Carolyn Y. Johnson, Washington Post, 2 Apr. 2026
This includes discovering the effect of high-speed particles called cosmic rays on the winds of the galaxy.
—Robert Lea, Space.com, 31 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
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Phil Plait, Scientific American, 3 Apr. 2026
Going beyond Earth’s orbit comes with a host of risks, such as the sheer distance from home if anything goes awry, and the health effects of exposure to deep-space radiation from solar activity or cosmic rays once the astronauts are beyond the protection of Earth’s magnetic field.
—Carolyn Y. Johnson, Washington Post, 2 Apr. 2026
This includes discovering the effect of high-speed particles called cosmic rays on the winds of the galaxy.
—Robert Lea, Space.com, 31 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
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 11 Apr. 2026.
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