right ascension


Definition of right ascension

: the arc of the celestial equator between the vernal equinox and the point where the hour circle through a given body intersects the equator reckoned eastward commonly in terms of the corresponding interval of sidereal time in hours, minutes, and seconds

First Known Use of right ascension

15th century, in the meaning defined above

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The first known use of right ascension was in the 15th century

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