Happy Autumnal Equinox 2025!

Today, Monday, September 22nd, 2025 is the first official day of autumn for the northern hemisphere. The word autumn simply indicates the season following summer. The origin of the word is not known, but this day marks the moment when the Earth's orbit causes the Sun to cross Earth's equator, and the southern hemisphere's spring season begins, and the northern hemisphere's autumnal season commences. This year the Autumnal Equinox occurs at 11:19amPST.

On the autumnal equinox, the ever moving boundary between light and dark on Earth cuts right through both the north and south poles. As we move into autumn, the north pole will experience longer and longer nights as the December solstice approaches.

The Earth is also moving closer to the sun. the next perihelion occurs on January 3rd, 2026 the day of the year that our planet is closest to the Sun. The southern hemisphere summers are more intense due to closer proximity to the sun, and therefore the northern hemisphere winters are less harsh than they could be. So today summer ends, but at least we are getting closer to the sun!

Image sources:

• https://www.zmescience.com/science/what-causes-the-seasons-042331/

• https://www.space.com/vernal-equinox-2020-earliest-spring-124-years.html