annual variation


Definition of annual variation

: the yearly change in a star's mean right ascension or declination produced by precession of the equinoxes and proper motion of the star

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First Known Use of annual variation

1760, in the meaning defined above

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The first known use of annual variation was in 1760

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Cite this Entry

“Annual variation.” Dictionary, Merriam-Webster, Accessed 28 Jan. 2021.

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