For astronomers, the day that the sun’s path and the Earth’s celestial equator intersect signifies the Autumnal Equinox. During the Equinox, the entire planet receives about 12 hours of sunlight and darkness over the 24 hour period. The name is derived from the Latin words ‘aequi’ (equal), and ‘nox’ (night).
The Autumn, or Fall Equinox occurs between September 21 and 24 in the Northern Hemisphere. The date varies slightly each year due to factors such as the precession of the Equinoxes, the Earth’s axial precession, and the cycle of leap years in the Gregorian Calendar. In the Southern Hemisphere, the Spring Equinox occurs around the same date, marking the beginning of Spring.
The start of the Fall season is when the Neopagan Sabbat of Mabon is celebrated. Also, Autumnal Equinox Day is an official national holiday in Japan, and is spent visiting family graves, and holding family reunions. Some civilizations also celebrate the Harvest Moon, which is the full moon closest to the Autumn Equinox.
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