1. [ noun ] (astronomy) the angular distance eastward along the celestial equator from the vernal equinox to the intersection of the hour circle that passes through the body; expressed in hours minutes and second
Synonyms: celestial_longitude RA

"one hour of right ascension equals fifteen degrees"

Related terms: angular_distance astronomy
2. [ noun ] (geography) an arc of the celestial equator eastward from the vernal equinox
Related terms: celestial_equator