Ephemeris: 01/28/2026 – Taking our weekly look at the whereabouts of the naked-eye planets

January 28, 2026 Comments off

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

Saturn appears lonely in the west- southwestern sky at 8 PM.
Saturn appears lonely in the west- southwestern sky at 8 PM. Created using Stellarium.
Jupiter as it appears tonight, January 28, 2026, in its orientation at 9:00 PM, moving against the stars of Gemini. Also shown is its track from last July to next July, and the retrograde loop that is currently making.
Jupiter as it appears tonight, January 28, 2026, in its orientation at 9:00 PM, moving against the stars of Gemini. Also shown is its track from last July to next July, and the retrograde loop that is currently making, slowly moving to the West which you will do for the next 41 days until it stops in March. Then it will resume its eastward motion. Created using Stellarium, Libreoffice Draw and GIMP.
The Moon three days past first quarter, as seen this evening, January 28, 2026. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Saturn, and Jupiter (north up) as they would be seen in a small telescope with the same magnification at 8 PM tonight.
Telescopic Saturn, and Jupiter (north up) as they would be seen in a small telescope with the same magnification at 8 PM tonight, January 28, 2026. Saturn will be 16.4″ in diameter, but its rings, being nearly edge on, may show up brighter than seen here, and extend to 38.2″. They are tilted 2.0° from being edge on. Jupiter will be 45.9″ in diameter. Io will begin transiting the planet at 8:35 PM EDT (1:35 UT on the 29th). Its shadow will begin crossing the planet at 9:02 PM EDT (2:02 UT). The transit will end at 10:51 PM EDT (3:51 UT), with the shadow leaving the planet at 11:19 PM EDT (4:19 UT). The (”) symbol means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts), LibreOffice Draw and GIMP.
The naked-eye planets and the Moon at sunset and sunrise on a single night.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on January 28th, 2026. The night ends on the left with sunrise on the 29th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, January 28th and 29th, 2026. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

Ephemeris: 01/27/2026 – Orion’s heat shield problem

January 27, 2026 Comments off

This is Ephemeris for Tuesday, January 27th. Today the Sun will be up for 9 hours and 37 minutes, setting at 5:44, and it will rise tomorrow at 8:06. The Moon, 2 days past first quarter, will set at 4:29 tomorrow morning.

One of the problems that was detected with the reentry of the Artemis 1 mission back in November 2022* was the degradation of the heat shield of the Orion capsule. Chunks of the heat shield actually were breaking off. The technique they use for reentry called the skip reentry was thought to be the culprit. So while they are attempting to redesign the heat shield, Artemis 2 will be using the same type heat shield, but they will not do a skip reentry and come in without a skip off the atmosphere. The reason for using a skip reentry is to lessen the amount of Gs that are pulled by the capsule coming in at 7 miles per second by prolonging the entry and increasing the downrange travel of the capsule. Skip reentry is a proven technique, the Russians have been doing it for decades.

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.

* For the broadcast, I misremembered the date as December 2024. That’s what happens when you’re old.

Addendum

Heat shield damage from the Artemis 1 reentry. :Credit: NASA.
Heat shield damage from the Artemis 1 reentry. :Credit: NASA.
Lunar entry modes, skip entry vs. direct entry. Credit: NASA.
Lunar entry modes, skip entry vs. direct entry. Credit: NASA.

Ephemeris: 01/26/2026 – Artemis, not just flags and footprints

January 26, 2026 Comments off

This is Ephemeris for Monday, January 26th. Today the Sun will be up for 9 hours and 35 minutes, setting at 5:43, and it will rise tomorrow at 8:07. The Moon, 1 day past first quarter, will set at 3:10 tomorrow morning.

The current space race or I might say more properly, Moon race, is more than it was in the 1960s this race is not simply what is called a flag and footprints race get there first and go home. We already did that 57 years ago. But to set up permanent settlements on the moon to explore and extract the Moon’s resources like water. Water is not for export. Whatever water we find on the Moon would still be fairly scarce and probably rationed. There’s also an unknown amount of helium 3, which is a useful fuel for fusion reactors. Something we don’t have on the Earth, but would be the Holy Grail for clean energy production. We don’t know the Moon’s mineral potential, but whatever we find won’t have to be hauled up a quarter of a million miles from the Earth.

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

An artist's impression of what a moon base might look like.
An artist’s impression of what a moon base might look like. Credit: ESA (European Space Agency).

Ephemeris: 01/23/2026 – The new space race

January 23, 2026 Comments off

This is Ephemeris for Friday, January 23rd. Today the Sun will be up for 9 hours and 28 minutes, setting at 5:39, and it will rise tomorrow at 8:09. The Moon, 2 days before first quarter, will set at 11:17 this evening.

In the 1960s The United States and the Soviet Union engaged into what was called the space race. A race that was essentially to be the first nation to set foot on the Moon. It was a race the United States won when Neil Armstrong set foot on the Moon on July 20th 1969. We are now engaged in another space race, this time with China. It looks like Russia is sitting this one out, or are helping the Chinese, though it looks like the Chinese are out innovating them with their own reusable rockets. The stakes are higher this time. There is a place on the Moon in which everyone is interested. That being the Moon’s South Pole which has water in the form of ice in permanently shadowed craters, which would be worth its weight in gold.

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

A 1/10th scale model of the China's Long March 10 rocket, purported to be their Moon Rocket.
A 1/10th scale model of the China’s Long March 10 rocket, purported to be their Moon Rocket. It is supposed to be ready for a human landing attempt on the Moon by 2030. Credit: Shujianyan.

Ephemeris: 01/22/2026 – Artemis II launch window opens up in 15 days

January 22, 2026 Comments off

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

Artemis 2 planned a trajectory out around the Moon and back.
Artemis 2 planned a trajectory out around the Moon and back. Click or tap on the image for a larger more readable size.Credit: NASA.
Apollo 8 (AS-503) Lunar Mission Sequence Orbital Mission.
Apollo 8 (AS-503) Lunar Mission Sequence Orbital Mission. Credit: NASA.
Earth-Moon distance and sizes to scale.
Earth-Moon distance and sizes to scale. The white blob in the center right is supposed to be a light pulse. Click or tap on the image for a larger view. Credit: NASA.

Ephemeris: 01/21/2026 – Taking our weekly look at the whereabouts of the naked-eye planets

January 21, 2026 Comments off

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

Saturn and the waxing crescent Moon as they might appear tonight.
Saturn and the waxing crescent Moon as they might appear tonight, January 21, 2026. The Moon is being enlarged by a factor of 2 to show it up better. Look off into the west southwest at 8:00 PM. Created using Stellarium.
Jupiter as it appears tonight in its orientation at 8:00 PM, moving against the stars of Gemini. Also shown is its track from last July to next July, and the retrograde loop that is currently making.
Jupiter as it appears tonight, January 21, 2026, in its orientation at 8:00 PM, moving against the stars of Gemini. Also shown is its track from last July to next July, and the retrograde loop that is currently making, slowly moving to the West which you will do for the next 48 days until it stops in March. Then it will resume its eastward motion. Created using Stellarium, Libreoffice Draw and GIMP.
The Moon three days past new, as seen this evening, January 21, 2026. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Saturn, and Jupiter (north up) as they would be seen in a small telescope with the same magnification at 8 PM tonight.
Telescopic Saturn, and Jupiter (north up) as they would be seen in a small telescope with the same magnification at 8 PM tonight, January 21, 2026. Saturn will be 17.0″ in diameter, but its rings, being nearly edge on, may show up brighter than seen here, and extend to 38.6″. They are tilted 1.8° from being edge on. Jupiter will be 46.3″ in diameter. The (”) symbol means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts), LibreOffice Draw and GIMP.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on January 21st, 2026. The night ends on the left with sunrise on the 22nd.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on January 21st, 2026. The night ends on the left with sunrise on the 22nd. Mercury is not plotted, being too close to, and south of the Sun. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, January 21st and 22nd, 2026.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, January 21st and 22nd, 2026. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

Ephemeris: 01/20/2026 – What’s happening inside the Great Orion Nebula

January 20, 2026 Comments off

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

The lower part of Orion with the Great Orion Nebula. Created using Stellarium.
The lower part of Orion with the Great Orion Nebula. Created using Stellarium.
The Sword of Orion, with the Great Orion Nebula and other nebulae in the sword.
The Sword of Orion, with the Great Orion Nebula and other nebulae in the sword oriented to approximate the image above. To the naked eye, the center star of the sword may appear just as a single star. However, in binoculars a glow might be visible among several stars there. In a telescope, using its very lowest power, some structure might be visible that shows up in this photograph as the brightest part of the nebula, and the blue wisps downward and to he upper right of the brightest part. The main part of the nebula was catalogued by Charles Messier in the 18th century as M42, the 42nd object on his catalog of things in the sky that weren’t comets. That little bit of brightness just above left of center of it he cataloged as a separate nebula, M43. In fact, all this nebulosity belongs to one great molecular cloud. Credit: Daniel Dall’Olmo.

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!

January 19, 2026 Comments off

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

Shown are the positions of the Big and Little Dippers in relation to Polaris, the North Star in the evening sky, early in each season.
Shown are the positions of the Big and Little Dippers in relation to Polaris, the North Star in the evening sky, early in each season. The dippers themselves, even though there are four sets of them, are in the same quadrant defined by the pointer arrows, and that dippers seem to pour into each other. Created using my LookingUp app, GIMP and LibreOffice Draw.

Ephemeris: 01/16/2026 – Comparing Orion’s two brightest stars

January 16, 2026 Comments off

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

Orion's named stars
Orion’s named stars. Betelgeuse means “Armpit”. Bellatrix means “Female warrior”. The names of the belt stars refer to belt or girdle, Rigel refers to Orion’s foot. Saiph means sword, however Orion’s sword is the line of three stars below the belt stars. In binoculars, there’s more than three stars here. Around the second “star” of the sword is the Great Orion Nebula, barely visible here. Created using Stellarium.
Betelgeuse disk
This is the disk of the star Betelgeuse in Orion. It is not an image from an optical telescope, but of an image created in submillimeter microwaves by the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. Color added for your viewing pleasure. Credit: ALMA (ESO/NAOJ/NRAO)/E. O’Gorman/P. Kervella
Rigel A & B
Rigel with its companion star as photographed through a telescope. No attribution. Source: http://washedoutastronomy.com/content/urban-orion?page=1

Ephemeris: 01/15/2026 – Orion’s great cloud

January 15, 2026 Comments off

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

Orion is lousy with gas and dust. A regular star factory, or nursery. The red nebulae shows the predominance of hydrogen in here. The white nebulosity to the right of Rigel is the Witches Head nebula, probably the reflection of Rigel’s light off a dust cloud. Base image by Bernal Andreo, via Wikipedia.
The Great Orion Nebula
The Great Orion Nebula, the birthplace of stars, along with some dark dusty nebulae. Credit: Daniel Dall’Olmo
Inner part of the Great Orion Nebula. Image by Scott Anttila
Inner part of the Great Orion Nebula, including the four stars of the Trapezium. Image by Scott Anttila