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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Exposure to cosmic rays erodes the nitrogen ice, leaving behind water-ice objects that are likely more plentiful.
—
Nola Taylor Tillman, Space.com, 8 Sep. 2025
These particles, known as cosmic rays, are mostly composed of single protons, although heavier atomic nuclei, electrons, positrons (the antimatter counterpart of electrons), and neutrinos are all present as well.
—Ethan Siegel, Big Think, 4 Sep. 2025
For more than a century, scientists have known that Earth is constantly bombarded by cosmic rays, charged particles with staggering energies, far beyond what our accelerators can produce.
—Rupendra Brahambhatt, Interesting Engineering, 24 Aug. 2025
Life on these worlds would have to lurk underground for reasons other than thirst alone because their surface is scarcely shielded by an atmosphere and constantly bombarded with lethal cosmic rays.
—Emma R. Hasson, Scientific American, 17 Aug. 2025
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Nola Taylor Tillman, Space.com, 8 Sep. 2025
These particles, known as cosmic rays, are mostly composed of single protons, although heavier atomic nuclei, electrons, positrons (the antimatter counterpart of electrons), and neutrinos are all present as well.
—Ethan Siegel, Big Think, 4 Sep. 2025
For more than a century, scientists have known that Earth is constantly bombarded by cosmic rays, charged particles with staggering energies, far beyond what our accelerators can produce.
—Rupendra Brahambhatt, Interesting Engineering, 24 Aug. 2025
Life on these worlds would have to lurk underground for reasons other than thirst alone because their surface is scarcely shielded by an atmosphere and constantly bombarded with lethal cosmic rays.
—Emma R. Hasson, Scientific American, 17 Aug. 2025
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 15 Sep. 2025.
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