Autumn Equinox 2025: Longer Nights Begin | JQJO

The autumnal equinox occurs on September 22, 2025, at 2:20 p.m. EDT. This marks the beginning of astronomical autumn in the Northern Hemisphere, with longer nights and cooler temperatures. The equinox, derived from Latin for "equal night," signifies the sun's crossing of the celestial equator, resulting in roughly equal day and night lengths. Conversely, the Southern Hemisphere begins spring. The event is ideal for stargazing; the article recommends equipment for astrophotography.