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Ephemeris: 10/23/2025 – Finding Perseus the hero

October 23, 2025 Comments off

This is Ephemeris for Thursday, October 23rd. Today the Sun will be up for 10 hours and 35 minutes, setting at 6:44, and it will rise tomorrow at 8:10. The Moon, 2 days past new, will set at 7:21 this evening.

About a third the way from the east northeastern horizon to the zenith at 9 p.m. and below the letter W shaped constellation of Cassiopeia the queen is Perseus the hero. It’s kind of an odd shape for a hero, To me it looks kinda like the cartoon roadrunner. To those who’re mathematically inclined its shape is also like the Greek letter pi on its side. It’s two brightest stars are Mirfak and Algol the demon star, the still winking eye of Medusa. Look at the area around Mirfak with binoculars and a large group of stars just below naked eye visibility will appear. It’s called the Alpha Persei Association. That’s because Mirfak is also known as Alpha Persei. The group is about 560 light years away, which are farther away than the Pleiades, which is below and to the right of them.

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

Finding Perseus the hero, slayer of Medusa, rescuer of Andromeda. Seen in three frames: first, the star field; second, the constellation lines of Perseus and nearby prominent constellations; third the figure of Perseus, holding the severed head of Medusa. Created using Stellarium, LibreOffice Draw for labels, and GIMP.
Alpha Persei Association
The Alpha Persei Association. The brightest star is Mirfak (Alpha Persei). This a a crop from a photograph taken February 18, 2017, Canon EOS Rebel T5, 121 seconds, f/3.5, 18mm fl., ISO 3200. Credit Bob Moler.
Categories: Constellations, Ephemeris Program, Mythology, Observing