September equinox

Day and night are nearly equal again, and spring begins in the south.

Next one: 23 September 2027 at 06:01 UTC, in 328 days
Day and night: About 12 hours each, all over the world
North of the equator: Autumn begins
South of the equator: Spring begins
The Sun: Rises due east, sets due west, and is right overhead at noon on the equator

Did you know?

At the North Pole, the Sun sets at the September equinox and does not rise again for about six months.
Every planet that is tilted has equinoxes. On Saturn they come about every 15 years.
It falls between 21 and 24 September, and around it you can see the Sun set almost exactly due west.

More NASA photos of September equinoxStraight from NASA’s image library, in the app

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All of night sky

Orion The Hunter, with three bright stars in a row for his belt. Ursa Major The Great Bear, home of the Big Dipper. Ursa Minor The Little Bear, with Polaris at the tip of its tail. Cassiopeia A bright W of five stars, named after a boastful queen. Scorpius The Scorpion, with red Antares at its heart. Leo The Lion, whose head is a backwards question mark of stars.

Facts: Times worked out with Jean Meeus’s method (Astronomical Algorithms) and checked against the US Naval Observatory. Photo: NASA/JPL/Space Science Institute. Open September equinox in the app.