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

They can be produced when cosmic-ray particles interact with their surroundings, and their energies are typically about one-tenth of the energy carried by the cosmic rays that created them.

From Science Daily ● Aug. 2, 2026

New research led by scientists at Penn State and published in Physical Review Letters suggests that some of the highest-energy cosmic rays may be atomic nuclei heavier than iron.

From Science Daily ● Jun. 9, 2026

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

But thus far they had been detected only in cosmic rays; the possibility of a laboratory demonstration of their existence might well justify construction of the cyclotron that could achieve it.

From "Big Science" by Michael Hiltzik