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

Additional theoretical work on cosmic explosions involving black holes and strongly magnetized neutron stars may also help reveal where ultrahigh-energy cosmic rays are born.

From Science Daily ● Jun. 9, 2026

"These highest-energy cosmic rays are thought to come from extreme astrophysical sources, like two neutron stars colliding or a massive star collapsing," Murase said.

From Science Daily ● Jun. 9, 2026

For more than 100 years, scientists have been trying to understand cosmic rays, incredibly powerful particles that travel across the universe at extreme energies.

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

The erosion in interstellar space—chiefly cosmic rays and impacting dust grains—is so slow that the information on the record will last a billion years.

From "Cosmos" by Carl Sagan