cosmic rays

British  

plural noun

1. Also called: cosmic radiation.  radiation consisting of particles, esp protons, of very high energy that reach the earth from outer space

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cosmic rays Cultural  

1. Elementary particles, mainly protons, that are produced by the sun and other stars and then strike the upper atmosphere of the Earth. Some of these particles are absorbed, some help form the Van Allen belt, and some reach the Earth's surface, where they form a part of the background radiation that constantly surrounds us.

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Example Sentences

See Examples For:

cosmic rays

Dr Sharman said during the mission she was affected by radiation from outside the solar system, called galactic cosmic rays.

From BBC ● Aug. 28, 2026

The darker streaks contain surface dust and rocks that have been altered over long periods by solar wind, galactic cosmic rays, and impacts from micrometeorites.

From Science Daily ● Aug. 20, 2026

"This immense energy makes cosmic rays important in astronomy and astrophysics," said first and corresponding author of the study Tsunefumi Mizuno, associate professor at Hiroshima University's Hiroshima Astrophysical Science Center.

From Science Daily ● Aug. 2, 2026

Ultrahigh-energy cosmic rays are particles from space that slam into Earth with energies far beyond anything produced by human-built particle accelerators.

From Science Daily ● Jun. 9, 2026

“I think the phenomena in the cosmic rays point the way to us,” he wrote.

From "Big Science" by Michael Hiltzik