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

Examples of right ascension in a Sentence

Recent Examples on the Web Declination and right ascension are the two primary axes of the celestial sphere. Reece Rogers, Wired, 19 Dec. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'right ascension.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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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right ascension

right at

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Cite this Entry

“Right ascension.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/right%20ascension. Accessed 28 Sep. 2022.

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More from Merriam-Webster on right ascension

Britannica.com: Encyclopedia article about right ascension


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