Astronomical Autumn 2025 begins today!

At 2:19 P.M. EDT today, the Sun crosses the celestial equator, marking the autumnal equinox. For a brief moment, day and night share equal length as the Northern Hemisphere bids farewell to summer and welcomes the start of astronomical autumn. Meanwhile, in the Southern Hemisphere, winter ends and spring awakens.

The equinox is a reminder of Earth’s balance in motion, a precise alignment where neither hemisphere leans toward or away from the Sun.

Autumn’s Showcase: The Double Cluster in Perseus

Few seasonal objects capture the spirit of fall observing like the Double Cluster: open clusters NGC 869 and NGC 884.

• Located about 4.5° WNW of Eta (η) Persei, the pair hovers roughly 40° high in the northeast around 10 P.M. local time.

• Both glow around 4th magnitude, each spanning half a degree, large enough to fill binoculars or a finder scope with glittering starlight.

• NGC 869 (west) is the denser of the two, while NGC 884 (east) holds the variable RS Persei, a red supergiant ranging from 8th to 10th magnitude.

Spend some time sweeping across them at low power, then zoom in to appreciate their subtle differences. It’s a true two-for-one cosmic treasure.

☀️🌙 Sun & Moon (from 40° N, 90° W)

• Sunrise: 6:46 A.M.

• Sunset: 6:56 P.M.

• Moonrise: 7:35 A.M.

• Moonset: 7:12 P.M.

• Phase: Waxing Crescent (1%)