cosmic ray

American  

noun

Physics.

1. a radiation of high penetrating power that originates in outer space and consists partly of high-energy atomic nuclei.

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cosmic ray Scientific  

1. A ray of radiation of extraterrestrial origin, consisting of one or more charged particles such as protons, alpha particles, and larger atomic nuclei. Cosmic rays entering the atmosphere collide with atoms, producing secondary radiation, such as pions, muons, electrons, and gamma rays. Cosmic rays (and secondary radiation) can be easily seen in a cloud chamber.

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Etymology

Origin of cosmic ray

An Americanism dating back to 1920–25

Example Sentences

New work from astrophysicists at Michigan State University may help resolve a scientific question that has lingered for more than a century: where do galactic cosmic rays come from?

From Science Daily

Other theories propose that cosmic rays start the process because the charged particles they produce accelerate within existing electric fields.

From Science Daily

The lack of an atmosphere would mean no water and no protection from cosmic rays, said NASA’s Thomas Greene, the lead researcher.

From Seattle Times

"In this model, 'Oumuamua began as an icy planetesimal that was irradiated at low temperatures by cosmic rays during its interstellar journey, and experienced warming during its passage through the Solar System."

From Salon

Some researchers now hypothesize that supernova-generated particles known as cosmic rays might have depleted the ozone layer, increased cancer rates in ancient organisms, sparked wildfires, and even started an ice age.

From Science Magazine