Van Allen radiation belt

noun

Van Al·​len radiation belt

va|ˈnalə̇n-,

və|

: 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

Word History

Etymology

after James A. Van Allen, born 1914 American physicist

First Known Use

1962, in the meaning defined above

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