The equinox, which occurs twice a year, is when the sun crosses the celestial equator, making day and night of equal length all over the world.
The next equinox will occur on September 22, 2025, and will be the autumnal equinox in the Northern Hemisphere and the vernal equinox in the Southern Hemisphere. The equinox is a significant astronomical event that has been celebrated by cultures around the world for centuries.