Home > Constellations, Ephemeris Program, Observing > Ephemeris: 09/11/2025 – Finding Pegasus the flying horse

Ephemeris: 09/11/2025 – Finding Pegasus the flying horse

September 11, 2025

This is Bob Moler with Ephemeris for Thursday, September 11th. Today the Sun will be up for 12 hours and 43 minutes, setting at 8:00, and it will rise tomorrow at 7:18. The Moon, 3 days before last quarter, will rise at 9:43 this evening.

While we’ve been watching the stars and constellations of summer and the Milky Way, the constellations of autumn have been sneaking up on us from the east. Low in the east at 9 PM is one of the greatest constellations of autumn, Pegasus the flying horse. Her body or at least the front part of it is a large square of stars called the Great Square of Pegasus. It is an almost perfect rectangle. However, as she’s rising, it’s standing on one corner. This year it is above and left of Saturn. From the upper star are her front legs, from the rightmost star her neck and head extend in the stars. And from the left star of the square are what might look like her hind legs but aren’t. Only half of her body is in the stars. It’s another constellation, Andromeda.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

The four stars of the Great Square of Pegasus can be seen in the east. This year they're above the planet Saturn.
As autumn approaches. the four stars the Great Square of Pegasus can be seen in the east. This year they’re above the planet Saturn. In mid autumn Pegasus will be high in the south flying upside down, apparently a very aerobatic flying horse. Her story belongs to the great star story of the autumn constellations, of which I’ve given my take on here. Created using Stellarium, LibreOffice Draw, and GIMP.
Categories: Constellations, Ephemeris Program, Observing Tags: