cosmic ray
Definition of cosmic ray
: a stream of atomic nuclei of extremely penetrating character that enter the earth's atmosphere from outer space at speeds approaching that of light
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First Known Use of cosmic ray
1925
COSMIC RAY Defined for English Language Learners
cosmic ray
Definition of cosmic ray for English Language Learners
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: a stream of energy that enters the Earth's atmosphere from outer space
COSMIC RAY Defined for Kids
cosmic ray
Definition of cosmic ray for Students
: a stream of very penetrating particles that enter the earth's atmosphere from outer space at high speed
Learn More about cosmic ray
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See words that rhyme with cosmic ray Britannica.com: Encyclopedia article about cosmic ray
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