right ascension
noun
: 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
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This means that when viewed from Earth the two bodies share the same right ascension, which is the astronomical equivalent of longitude in the sky.
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Samantha Mathewson, Space.com, 17 Jan. 2025
First, on January 19, Venus and Saturn will experience a conjunction and share the same right ascension, appearing as close neighbors in the night sky.
—Jack Knudson, Discover Magazine, 14 Jan. 2025
Declination and right ascension are the two primary axes of the celestial sphere.
—Reece Rogers, WIRED, 21 Dec. 2022
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Samantha Mathewson, Space.com, 17 Jan. 2025
First, on January 19, Venus and Saturn will experience a conjunction and share the same right ascension, appearing as close neighbors in the night sky.
—Jack Knudson, Discover Magazine, 14 Jan. 2025
Declination and right ascension are the two primary axes of the celestial sphere.
—Reece Rogers, WIRED, 21 Dec. 2022
Cite this Entry
“Right ascension.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/right%20ascension. Accessed 31 Oct. 2025.
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