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

Once in orbit, the chip will have to survive being bombarded by cosmic rays and solar events.

From The Wall Street Journal ● Oct. 1, 2026

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 discovery could help researchers better understand cosmic rays, the extremely fast particles that travel through the space between stars and affect events throughout the galaxy.

From Science Daily ● Aug. 2, 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

Libby’s research began in the global scientific race during the 1930s and 1940s to understand cosmic rays, the mysterious, ultrahigh- velocity subatomic particles that continually rain onto the earth from outer space.

From "1491" by Charles C. Mann