Autumn Equinox 2024 Name. While the specific date of the. Autumn equinox 2024 (beginning of astronomical autumn) on the day of the autumn (september) equinox, the sun, moving along the ecliptic, crosses the celestial equator,.

In 2024, the autumnal (fall) equinox arrives on sunday, september 22, marking the official first day of fall. This sunday, the autumnal equinox is upon us, and with it, a shift to shorter days, longer nights and the astronomical start of fall in the northern hemisphere.