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Ephemeris: 12/22/2025 – The most popular astronomical explanation for the Star of Bethlehem
This is Ephemeris for Monday, December 22nd. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:05, and it will rise tomorrow at 8:18. The Moon, 3 days past new, will set at 7:30 this evening.
This year we have a bright evening Christmas star, Jupiter in the east. But what about the one described in the Bible, in the Gospel of Matthew? We will look today at the first of two events that may have been recorded as the Star of Bethlehem. In 7 BCE there was a rare event over 6 months when three times the planet Jupiter passed Saturn against the stars of the constellation Pisces. Could the Persian astrologer priests, called Magi, have read into the event enough significance to start the journey to Jerusalem in search of the newborn King of the Jews? It was the scribe’s readings that sent them to Bethlehem. Jupiter, Saturn and Pisces all may have had significance to the Magi.
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: 09/26/2025 – Pegasus rising
This is Ephemeris for Friday, September 26th. Today the Sun will be up for 11 hours and 56 minutes, setting at 7:32, and it will rise tomorrow at 7:36. The Moon, 3 days before first quarter, will set at 9:19 this evening.
Saturn is well up in the east southeastern sky at 10 PM. This is the brightest “star” in that direction. Below it, at about the 4 o’clock position from it is Fomalhaut, which I sometimes call the loneliest star in the sky, because without Saturn or another planet in that direction it seems pretty much alone low in the south. Above and a bit to the left of Saturn is the Great Square of Pegasus A four star group standing on one corner which is the body of Pegasus the flying horse. Between Saturn and the Great Square is a faint and small circle of five or six stars called the Circlet, an asterism, which is a loop around one of the fish of Pisces the fish. Pisces is two fish held together by a long rope.
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: 12/23/2024 – What was the Star of Bethlehem? Part 1
This is Ephemeris for Monday, December 23rd. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:06, and it will rise tomorrow at 8:18. The Moon, 1 day past last quarter, will rise at 2:05 tomorrow morning.
The most popular solution to what the Star of Bethlehem may have been, is a triple conjunction of Jupiter and Saturn that occurred in 7 BCE, where Jupiter passed Saturn three times in a few months time. So the event should more probably be called a celestial sign, rather than a star. The conjunction occurred against the constellation of Pisces the fish which was thought to represent the Jews or whoever lived in that area. Such a series of conjunctions against a particular zodiacal constellation would occur only about once every 800 to 900 years. Triple conjunctions aren’t super rare, if you don’t care which constellation it’s happening in front of. We had one in 1981, but it was against the constellation of Virgo.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
12/20/2021 – Ephemeris – Could the Star of Bethlehem have been a triple conjunction of Jupiter and Saturn in 7 BCE?
This is Ephemeris for Monday, December 20th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:04, and it will rise tomorrow at 8:17. The Moon, 2 days past full, will rise at 6:12 this evening.
This year we have two bright evening Christmas stars, Venus and Jupiter. But what about the one described in the Bible, in the Gospel of Matthew? We will look today at the first of two events that may have been recorded as the Star of Bethlehem. In 7 BCE there was a rare event over 6 months when three times the planet Jupiter passed Saturn against the stars of the constellation Pisces. Could the Persian astrologer priests, called Magi, have read into the event enough significance to start the journey to Jerusalem in search of the newborn King of the Jews? It was the scribe’s readings that sent them to Bethlehem. Jupiter, Saturn and Pisces all may have had significance to the Magi.
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
Jupiter and Saturn pass each other three times from May to December in 7 BC. Created using Cartes du Ciel (Sky Charts) and GIMP.
This timing of the Star is based on the Jewish historian Josephus, dating the death of Herod the Great just before a lunar eclipse. The eclipse most historians accept was the one on March 13, 4 BCE. So Jesus could have been born in 6 BCE.
I have been giving a presentation to the Grand Traverse Astronomical Society every other December since the 1980s on the Star of Bethlehem, tweaking it each time, and completely rewriting it a few times. Below is my script from my 2020 program In Search of the Star of Bethlehem for the Grand Traverse Astronomical Society. It has small thumbnails of the slides. The name says notes, but it evolved into a complete script, and is laid out to be read that way.
Star of Bethlehem 2020 Notes (PDF)
In the presentation, I cover another possibility for the “Star”, which I happen to like more. I’ll talk about that on Christmas Eve. If you can’t wait, check out the PDF, or a prior December program in the Archives.
10/19/2020 – Ephemeris – This zodiacal constellation seems fishy
This is Bob Moler with Ephemeris for Monday, October 19th. Today the Sun will be up for 10 hours and 46 minutes, setting at 6:50, and it will rise tomorrow at 8:05. The Moon, 3 days past new, will set at 8:58 this evening.
High in the southeast at 9 p.m. are the four bright stars of the Great Square of Pegasus, the upside down flying horse. Lying along the left and bottom sides of the great square is the constellation of Pisces the fish, one of the 12 constellations of the Zodiac. Even though the constellation is called the fish, the fish themselves are not well represented in the stars. What can be traced in the stars is the rope, that’s tied to their tails, anchored at the extreme southeastern part of the constellation that is seen in the stars. It is near where the bright red planet Mars currently is. The right or western end of Pisces is the asterism, or informal constellation, of the Circlet. It’s the loop of 5 stars, the rope around the tail of one of the two fish.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Pisces finder animation showing the Great Square of Pegasus as a way to find it, though this year bright Mars will show where it is. Created using Stellarium and GIMP.
Mars’ apparent path for the rest of 2020 stays within Pisces. Mars doesn’t do a loop de loop as the ancients thought when they thought the Earth was motionless. It’s the effect of the Earth passing Mars in their orbits. Mars will stop its westward or retrograde motion around November 13th and resume its normal eastward motion. This view created using Cartes du Ciel (Sky Charts).
10/25/2019 – Ephemeris – Finding Pisces the fish
Ephemeris for Friday, October 25th. Today the Sun will be up for 10 hours and 31 minutes, setting at 6:42, and it will rise tomorrow at 8:12. The Moon, 2 days before new, will rise at 6:00 tomorrow morning.
High in the southeast at 9 p.m. are the four bright stars of the Great Square of Pegasus, the upside down flying horse. Lying along the left and bottom sides of the great square is the constellation of Pisces the fish, one of the 12 constellations of the Zodiac that lie along the path of the sun, moon and planets. Even though the constellation is called the fish, the fish themselves are not well represented in the stars. What can be traced in the stars is the rope, that’s tied to their tails, anchored at the extreme southeastern part of the constellation that is seen in the stars. The right or western end of Pisces is the asterism, or informal constellation, of the Circlet. It’s the loop of 5 stars, the rope around the tail of one of the two fish.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Pisces finder animation for 9 p.m. tonight October 25, 2019. Created using Stellarium and GIMP.
11/21/2017 – Ephemeris – The constellation of the fish has me looking for the fish
Ephemeris for Tuesday, November 21st. The Sun will rise at 7:47. It’ll be up for 9 hours and 21 minutes, setting at 5:09. The Moon, 3 days past new, will set at 7:50 this evening.
High in the south at 8 or 9 p.m. are the four bright stars of the Great Square of Pegasus, the upside down flying horse. Lying along the left and bottom sides of that square is the constellation of Pisces the fish, one of the 12 constellations of the Zodiac that lie along the path of the sun, moon and planets. Even though the constellation is called the fish, the two fish themselves are not represented in the stars, at least that’s how I see it. What can be traced in the stars is the rope, that’s tied to their tails, anchored at the extreme southeastern part of the constellation. The right or western end of the Pisces is the asterism, or informal constellation, of the Circlet. It’s the loop of 5 stars, the rope around the tail of one of the two fish. The other end, without a loop, ends up under Andromeda. Artists have always supplied the fish.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Animated Pisces finder chart base at November 21, at 9 p.m. Created using Stellarium and GIMP.
11/07/2017 – Ephemeris – The autumn constellations are all visible in the early evening
Ephemeris for Election Day for some folks, Tuesday, November 7th. The Sun will rise at 7:28. It’ll be up for 9 hours and 54 minutes, setting at 5:23. The Moon, 3 days before last quarter, will rise at 8:49 this evening.
We’ll have about an hour and a half of reasonably dark skies between 6:30 and nearly 9 p.m. – At 8 p.m. all the autumn constellations are visible. The Zodiacal constellations from Capricornus in the southwest through Aquarius, Pisces and Aries, all relatively faint to Taurus rising in the east northeast. Pegasus the flying horse is seen in the high south-southeast. It and the connected constellation of Andromeda the chained princess are seen above Aquarius through Aries. The bright star Fomalhaut holds a lonely vigil low in the south, High in the northeast is the W shaped constellation of Cassiopeia the queen, under which is Perseus, her son-in-law and hero down to the bright star Capella.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
The sky at 8 p.m. November 7, 2017 showing the autumn constellations, centered on the southeastern sky. Click on the image to enlarge. The Milky Way has been brightened to show its passage through Perseus better. The red line is the ecliptic, the path of the Sun through the Zodiac. Created using Stellarium.
Addendum
11/24/2016 – Ephemeris – The little constellation that used to start the seasonal year
Ephemeris for Thanksgiving Day, Thursday, November 24th. The Sun will rise at 7:52. It’ll be up for 9 hours and 14 minutes, setting at 5:06. The Moon, 3 days past last quarter, will rise at 3:54 tomorrow morning.
From antiquity, the first constellation of the Zodiac has been Aries the ram. That’s the constellation the Sun entered on the first day of spring, or the vernal equinox. Well that was a couple of thousand years ago. Currently the vernal equinox point is in western Pisces. This is due to the wobbling of the Earth’s axis called precession. The spinning Earth like and top or gyroscope wobbles when force is applied to it. In this case the Sun and Moon. One wobble takes 26,000 years to complete. Anyway, Aries is a small constellation of four stars in a bent line, below the triangular constellation of Triangulum, which is itself below Andromeda. It’s a bit west or right of the Pleiades or Seven Sisters star cluster.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Aries the ram animated finder chart for 9 p.m. November 24, 2016. Created using Stellarium and GIMP.
The vernal equinox today, where the blue line, the celestial equator and the orange line, the ecliptic or path of the Sun cross. The Sun is where these lines cross on the first day of spring (March 20th around here). Note that the vernal equinox is now in western Pisces. Created using Stellarium.
The vernal equinox back in AD 100, where the blue line, the celestial equator and the orange line, the ecliptic or path of the Sun cross. The Sun is where these lines cross on the first day of spring. Note that the vernal equinox was at the east edge of Pisces. Created using Stellarium.
11/21/2016 – Ephemeris – The two fishies of Pisces
Ephemeris for Monday, November 21st. The Sun will rise at 7:48. It’ll be up for 9 hours and 20 minutes, setting at 5:08. The Moon, at last quarter today, will rise at 12:54 tomorrow morning.
High in the south-southeast at 9 p.m. are the four bright stars of the Great Square of Pegasus, the upside down flying horse. Lying along the left and bottom sides of the great square is the constellation of Pisces the fish, one of the 12 constellations of the Zodiac that lie along the path of the sun, moon and planets. Even though the constellation is called the fish, the fish themselves are not represented in the stars. What can be traced in the stars is the rope, that’s tied to their tails, anchored at the extreme southeastern part of the constellation that is seen in the stars. The right or western end of Pisces is the asterism, or informal constellation, of the Circlet. It’s the loop of 5 stars, the rope around the tail of one of the two fish.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
An animation of the constellation of Pisces the fish, showing first the stars, then the constellation outline including those of Pegasus, and Aquarius, then an artist rendering. Created using Stellarium and GIMP.
I don’t care what the artists think, I still think the circlet is a loop around the western fish’s tail.
Bob Moler's Ephemeris Blog 