Van Allen radiation belt

Van Al·​len radiation belt | \ va|ˈnalə̇n-, və| \

Definition of Van Allen radiation belt

: a belt of intense ionizing radiation that surrounds the earth in the outer atmosphere, has particles carrying energies of from approximately 20,000 electron volts to several million electron volts or more, and has an outer zone that extends into space to a distance of about 55,000 kilometers

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First Known Use of Van Allen radiation belt

1962, in the meaning defined above

History and Etymology for Van Allen radiation belt

after James A. Van Allen, born 1914 American physicist

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The first known use of Van Allen radiation belt was in 1962

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Cite this Entry

“Van Allen radiation belt.” Dictionary, Merriam-Webster, Accessed 22 Jan. 2022.

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