Equinox

(redirected from First Point of Aries)
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Related to First Point of Aries: right ascension, sidereal time

EQUINOX. The name given to two periods of the year when the days and nights are equal; that is, when the space of time between the rising and setting of the sun is one half of a natural day. Dig. 43, 13, 1, 8. Vide Day.

References in periodicals archive ?
The First Point of Aries really was in Aries when it was named roughly 2,000 years ago.
Ecliptic coordinates (ecliptic longitude and latitude) use the ecliptic as the great circle; the zero point again is the first point of Aries.