|Dates and Times of the Seasons Calculator|
For Gregorian Years 1600 to 2200
Solar coordinates based on the Full-Precision VSOP87 Theory, Series C IAU 2000B Nutation Series
Definitions of the Solstices and Equinoxes Used Here
The dates and times of the Northern/Southern solstices and equinoxes are computed according to the following definitions:
The solstices refer to that point in the sky where the sun appears to reach its highest or lowest midday elevation in the sky and where it appears to hover for a day or so before slowing starting to move back in the opposite direction, southward or northward, depending on the season, a little more each day. There are two solstices each year which mark the dates on which the summer and winter seasons begin.
The equinoxes refer to those dates of the year where the days and nights throughout the world are most closely equal in length (closer to 12h/12h) than on any other date of the year. There are two equinoxes each year marking the dates on which the spring and autumn seasons begin and the apparent geocentric sun crosses the celestial equator.
Let: Blue Seasons = Northern hemisphere and Red Seasons = Southern hemisphere
USNO-Ref: (Tries to open in a new tab)
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