Definition of plasmasphere

: a region of a planet's atmosphere containing electrons and highly ionized particles that rotate with the planet

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First Known Use of plasmasphere

1966, in the meaning defined above

History and Etymology for plasmasphere

plasma + sphere

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The first known use of plasmasphere was in 1966

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Cite this Entry

“Plasmasphere.” Dictionary, Merriam-Webster, Accessed 25 Oct. 2020.

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