Autumn equinox 2027

315 nights to go

Wednesday 22 September 2027 · In the daytime

The Moon that night: 53% lit. If the sky is clear.

The autumn equinox comes just after midnight Mountain Time on 23 September 2027 (late on 22 September in Pacific time). Day and night are close to equal, and from now until March the nights in the Northern Hemisphere are longer than the days: more time for stars.

In September, day and night are about the same length again. After that, the nights get longer. Fall is here.

At the autumn equinox the Sun crosses the equator heading south in our sky. Day and night are nearly equal everywhere, then the northern nights grow longer until the December solstice.

Astronomy-engine puts the September 2027 equinox at 12:01 am Mountain Time on 23 September, which is 11:01 pm on 22 September in Pacific time, so the date depends on your zone. Longer nights mean earlier dark: by late September, stars are out before 8 pm in much of the country.

Earth seen from space, half in sunlight, with the Americas visible. — Earth on the December solstice of 2011, from the GOES-13 weather satellite, with the north half leaning away from the Sun. Photo: NASA/NOAA GOES Project (NASA Image and Video Library, public domain).

Where to look

Watch the sunset: on the equinox the Sun sets almost due west again.

What to do

Add a fourth mark for the sunset on your window: it's back near the March one.
Notice how much earlier it gets dark than in June.
Use the longer nights: look for the Summer Triangle overhead after dark.

More sky events

“If it's cloudy, don't worry. The planets will still be there tomorrow night.”