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

"We are not saying that all ultrahigh-energy cosmic rays are ultraheavy nuclei. But if some of the highest-energy events are ultraheavy nuclei, that would impact how we search for their sources."

From Science Daily ● Jun. 9, 2026

That makes it one of the most energetic cosmic rays ever detected.

From Science Daily ● Jun. 9, 2026

The findings mark an important advance in understanding how cosmic rays are created and how they travel through the galaxy.

From Science Daily ● May 14, 2026

A photography student at a university has created unique works of art using cosmic rays high above the earth.

From BBC ● Apr. 29, 2026

This query bore the unmistakable fingerprints of Arthur Compton, who reigned as the world’s leading expert on cosmic rays.

From "Big Science" by Michael Hiltzik