Equinox

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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 ?
Since it is only possible to view the auroras simultaneously in both poles during the Vernal and Autumnal equinox days, NHK has opted to push off the broadcast to September.