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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Its few dozen inhabitants study climate, sea ice, cosmic rays, meteorology, glaciology and biodiversity.
—
Jamie Carter, Space.com, 23 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
In contrast, many of the neutrinos detected on Earth are atmospheric neutrinos, produced by the impact of cosmic rays hitting atoms in Earth’s atmosphere, and are far less energetic.
—Jorge Garay, Wired News, 19 Aug. 2025
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Jamie Carter, Space.com, 23 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
In contrast, many of the neutrinos detected on Earth are atmospheric neutrinos, produced by the impact of cosmic rays hitting atoms in Earth’s atmosphere, and are far less energetic.
—Jorge Garay, Wired News, 19 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 29 Sep. 2025.
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