Science / Astrology / Equinox: From the Latin aequinoctium, equal night; occurs when the center of the Sun is directly over Earth's equator. The Sun crosses the equator twice each year, once at the vernal equinox when it enters 0° Aries and again at the autumnal equinox when it enters 0° Libra. The days and nights are of equal duration all over the world on equinoctial dates. The vernal equinox occurs on the first day of spring, the autumnal equinox on the first day of autumn.
Science / Tides and Currents / Equinoxes: The two points in the celestial sphere where the celestial equator intersects the ecliptic; also, the times when the Sun crosses the equator at these points. The vernal equinox is the point where the MORE
Science / Astrology / Precession Of The Equinoxes: The gradual westward shift (about 50' each year) of the equinoctial points along the ecliptic due to the ecliptic due to the rotational movement of the poles of Earth's axis. This phenomena creates an MORE