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, 21 Dec. 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'right ascension.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

15th century, in the meaning defined above

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

Dictionary Entries Near right ascension

Cite this Entry

“Right ascension.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/right%20ascension. Accessed 30 Nov. 2023.

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