First Point of Libra
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The First Point of Libra, also called the autumnal equinox point, is one of the two points on the celestial sphere where the celestial equator intersects the ecliptic. It is defined as the position of the Sun on the celestial sphere at the time of the autumnal equinox. It was named after the constellation in which it occurred in ancient times - Libra. However due to precession, the point gradually moves around the ecliptic. It is currently in the constellation Virgo. The other such point, at the vernal equinox, is the First Point of Aries.
In the equatorial coordinate system the First Point of Libra is defined to have a right ascension of 12h. The declination is zero due to the position on the celestial equator.de:Herbstpunkt nl:Herfstpunt ja:秋分点