Archive
Ephemeris: 01/22/2026 – Artemis II launch window opens up in 15 days
This is Ephemeris for Thursday, January 22nd. Today the Sun will be up for 9 hours and 26 minutes, setting at 5:37, and it will rise tomorrow at 8:10. The Moon, 3 days before first quarter, will set at 10:04 this evening.
The launch window for the first crewed Artemis mission to the Moon opens up in a bit more than two weeks. It is made-up of 3 approximately 2 week windows containing four or five possible launch dates that extend to April. This mission is a mission to simply loop around the Moon and come back. It is different from the Apollo 8 mission, that actually orbited the Moon 10 times before returning to the Earth. The four astronauts will become the farthest members of humanity to venture from the Earth. One has hoped that NASA has solved the hydrogen leak problem that plagued the Artemis 1 mission a bit more than a year ago. Hydrogen is a small molecule that can leak through just about anything.
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: 01/19/2026 – Follow the drinkin’ gourd!
This is Bob Moler with Ephemeris for Martin Luther King Jr. Day, Monday, January 19th. Today the Sun will be up for 9 hours and 19 minutes, setting at 5:33, and it will rise tomorrow at 8:13. The Moon, 1 day past new, will set at 6:30 this evening. | This day is set aside to honor the Reverend Dr. Martin Luther King Jr. who gave his life for the struggle for equality for blacks and other minorities and to end segregation. A struggle that continues to this day. In the decades before the Civil War runaway slaves would travel, often at night, northward from the slave states of the south to the northern free states and Canada over the metaphorical Underground Railroad. They followed the Drinking Gourd, the Big Dipper as their compass. Over the last several millennia the Great Bear, Ursa Major had been that northward pointer. For the past few millennia the North Pole of the sky had been passing near the handle of the Big Dipper or bear’s tail. Though the Big Dipper isn’t always north, the two stars at the front of the bowl, or gourd, point to the star Polaris, which is nearly at the true North Pole of 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: 01/15/2026 – Orion’s great cloud
This is Ephemeris for Thursday, January 15th. Today the Sun will be up for 9 hours and 12 minutes, setting at 5:28, and it will rise tomorrow at 8:15. The Moon, 3 days before new, will rise at 7:09 tomorrow morning.
The brightest interstellar cloud visible in our skies is the Great Orion Nebula. The word nebula is from the Latin “nebulum” for cloud. The constellation of Orion is filled with nebulae, most of it are dim or dark. The Great Orion Nebula is in Orion’s sword. The sword is what looks like three stars that look dimmer than the three belt stars hanging from the belt. There are actually more than three stars here. Around the stars that appear as the center of the sword stars, to the eye, can be seen a haze in binoculars. A telescope with a wider aperture and low power can see detail in the cloud. With more magnification, a clutch of four baby stars can be spotted in the brightest part of the nebula. They light up the nebula and are called the Trapezium.
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: 01/09/2026 – Mars is behind the Sun today
This is Bob Moler with Ephemeris for Friday, January 9th. Today the Sun will be up for 9 hours and 2 minutes, setting at 5:21, and it will rise tomorrow at 8:18. The Moon, 1 day before last quarter, will rise at 12:51 tomorrow morning.
Mars is in conjunction with the Sun today. That means that it is behind the Sun, and it will enter our morning sky so that the Earth can be in an approximately 13 month pursuit of Mars for the next opposition. This is the center of a two-week period where communication with our satellites and Rovers on Mars is disrupted by the Sun which is a great generator of radio noise. Our radio telescopes on the Earth can hear transmissions from these assets on Mars a lot better than they can hear transmissions from the Earth. Just before conjunction we apparently have lost the Maven satellite that investigated the atmosphere of Mars, and helped relay communications from the rovers Perseverance and Curiosity.
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
Distances to the solar system objects above
The Sun: 91.3 million miles, 147.1 million kilometers
Venus: 159.0 million miles, 255.0 million kilometers
Mars 223.3 million miles, 360.0 million kilometers
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
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