Autumn equinox  Sep 22, 2025

Fall isn"t just marked by the calendar. Each September, Earth"s subtle tilt brings the autumn equinox—one of two times a year when day and night are nearly equal in length. It marks the beginning of fall in the Northern Hemisphere. From solar alignments to changing leaves, nature offers its own quiet signals that the season has shifted. While for most of us it may seem like just another day, ancient cultures paid close attention to this change. Sites like Chichén Itzá in Mexico and England"s Stonehenge were designed to align with the rising or setting sun during equinox days.

© Danita Delimont/Getty Images

fShare Share pSave tPost