The fall equinox occurs on Tuesday, September 22, 2026, at 8:05 p.m. Eastern time, marking the beginning of fall in the Northern Hemisphere and spring in the Southern Hemisphere. During the equinox, day and night are nearly equal in length. The sun will be directly overhead at noon at the equator, and both the north and south poles will receive sunlight simultaneously.
Equinoxes have been celebrated globally for centuries. In Japan, public holidays are observed during this time, while at the Mayan site of Chichen Itza in Mexico, people gather to witness a shadow pattern resembling a serpent descending the pyramid known as El Castillo.
The Earth's orbit around the sun is tilted, causing unequal distribution of sunlight throughout the year. On the equinox, the Earth's tilt is neutral, allowing for equal sunlight in both hemispheres. The sun rises almost directly in the east and sets almost directly in the west.
The term equinox derives from Latin words meaning 'equal' and 'night', reflecting the near-equal duration of day and night. The Northern Hemisphere's fall equinox can occur between September 21 and 24, while the spring equinox occurs between March 19 and 21.
Solstices represent the extremes of the Earth's tilt toward or away from the sun, resulting in the longest and shortest days of the year. The summer solstice occurs between June 20 and 22, while the winter solstice occurs between December 20 and 23.
Meteorological seasons differ from astronomical seasons, as they are based on temperature cycles. Meteorologists define spring as starting on March 1, summer on June 1, fall on September 1, and winter on December 1.