Archive
Ephemeris: 12/10/2025 – Taking a look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, December 10th. Today the Sun will be up for 8 hours and 52 minutes, setting at 5:02, and it will rise tomorrow at 8:10. The Moon, 1 day before last quarter, will rise at 11:45 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Saturn is the brightest star-like object in the southern sky as soon as it gets dark. In a telescope Saturn sports a very thin ring, half a degree from being edge on and slowly opening. Normally, I’d say that Saturn’s rings are easy to see in a telescope. In a couple of months the rings will be much more visible in telescopes. Jupiter will rise at 7:29 PM in the east-northeast, beneath Castor and Pollux, the bright stars of Gemini. Jupiter’s 4 brightest moons can be seen even in binoculars, and shift position night to night. Tonight they will all be in line on one side of the planet. Mercury might be spotted very low in the east-southeast by 7 AM tomorrow morning.
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: 12/09/2025 – Aldebaran, the “Follower”
This is Ephemeris for Tuesday, December 9th. Today the Sun will be up for 8 hours and 53 minutes, setting at 5:02, and it will rise tomorrow at 8:09. The Moon, 2 days before last quarter, will rise at 10:34 this evening.
Tonight will be the night of the earliest sunset of the year. For the last few nights the Sun has been setting within the same minute. Soon the Sun will set noticeably later.
The bright star Aldebaran appears at the lower left tip of a letter V group of stars laying on it’s side, the Hyades star cluster and the face of Taurus the Bull. It’s in the east in the evening, above Orion. Aldebaran isn’t actually part of the group. The cluster is about 153 light years away, while Aldebaran is 65. The star has an orange hue because its surface is cooler than the Sun’s. However, Aldebaran is 44 times larger in diameter, and shines 425 times brighter than the Sun. The name Aldebaran means “Follower” because it follows the Pleiades star cluster across the sky.
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: 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: 12/04/2025 – Orion survives a full moon
This is Ephemeris for Thursday, December 4th. Today the Sun will be up for 8 hours and 59 minutes, setting at 5:02, and it will rise tomorrow at 8:04. The Moon, at full today, will rise at 4:24 this evening.
While the full moon overpowers most stars, the bright stars of winter persist. This is even true with tonight’s supermoon, a bit larger and brighter than average. Nowhere in the sky is there a concentration of bright stars as there is in the winter sky. I know it’s not winter yet, but if you stay up late enough, say 10 PM, all the winter stars will be in the sky. Last to rise is the brightest star of all, Sirius. And by 10 o’clock will be low in the southeast. Jupiter has joined the winter stars this year, outshining them all. As a constellation the mighty hunter Orion is easiest to spot on a full moon night, containing seven very bright stars, with three bright stars in a straight line as his belt, which most folks find as his most distinctive feature.
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: 12/03/2025 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Bob Moler with Ephemeris for Wednesday, December 3rd. Today the Sun will be up for 9 hours, setting at 5:02, and it will rise tomorrow at 8:03. The Moon, 1 day before full, will set at 7:59 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Saturn is the brightest star-like object in the southern sky as soon as it gets dark. In a telescope Saturn sports a very thin ring, 4/10ths of a degree from being edge on. The rings are slowly opening up. Normally, I’d say that Saturn’s rings are easy to see in a telescope. In a couple of months the rings will be much more visible in telescopes. Jupiter will rise at 8 PM in the east-northeast, beneath Castor and Pollux, the bright stars of Gemini. Jupiter’s 4 brightest moons can even be seen in binoculars, and shift position night to night. Mercury might be spotted low in the east-southeast by 7 AM tomorrow morning, having risen 45 minutes earlier.
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: 11/26/2025 – Checking out the naked eye planets
This is Ephemeris for Wednesday, November 26th. Today the Sun will be up for 9 hours and 11 minutes, setting at 5:05, and it will rise tomorrow at 7:55. The Moon, 2 days before first quarter, will set at 10:49 this evening.
Pausing my exploration of AI to check out the naked eye planets this week. Mars and Mercury are too close to the Sun to be seen. Saturn is the brightest star like object in the southeastern sky as soon as it gets dark. In a telescope Saturn sports a very thin ring, 4/10ths of a degree from being edge on. In 4 days the rings will slowly start to open up. Normally, I’d say that Saturn’s rings are easy to see in a telescope. Currently, the rings appear extremely thin and can be difficult to pick up. Jupiter will rise at 8:29 PM in the east-northeast. Beneath Castor and Pollux, the bright stars of Gemini. By 7 AM, it will appear high in the west southwest, above the stars Procyon below and Sirius, near the horizon. Venus will rise at 7:04 in the east southeast and will probably not be visible.
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: 11/19/2025 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, November 19th. Today the Sun will be up for 9 hours and 25 minutes, setting at 5:10, and it will rise tomorrow at 7:46. The Moon, 1 day before new, will rise at 8:28 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Saturn is the brightest star like object in the southeastern sky as soon as it gets dark. In a telescope Saturn sports a very thin ring, 4/10ths of a degree from being edge on. In 4 days the rings will slowly start to open up. Normally, I’d say that Saturn’s rings are easy to see in a telescope. Currently, the rings appear extremely thin and can be difficult to pick up. Jupiter will rise at 8:58 PM in the east-northeast. By 6:30 AM, it will appear high in the southwest, near the stars of Gemini, with Orion and the other bright stars of winter in the southwest. Venus, which will rise at 6:48 AM will be difficult to spot in the morning twilight.
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: 11/18/2025 – What other cultures see in the Pleiades
This is Ephemeris for Tuesday, November 18th. Today the Sun will be up for 9 hours and 27 minutes, setting at 5:11, and it will rise tomorrow at 7:45. The Moon, 2 days before new, will rise at 7:22 tomorrow morning.
Let’s look at how some other cultures saw the Pleiades, the star cluster that is seen in the eastern sky these evenings. To the Anishinaabe native peoples around here, the Pleiades is the “Hole in the Sky” or the seven stones that are heated for the sweat lodge ceremony. To the Kiowa, these were sisters who were whisked up into the sky from the top of Devil’s Tower in Wyoming, where they were threatened by a huge bear. An Iroquoian legend has seven daughters who danced all day and were drawn into the sky, along with a black bear who danced with them. One daughter heard her mother’s call and fell back down to the Earth. In Norse mythology, these were the goddess Freya’s hens.
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: 11/17/2025 – More about the Pleiades
This is Bob Moler with Ephemeris for Monday, November 17th. Today the Sun will be up for 9 hours and 29 minutes, setting at 5:12, and it will rise tomorrow at 7:44. The Moon, 3 days before new, will rise at 6:16 tomorrow morning.
Around 8 in the evening the marvelous small star group called the Pleiades, or Seven Sisters will be in the eastern sky. Most people can see six stars, but they’re called the Seven Sisters, so the story has come up about the Lost Pleiad. It was said that her star was dimmed because she married a mere mortal. In Greek mythology the Pleiades were the daughters of the god Atlas and Pleione. By 9 PM the hunter Orion is rising in the east to chase the Pleiades across the sky until dawn. The word Pleiades is related to the Greek word for sail, and in ancient times the sailing season in the Mediterranean Sea started with the heliacal * rising of the Pleiades at dawn in mid-spring.
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.
* Heliacal Rising – The first appearance in the morning of a celestial body after disappearing in evening twilight.
Addendum
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