Right_ascensionWordNet Explorer

(astronomy) the equatorial coordinate specifying the angle, measured eastward along the celestial equator, from the vernal equinox to the intersection of the hour circle that passes through an object in the sky; usually expressed in hours and minutes and seconds; used with declination to specify positions on the celestial sphere

the angular separation between two objects as perceived by an observer

the branch of physics that studies celestial bodies and the universe as a whole