The so-called autumnal equinox is the equal division of autumn, that is, half of the fall, and, on this day (and the equinox) the day and night are equal in length, and the further the longer the darkness until the winter solstice reaches the longest!

From a geographic point of view, in the fall equinox (and the equinox) this day, the sun directly on the equator, the north and south poles at the same time by the sun, after this day the sun began to move from the equator to the southern hemisphere, the southern hemisphere into the summer half of the northern hemisphere into the winter half of the southern hemisphere, the South Pole will gradually be irradiated by the sun until the polar day, the North Pole is gradually entering the polar night.

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