Autumn Equinox 2022. The autumnal equinox marks the beginning of the astronomical autumn. The equinox occurs twice each year. Equinox occurs when day and night are equal everywhere on Earth, because the Sun, in its apparent movement in the sky, is exactly on the celestial equator.
The first Equinox occurs when the Sun crosses the celestial equator from the southern to the northern hemisphere around 21 March, representing the spring equinox in the northern hemisphere and the autumn equinox in the southern hemisphere.
When will the autumnal equinox occur in 2022?
The autumnal equinox does not occur on the same date every year, but the usual timeframe is rather narrow. Since the introduction of the Gregorian calendar in 1582, the start of astronomical autumn has occurred on 21, 22, 23 or 24 September, but most frequently on 22 or 23 September.
This year, in 2022, the autumnal equinox will occur on 23 September. After this evening, autumn will make its presence felt. The night will become longer and the day shorter until the winter solstice on 22 December 2022.
According to the Admiral Vasile Urseanu Astronomical Observatory, the autumnal equinox means that the astronomical longitude of the Sun reaches 180°. The Sun will rise and set at the same cardinal points east and west, making the length of the day equal to that of the night, regardless of latitude.
There are also exceptions in the polar regions: in the North Pole, the equinox marks the beginning of the half-year long polar night and in the South Pole the Sun rises above the horizon and stays for 6 months until the time of the spring equinox.