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September equinox - It is officially (astronomical) autumn!

07:00
22 September 2025

September equinox
It is officially (astronomical) autumn!

Stonehenge at sunsetStonehenge is a popular destination each year for people to mark the equinox. - © shutterstock / Chuta Kooanantkul

The 2025 September Equinox takes place today, officially beginning astronomical autumn and ending the summer season.

The September Equinox indicates the point in time where the Sun will be directly above Earth’s equator, providing an equal amount of daylight and nighttime. This occurred at 01:43 pm this afternoon.

The word equinox itself is Latin and means “time of equal day and night.”

The equinox marks the beginning of astronomical autumn, meteorological autumn began earlier this month on the first.

Astronomical autumn lasts until the winter solstice, this year on December 21, although meteorological winter begins December 1.

From this point on, in the Northern Hemisphere, the daylight hours start to shrink until the Winter Solstice, thanks to the Earth’s North Pole tilting away from the Sun.

Astronomical vs meteorological autumnread more
Ryan Hathaway
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