The intersection of the plane in of the ecliptic with the celestial equator This intersection occurs once a year, at the moment the Sun crosses the celestial equator moving from south to north
The place on the celestial sphere where the sun crosses the celestial equator moving northward; also, the time of year when the sun crosses this point, about March 21, and Spring begins in the Northern hemisphere
Taking place in the Northern Hemispheric spring, it is the point at which the ecliptic intersects the celestial equator Days and nights are most nearly equal in duration It falls on or about March 20 and is considered the beginning of spring in the Northern Hemisphere and autumn in the Southern Hemisphere It is the astronomical opposite of the autumnal equinox
The spring equinox The term is also used for the point occupied by the Sun at that time, one of the two intersections on the celestial spher, between the ecliptic and the celestial equator Also known as first point in Aries
The point of intersection between the ecliptic and the celestial equator, where the Sun crosses from south to north By definition, the zero point of right ascension Known as the First Point of Aries, it is now in the constellation Pisces, due to precession of the equinoxes Also, the time (near March 21) at which the Sun makes its northward crossing of the celestial equator Currently migrating toward March 19, due to precession
The point on the celestial sphere where the sun crosses the celestial equator moving northward, which corresponds to the beginning of spring in the northern hemisphere and the beginning of autumn in the southern hemisphere (in the third week of March) This point corresponds to zero (0) hours of right ascension