Autumnal equinox 23 Sep 2023

Autumnal equinox

Autumn has officially begun! In the Northern Hemisphere, the autumnal equinox falls on September 23 this year, marking the beginning of autumn and the Earth and Sun"s unique positions. Today is one of the two moments in the year when day and night are equal in length, thanks to the Sun"s location exactly above the Equator. The same celestial phenomenon applies to the Southern Hemisphere, but it is their vernal equinox as they head into spring.

© Stephen Matera/Tandem Stills + Motion

palette

Today in History

In a world of their own
23 Sep 2024Sea otter
23 Sep 2025Keel-billed toucan, Costa Rica

More Desktop Wallpapers:

Tree-mendous
29 Oct 2025Ancient til trees in Fanal Forest, Madeira, Portugal
What are these unique creatures?
28 Jan 2026Whanganui National Park, Retaruke, New Zealand
What are these predators doing?
27 Sep 2023Via Krupp, Capri, Italy
2 May 2026Tŵr Mawr Lighthouse, Anglesey, Wales
Celebrating the tropics
21 Dec 2024Burning the Clocks
25 Oct 2023Grand Staircase-Escalante National Monument, Utah, USA
30 Apr 2024Cheetah in Ngorongoro Conservation Area, Tanzania
14 Apr 2026Common clownfish, Raja Ampat Islands, Indonesia
Aug 26, 2023Museum Night in Berlin
6 Mar 2026The Wave, Vejle, Denmark
20 Oct 2025International Sloth Day
17 Jun 2026Tremola Road on the Saint Gotthard Pass in Airolo, Switzerland
Aug 27, 2023Jeju Island, South Korea
Aug 25, 2023National Park Service anniversary
15 Nov 2023Rapa Valley in Sarek National Park, Sweden
14 Jul 2026Shark Awareness Day
10 Jul 2025Independence Day of the Bahamas
21 May 2026International Tea Day
6 May 2025An ultralight aircraft flying over the sands of Namibia
Jewel of the Adriatic
13 Jun 2025Vila Franca Islet, São Miguel Island, Azores, Portugal
20 Feb 2024Kinder Scout, England
21 Nov 2025World Hello Day
A stunning chamber for beautiful art
Lighting the world
28 Nov 2024City Hall, London, England