The equinox, which happens twice a 12 months, is when the solar crosses the celestial equator, making day and night time of equal size everywhere in the world.
The following equinox will happen on September 22, 2025, and would be the autumnal equinox within the Northern Hemisphere and the vernal equinox within the Southern Hemisphere. The equinox is a major astronomical occasion that has been celebrated by cultures around the globe for hundreds of years.