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Ephemeris: 11/04/2025 – The Persephone Period starts tomorrow
This is Bob Moler with Ephemeris for Election Day for some, Tuesday, November 4th. Today the Sun will be up for 10 hours and 1 minute, setting at 5:26, and it will rise tomorrow at 7:26. The Moon, 1 day before full, will set at 7:41 tomorrow morning.
Tomorrow the daylight hours drops below 10 hours. This begins something which has been called the Persephone Period. It is named after the Greek goddess Persephone, goddess of spring, who is abducted by Hades the god of the underworld to be his bride. When he did, all the vegetation on the earth began to die. So he had to allow her to appear above ground for a part of the year so that the vegetation and the grain would grow. So the Persephone Period is the time when she is in the underworld. It lasts from now to early February. That may have worked for a country like Greece around the Mediterranean, but we have harsher weather here. It takes a much longer time for spring to arrive.
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
Ephemeris: 10/23/2025 – Finding Perseus the hero
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
Ephemeris: 10/21/2025 – Finding Andromeda
This is Ephemeris for Tuesday, October 21st. Today the Sun will be up for 10 hours and 41 minutes, setting at 6:47, and it will rise tomorrow at 8:07. The Moon is new today, and won’t be visible.
Tonight at 9:00 PM Saturn is in the southeast, with the Great Square of Pegasus above and to the left. Off the leftmost star of the Great Square, called Alpheratz, are two curved lines of stars to the left and a bit below, and slightly diverging. They might be mistaken for the hind legs of the horse, which is flying upside down. It’s another constellation, that of Andromeda the Princess, daughter of Cassiopeia, the W shaped constellation to the upper left. Andromeda was rescued by hero Perseus which is another constellation left of her, which we’ll get to later on this week. Andromeda’s claim to scientific fame is the large galaxy located there, the Great Andromeda Galaxy, probably the farthest thing one can spot with the naked eye.
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
Andromeda is part of the Great Star Story of Autumn. My take on it is linked Here.
Ephemeris: 10/16/2025 – The Anishinaabe saw a Moose where Pegasus is
This is Ephemeris for Thursday, October 16th. Today the Sun will be up for 10 hours and 55 minutes, setting at 6:55, and it will rise tomorrow at 8:01. The Moon, 3 days past last quarter, will rise at 3:57 tomorrow morning.
High in the southeast at 10 PM is the constellation officially called Pegasus the flying horse. The front part of his body is a pattern of stars we call the Great Square of Pegasus, and he’s flying upside down, quite an aerobatic horse. His wings are not seen in the stars, however his neck and head, up to his nose is, along with his front legs. The Anishinaabe peoples of this area call it Mooz, from which we get our word moose. He’s right side up, facing the west. His head is where we see the front legs of Pegasus, and his antlers are above it where there is another official constellation made of faint stars called Lacerta, which is a lizard. Not everyone sees the same figure in the stars.
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
Ephemeris: 09/26/2025 – Pegasus rising
This is Ephemeris for Friday, September 26th. Today the Sun will be up for 11 hours and 56 minutes, setting at 7:32, and it will rise tomorrow at 7:36. The Moon, 3 days before first quarter, will set at 9:19 this evening.
Saturn is well up in the east southeastern sky at 10 PM. This is the brightest “star” in that direction. Below it, at about the 4 o’clock position from it is Fomalhaut, which I sometimes call the loneliest star in the sky, because without Saturn or another planet in that direction it seems pretty much alone low in the south. Above and a bit to the left of Saturn is the Great Square of Pegasus A four star group standing on one corner which is the body of Pegasus the flying horse. Between Saturn and the Great Square is a faint and small circle of five or six stars called the Circlet, an asterism, which is a loop around one of the fish of Pisces the fish. Pisces is two fish held together by a long rope.
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
Ephemeris: 09/15/2025 – Last month to view the southern Milky Way from Michigan
This is Bob Moler with Ephemeris for Monday, September 15th. Today the Sun will be up for 12 hours and 30 minutes, setting at 7:52, and it will rise tomorrow at 7:23. The Moon, 1 day past last quarter, will rise at 1:14 tomorrow morning.
September is the second of the two months we get to see the southern part of the Milky Way in the evening sky. At 10 PM the asterism of the Teapot of the constellation Sagittarius is pouring its tea on the southwestern horizon. It is in that direction that we look to the center of the Milky Way. Unfortunately there are clouds of dust and gas between us and the center, so we cannot see it visually, though it can be seen by radio waves and other means. There are a host of objects visible in binoculars and small telescopes. One does not need a star map to be able to find them, just point a telescope at low power or binoculars in that direction and sweep around slowly. There are treasures of star clusters and nebulae to be found.
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
In the image above the amount of detail of the stars is approximately that of a pair of binoculars. The various nebulae and star clusters are denoted with M numbers. These are some of the brightest, what we call deep sky objects, in the catalog by Charles Messier, who is looking for comets. He numbered them as he came across them. The brightest star cluster is M7, which Claudius Ptolemy recorded in the 2nd century CE. The brightest nebula is M8, the Lagoon Nebula out of which a star cluster is being formed. In binoculars, it looks like a short horizontal gash. Next in brightness is M17, a fuzzy spot in binoculars, but appears as a glowing check mark, or swimming swan in a telescope. M20, the Trifid Nebula, is the next brightest nebula in which dark dust lanes divide it into three lobes. M16, the Eagle Nebula is very dim. Most of the time I miss the nebulosity, but its embedded star cluster is quite easily seen. The rest of the Messier objects are star clusters or a star cloud. Of these M22 is a globular star cluster and one of the easiest of these clusters to resolve, though it might take a telescope of 150 mm (6″) diameter to do it.
Ephemeris: 09/12/2025 – Cassiopeia through the year
This is Ephemeris for Friday, September 12th. Today the Sun will be up for 12 hours and 39 minutes, setting at 7:58, and it will rise tomorrow at 7:19. The Moon, 2 days before last quarter, will rise at 10:19 this evening.
The constellation of Cassiopeia the queen looks to most of us like the letter W. However, since it is circumpolar, that is it seems to move around the North Pole of the sky without setting. It represents to us with various orientations. When it’s seen now in the evening in the northeast, it kind of looks like a misshapen number 3. In early winter it would be nearly overhead and be the letter M, not the University of Michigan block letter M, but the angular University of Minnesota M. In early spring, it’s in the northwestern sky as the Greek capital letter sigma. And finally in early summer it’ll be low in the north and become the upright letter W. I’ll return to Cassiopeia and tell her story later this autumn.
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.
Ephemeris: 09/11/2025 – Finding Pegasus the flying horse
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
Ephemeris: 08/25/2025 – Two fascinating constellations in and near the Summer Triangle
This is Bob Moler with Ephemeris for Monday, August 25th. Today the Sun will be up for 13 hours and 33 minutes, setting at 8:31, and it will rise tomorrow at 6:58. The Moon, 2 days past new, will set at 9:27 this evening.
There are two small constellations in and near the Summer Triangle of bright stars. Both are near Altair the bottom star of the triangle in the southeast. The first is Delphinus the dolphin to the left of Altair. Delphinus is made-up of a small squished box of stars with another star below. It does look a dolphin leaping out of the water. The legendary Greek poet Arion, according to myth, was rescued by a dolphin. Also, the little squished box is an asterism called Job’s Coffin, though no one knows the origin of that name. The second constellation is above Altair, and within the Summer Triangle. It is called Sagitta the arrow. The stars do line up to look like a short arrow. It’s supposed to represent Cupid’s dart.
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
Ephemeris: 08/18/2025 – Wandering through Sagittarius with binoculars
This is Ephemeris for Monday, August 18th. Today the Sun will be up for 13 hours and 54 minutes, setting at 8:43, and it will rise tomorrow at 6:50. The Moon, 2 days past last quarter, will rise at 2:12 tomorrow morning.
Let’s look around the Teapot shape of stars that is the constellation of Sagittarius. A pair of binoculars or a telescope with a very low magnifying power is all that’s needed. The purpose here is not so much to make things bigger, but make them brighter. Right off the tip of the teapot’s spout is a large and bright patch of light. This is the farthest we can see, in visible light that is, toward the center of our galaxy, part of the central bulge. Astronomer Walter Baade discovered that fact in the mid 1940s. The center of the galaxy is 4 moon-widths or 2 degrees to the right of it, but obscured by a cloud of interstellar dust. It is called the Large Sagittarius Star Cloud or Baade’s Window, peering out 25 thousand light years away.
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
Bob Moler's Ephemeris Blog 