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Ephemeris: 01/28/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, January 28th. Today the Sun will be up for 9 hours and 39 minutes, setting at 5:45, and it will rise tomorrow at 8:05. The Moon, 3 days past first quarter, will set at 5:43 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 southwestern sky as soon as it gets dark. In a telescope Saturn sports a very thin ring, 2 degrees from being edge on and is slowly opening. Jupiter is the brilliant star-like object in the eastern sky, to the right of Pollux in the pair Castor and Pollux, the bright stars of Gemini. It is still moving slowly to the west, and will, until it stops and reverses its track on March 10th. Jupiter’s 4 brightest moons can be seen even in binoculars, if held steadily enough. They shift position night to night. At 8 PM tonight, all four Galilean moons can be seen, though two may too close to the planet to be picked out in binoculars.
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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Ephemeris: 01/21/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, January 21st. Today the Sun will be up for 9 hours and 23 minutes, setting at 5:36, and it will rise tomorrow at 8:11. The Moon, 3 days past new, will set at 8:53 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 west-southwestern sky as soon as it gets dark. At 8 PM, it is in roughly in the same direction as the Moon, but a good deal higher in the sky. In a telescope Saturn sports a very thin ring, 1.8 degrees from being edge on and is slowly opening. Jupiter is the brilliant star-like object in the eastern sky, to the right of Pollux in the pair Castor and Pollux, the bright stars of Gemini. Jupiter’s 4 brightest moons can be seen even in binoculars, if held steady enough. They shift position night to night. At 8 PM tonight, only three will be visible, but the 4th will be appearing from in front of Jupiter later this evening.
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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Ephemeris: 01/20/2026 – What’s happening inside the Great Orion Nebula
This is Bob Moler with Ephemeris for Tuesday, January 20th. Today the Sun will be up for 9 hours and 21 minutes, setting at 5:35, and it will rise tomorrow at 8:12. The Moon, 2 days past new, will set at 7:42 this evening.
The closest star nursery to us, places where stars are being born, is the Great Orion Nebula, 1,300 light years away. A light year is about 6 trillion miles, if you want to pace it out. It’s located in the constellation Orion’s sword that hangs below his belt. It is seen in as little as a pair of binoculars, and shines by emission and reflection of the light of a tiny clutch of four stars at its heart, called the Trapezium. These extremely hot young massive stars are not destined to live long. Unlike the Sun’s 10 billion year lifetime, these stars lifespans will be measured in millions of years. Yet do not mourn for them, even now stars are forming within their dusty cocoons in the nebula. The Trapezium stars’ deaths will provide heavy elements for new stars and planets.
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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
There are several videos produced by NASA, ESA and others of a fanciful trip through the Great Orion Nebula. I found them by typing: NASA trip through the Orion nebula into my Internet browser.
Ephemeris: 01/16/2026 – Comparing Orion’s two brightest stars
This is Ephemeris for Friday, January 16th. Today the Sun will be up for 9 hours and 13 minutes, setting at 5:29, and it will rise tomorrow at 8:15. The Moon, 2 days before new, will rise at 7:54 tomorrow morning.
Orion’s two brightest stars are kind of the same but different. Let me explain. Betelgeuse is a red giant star, extremely massive, maybe 14 to 19 times the sun’s mass. It is somewhere between 8 and 14 million years old, which compared to the sun is just a baby, except it is so massive that it is in the last million or so years of its life. Rigel is a bluish white and a bit more massive, about 21 times the mass of the sun, and maybe 8 million years old. It has used most of the hydrogen in its core, and is beginning to transition into its final years which is a few more millions of years. So it’s not as far along in its evolution as Betelgeuse and has not bloated out and turned red. Betelgeuse is 500 light years away, while Rigel is almost 900.
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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Ephemeris: 01/14/2026 – Only two naked-eye planets are visible this week, both in the evening
This is Ephemeris for Wednesday, January 14th. Today the Sun will be up for 9 hours and 10 minutes, setting at 5:27, and it will rise tomorrow at 8:16. The Moon, halfway from last quarter to new, will rise at 6:14 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 southwestern sky as soon as it gets dark. In a telescope Saturn sports a very thin ring, 1½ degrees from being edge on and is slowly opening. Jupiter is now officially an evening planet, rising before sunset. It’s seen in the evening to the right of Pollux in the pair Castor and Pollux, the bright stars of Gemini. Jupiter’s four brightest moons can be seen even in binoculars, and shift position night to night. Jupiter can still be seen in the morning sky. At 7 AM it will be low in the western sky. Venus, Mercury and Mars are too close to the direction of the Sun to be seen.
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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Ephemeris: 01/13/2026 – Orion is too preoccupied to notice Lepus the hare
This is Ephemeris for Tuesday, January 13th. Today the Sun will be up for 9 hours and 8 minutes, setting at 5:26, and it will rise tomorrow at 8:17. The Moon, 3 days past last quarter, will rise at 5:13 tomorrow morning.
Orion, the central winter constellation is seen in the southern sky this evening. He is a hunter, as artists depict him, however, he is preoccupied with the charge of Taurus the bull from the upper right. At Orion’s feet, and unnoticed by him is the small constellation of Lepus the hare. It’s very hard to see a rabbit in its dim stars: however, I can see a rabbit’s head ears and shoulders. A misshapen box is the head and face of this critter facing to the left. His ears extend upwards from the upper right star of the box, and they bend forward a bit. Two stars to the right of the box and a bit farther apart hint at the front part of the body. Others see a whole rabbit facing the other direction, with additional stars to depict his long ears.
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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Ephemeris: 01/12/2026 – How to find the twins of Gemini
This is Ephemeris for Monday, January 12th. Today the Sun will be up for 9 hours and 6 minutes, setting at 5:24, and it will rise tomorrow at 8:17. The Moon, 2 days past last quarter, will rise at 4:08 tomorrow morning.
Another famous winter constellation is Gemini. The constellation of Gemini the Twins is visible halfway to the zenith in the east, at the top and left of Orion the hunter, at 9 pm. The namesake stars of the two lads, are the two bright stars at the left end of Gemini, and are high and are due east. Castor is on top, while Pollux is below. From them come two lines of stars that outline the two, extending horizontally toward Orion. Currently, Jupiter in its retrograde motion is situated level with Pollux at 9 PM. Pollux is left of the much brighter Jupiter. In Greek mythology the Gemini twins were half brothers, Castor was fathered by a mere mortal, while Pollux was fathered by Zeus, but were born together as twins. When Castor was killed during the quest for the Golden Fleece, Pollux pleaded with Zeus to let him die also, so Zeus placed them together in 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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Ephemeris: 01/08/2026 – The star named “Before the Dog”
This is Ephemeris for Thursday, January 8th. Today the Sun will be up for 9 hours even, setting at 5:20, and it will rise tomorrow at 8:19. The Moon, 2 days before last quarter, will rise at 11:45 this evening.
After 8 o’clock this evening look to the southeastern sky for the Orion the hunter constellation. Below into the left of it are two very bright stars. The one below is Sirius also known as the Dog Star, in the heart of Canis Major, the Great Dog, which is still rising at 8. Above and to the left of it is a star called Procyon which is the heart of Orion’s little dog, Canis Minor. The name Procyon is from the Greek meaning Before the Dog. The reason for Procyon’s name is the fact that it, though east of Sirius, rises before it. All things being equal, Sirius should rise before Procyon. The reason is, viewing from the Northern Hemisphere Procyon is north of Sirius, and stays out longer. It is far enough north and not that far to the east of Sirius, that it can rise before Sirius or before the Dog… Star.
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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Ephemeris: 01/07/2026 – Taking our first weekly look at the whereabouts of the naked-eye planets for 2026
This is Ephemeris for Wednesday, January 7th. Today the Sun will be up for 8 hours and 59 minutes, setting at 5:19, and it will rise tomorrow at 8:19. The Moon, 3 days before last quarter, will rise at 10:37 this evening.
Let’s take our first weekly look at the whereabouts of the naked-eye planets for 2026. Saturn is the brightest star-like object in the southwestern sky as soon as it gets dark. In a telescope Saturn sports a very thin ring, 1.2 degrees from being edge on and is slowly opening. Jupiter will rise just after sunset. It is seen in the evening right of Pollux in the pair Castor and Pollux, the bright stars of Gemini. The giant planet is slowly moving westward with its retrograde motion. Jupiter’s 4 brightest moons can be seen even in binoculars, and shift position night to night. In the morning sky, only Jupiter can be seen. It will leave the morning sky, become an official evening planet Saturday. Venus crossed behind the Sun yesterday to become an evening planet. Mars will also cross behind the Sun Friday to become a morning planet.
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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Ephemeris: 01/06/2026 – A river in the sky
This is Ephemeris for Tuesday, January 6th. Today the Sun will be up for 8 hours and 58 minutes, setting at 5:18, and it will rise tomorrow at 8:19. The Moon, 3 days past full, will rise at 9:25 this evening.
One of the more obscure constellations around is Eridanus, which depicts a river. At 8 PM the river, marked by dim stars, starts near the lower right corner of Orion, near the bright star Rigel and flows to the right then down a little way, then to the lower left, and again to the right, to the southern horizon. One has to travel to the far south to see the southern terminus of the river, the bright star Achernar. Writers over the ages have seen here the Nile, the Rhine and the Earth circling river Ocean of the flat earth days. To most Greeks, including Ptolemy it was simply the River. The earlier Greek astronomer Hipparchus called it the River of Orion, alluding to Orion’s star Rigel as its source. The southern part of the river was added when astronomers made it far enough south.
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; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.
Addendum
Bob Moler's Ephemeris Blog 