Equinox Sky Alert: Northern Lights, Planet Parade & More Dazzle Sept 22–23, 2025
Monday, September 22 marks the autumnal equinox, the moment the Sun crosses Earth’s equator. Day and night are nearly equal in length across the globe during an equinox earthsky.org. In 2025 this happens at 18:19 UTC on Sept 22 earthsky.org earthsky.org. For the Northern Hemisphere, it’s the first day of autumn; for the Southern Hemisphere, spring begins earthsky.org. Equinoxes are more than just a date on the calendar – they also have an interesting side effect for skywatchers: an “equinox effect” that can amplify the Northern Lights!
