This year, the fall equinox is scheduled for September 22, 2021 at 9:21 p.m. 3 seconds (French time), according to the Institute of Celestial Mechanics and Ephemeris Calculus. At this moment, the sun will pass exactly at the zenith of the equator. Day and night will have exactly the same length (12 hours) before the night begins to progress, a few minutes a day as the fall progresses.
