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Ephemeris: 12/08/2025 – Hyades, half sisters of the Pleiades
This is Ephemeris for Monday, December 8th. Today the Sun will be up for 8 hours and 54 minutes, setting at 5:02, and it will rise tomorrow at 8:08. The Moon, 3 days before last quarter, will rise at 9:19 this evening.
At 8 o’clock this evening the constellation of Orion the hunter is still in the act of rising with one leg still stuck in the snow. What is above him is the constellation of Taurus the bull. His face is a letter V of stars or as a letter A, is the star cluster called the Hyades. In Greek myth the stars are the half sisters of the Pleiades, which are right above them. The Hyades star cluster is very special. They don’t look as splashy as the Pleiades which are younger and still have their hot blue white stars. However, the Hyades are much closer, a third as far as the Pleiades. In fact they’re close enough to be measured by trigonometry using Earth’s orbit as the base of a triangle, before satellites. Which was critical in measuring distances beyond the solar system.
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: 11/21/2025 – Finding Taurus the bull
This is Ephemeris for Friday, November 21st. Today the Sun will be up for 9 hours and 21 minutes, setting at 5:09, and it will rise tomorrow at 7:49. The Moon, 1 day past new, will set at 5:36 this evening.
Low in the east at 8 this evening and below the beautiful Pleiades star cluster is Taurus the bull. His face is a letter V shape of stars lying on its side, the star cluster Hyades, which in Greek Mythology were the half-sisters of the Pleiades, with the bright orange-red star Aldebaran at one tip of the V as its angry bloodshot eye. Aldebaran is actually about halfway between us and the cluster. The Pleiades star cluster is in his shoulder. Taurus is seen charging downward at that hour, the rising constellation of Orion. Taurus in Greek mythology was the form the god Zeus assumed when he carried off the maiden Europa. Europa’s still with him as a moon orbiting Zeus’ Roman counterpart, the planet Jupiter.
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: 10/24/2025 – How to spot the Double Cluster
This is Ephemeris for Friday, October 24th. Today the Sun will be up for 10 hours and 32 minutes, setting at 6:42, and it will rise tomorrow at 8:11. The Moon, 3 days past new, will set at 7:55 this evening.
This pair of objects are about as dim as one can see with the naked eye, but very rewarding for binoculars or small telescope, the Double Cluster. It’s a fine pair of star clusters just below the W of the constellation of Cassiopeia the queen located in the northeast. Draw a vertical line down from the middle star of the W through the next star into the glow of the Milky Way. The Double Cluster appears to the unaided eye as a brighter glow of the Milky Way. This is confirmed with binoculars. But in a small telescope it becomes two clusters of sparkling diamonds. The clusters are much younger than the Sun, so their brightest stars are blue-white to our eyes. The average distance of the two from Earth is 7,500 light years.
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: 07/14/2025 – The celestial scorpion crawls along the southern horizon
This is Ephemeris for Monday, July 14th. Today the Sun will be up for 15 hours and 15 minutes, setting at 9:26, and it will rise tomorrow at 6:11. The Moon, 3 days before last quarter, will rise at 11:42 this evening.
There’s a large constellation located low in the south at about 11 tonight. It’s Scorpius the scorpion. Its brightest star is Antares in its heart, a red giant star, that I’ve gotten calls about it as being a UFO. From Antares to the right is a star, then a vertical arc of three stars, that is its head. The Scorpion’s tail is a line of stars running down to the left of Antares, swooping to the horizon before coming back up and ending in a pair of stars that portray his poisonous stinger. There is a beautiful star cluster, seen in binoculars at that first bend in the tail that is unfortunately too low, at three degrees altitude, to appreciate from this far north. I was very impressed with it when spotting it in binoculars from the Florida Keys when I was down there in 1986 to observe Halley’s Comet. It has several names, including the Northern Jewel Box Cluster.
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.
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: 10/28/2024 – The Pleiades or Seven Sisters and their half sisters
This is Ephemeris for Monday, October 28th. Today the Sun will be up for 10 hours and 20 minutes, setting at 6:36, and it will rise tomorrow at 8:17. The Moon, halfway from last quarter to new, will rise at 5:22 tomorrow morning.
The beautiful star cluster of the Pleiades is seen low in the east northeastern sky after 9:00 PM. It is also known as the Seven Sisters. It has been known as a group of female stars in many cultures. Also, the Ancient Greeks, because they thought that the Pleiades shape looked something like a sail, Also, Pleiades is very close to the Greek name for sail, and that its appearance in the morning sky in early summer heralded the beginning of the summer sailing season on the Mediterranean Sea. According to Greek mythology the Pleiades have half sisters, also seven in number, with the same father, Atlas, but a different mother, called the Hyades which rises about an hour later, and fills out the face of Taurus the bull.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 09/23/2024 – Scanning the Milky Way with binoculars
This is Ephemeris for Monday, September 23rd. Today the Sun will be up for 12 hours and 5 minutes, setting at 7:37, and it will rise tomorrow at 7:33. The Moon, 1 day before last quarter, will rise at 10:50 this evening.
Now that the Moon has fled the early evening skies the Milky Way is showing up again, if you’re at a dark site. I’ve always said that August and September are the best times to view what I call the summer Milky Way, even now that it’s not technically summer anymore. The Teapot asterism in the constellation of Sagittarius is low in the south-southeast, pouring its tea on the horizon. It is in that direction we are looking towards the center of our Milky Way Galaxy. The Summer Triangle is high in the South with Vega and Deneb, two of its stars near the zenith. All the Milky Way is an invitation to scan it with the pair of binoculars or a very low power telescope. One doesn’t need a chart. Just wander through the Milky Way to find many star clusters, groups of stars and nebulae.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum (Some binocular wonders)
The Coathanger
The North American Nebula
Ephemeris Extra: Taurus and its two bright star clusters
Based on an article published in the November 2023 issue of the Stellar Sentinel the newsletter of the Grand Traverse Astronomical Society.
In my October presentation to the society I talked about the stars of autumn, moving generally from the constellations close to summer and ending pretty much against the constellations of winter ending with the constellation of Taurus and with the wonderful Pleiades or Seven Sisters. In this article I’ll take a little bit closer look at the Pleiades and especially the Hyades, the face of Taurus the bull.
On the previous page is a family portrait of the Pleiades and Hyades. Yes, family portrait. In Greek mythology, the Hyades are the half sisters of the Pleiades. The god Atlas is their father, Pleione seems to be the mother of the Pleiades, and Aethra is the mother of the Hyades. In astronomical terms the Hyades would then be the older sisters of the Pleiades.
The Hyades is a star cluster that is 153 light years away. It is the closest star cluster to us and somewhat over 6 times the age of the Pleiades. The younger and splashier Pleiades are around 444 light years away, and only 100 million years old. Whereas the Hyades are over 600 million years old. The Pleiades still contain hot blue-white stars which have died out by the time of the age of the Hyades. The brightest star of the letter V of stars is Aldebaran, Taurus’ angry bloodshot eye. It doesn’t belong to the Hyades, being about half the distance.
While the Hyades is not as splashy as the Pleiades are and has less of a role in mythology. However, it did play an important part in history when Taurus was the first constellation of the Zodiac some 4,000 years ago, due to precession of the equinoxes. This is because the letter A, the first letter of our alphabet is taken from the stars of the face of Taurus the bull in what looks to us like a V. But it was turned around to be the A we have today. Back then it was called Aleph the first letter of the alphabet for middle eastern cultures.
The Hyades is also important in astronomical history in that it helps us measure distances to more distant star clusters. The Hyades was the only star cluster close enough to measure its distance by the parallax method before the advent of the European Space Agency’s Hipparcos and Gaia satellites. If one matches stars on the Hertzsprung-Russell diagram of intrinsic brightness versus surface temperature with other star clusters the stars of the main sequence, where stars spend most of their lives burning hydrogen. The difference in the brightness of the main sequence stars gives the measure of how other star clusters measure up as far as distance since the main sequence is a relatively narrow distribution of stars. This works only with star clusters because there are many stars at the same distance which happen to be about the same age. And enough stars to establish the main sequence since stars at later stages of life may have the same temperature, but vastly different brightnesses.
The Pleiades are so large that most telescopes will not allow one to see all the brighter stars at once, so binoculars are the best way to view them. At a dunes star party a few years ago, before COVID, I used my 11-inch (279 mm) Newtonian telescope, which has a 55 inch (1,397 mm) focal length, with a 40 millimeter eyepiece to view the Pleiades. A 40 millimeter eyepiece in that scope gives too low a magnification to use the entire diameter of the primary mirror. All the light doesn’t make it into the eye. That eyepiece gave me about 35 times magnification, so the main stars of the cluster fit into the field of view. The photograph above is nice and all that, but looking with the eye visually at the Pleiades, even with binoculars, you’ll notice something quite different from the photographs. In photographs to make a star brighter you make it bigger. But the eye has a much greater dynamic range. The stars are incredibly brilliant blue white-points of light in the case of the Pleiades. Absolutely beautiful, much more beautiful than any photograph. Not to disparage photographs, but photographs can do what the eye cannot. That is, store light to bring out very faint objects and details. So, let’s take a final look at the Pleiades in a photograph by GTAS member Dan Dall’Olmo.
Ephemeris: 11/06/2023 – The Pleiades or Seven Sisters
This is Ephemeris for Monday, November 6th. Today the Sun will be up for 9 hours and 57 minutes, setting at 5:25, and it will rise tomorrow at 7:28. The Moon, 1 day past last quarter, will rise at 1:18 tomorrow morning.
A marvelous member of the autumn skies can be found low in the east after 8 in the evening. It is the famous star cluster called the Pleiades or the Seven Sisters. I might also add the ‘Tiny Dipper’. Many people can spot a tiny dipper shape in its six or seven stars, and mistake it for the Little Dipper. With binoculars, one can see over a hundred stars appear, along with the dipper shape of the brightest. In photographs, the Pleiades actually contain wisps of the dust they are currently passing through. In Greek mythology, the sisters were daughters of the god Atlas and Pleione.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT –5 hours). They may be different for your location.
Addendum
I’ll be coming back to the Pleiades from time to time over the autumn and winter months to cover, especially, the mythology of the Pleiades from different cultures.
11/21/2022 – Ephemeris – The Pleiades or the Seven Sisters
This is Ephemeris for Monday, November 21st. Today the Sun will be up for 9 hours and 21 minutes, setting at 5:09, and it will rise tomorrow at 7:49. The Moon, 2 days before new, will rise at 6:10 tomorrow morning.
A marvelous member of the autumn skies can be found low in the east after 8 in the evening. It is the famous star cluster called the Pleiades or the Seven Sisters. I might also add the ‘Tiny Dipper’. Many people can spot a tiny dipper shape in its six or seven stars, and mistake it for the Little Dipper. With binoculars, one can see over a hundred stars appear, along with the dipper shape of the brightest. In photographs, the Pleiades actually contain wisps of the dust they are currently passing through. In Greek mythology, the sisters were daughters of the god Atlas. I’ll be revisiting the Pleiades several times this autumn, winter, and before they disappear in the west in evening twilight next spring.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
Pleiades finder animation for 8:30 pm tonight, November 21, 2022. Mars is the interloper this year, seen between the horns of Taurus the Bull. The V of stars that make up the face of Taurus the bull is a star cluster of stars called the Hyades. In Greek mythology, they are the half-sisters of the Pleiades. Created using Stellarium, LibreOffice Draw, and GIMP.
The Pleiades, about what you’d see in binoculars. To the naked eye, six or seven stars might be glimpsed. As star clusters go, it might seem small and unremarkable, but the Pleiades is nearby, and the brightest star cluster visible. Its stars are regarded by cultures around the world as female stars, generally sisters. Credit: Mine.
Bob Moler's Ephemeris Blog 