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Ephemeris: 12/19/2024 – Jupiter is our bright evening Christmas star but what about 7 BC?
This is Bob Moler with Ephemeris for Tuesday, December 19th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:04, and it will rise tomorrow at 8:16. The Moon, at first quarter today, will set at 1:06 tomorrow morning.
This year Jupiter is our bright evening Christmas star. 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 BC there was a rare event over 8 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 then sent them to Bethlehem. It is thought that Pisces was associated with the Hebrews, Jupiter with the Messiah or world ruler, and Saturn with the peoples of Palestine.
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
The normal motion of the sun, moon and planets in the sky is to the east, or to the left in this diagram. Jupiter takes a bit less than 12 years to orbit the sun while Saturn takes a bit less than 30 years, so Jupiter will pass Saturn about every 20 years. However, when they are both at opposition of the sun when they do that and closest to the earth, they will appear to move backwards for a time. This is called retrograde motion from their normal eastward motion. Jupiter being closest to us and closer to the Earth’s speed makes a bigger retrograde loop than Saturn does. So when they’re both at opposition when they cross paths we get a triple conjunction like this.
12/20/2022 – Ephemeris – Hunting for the Star of Bethlehem: When did Herod the Great Die – Part 1
This is Ephemeris for Tuesday, December 20th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:04, and it will rise tomorrow at 8:16. The Moon, 3 days before new, will rise at 6:20 tomorrow morning.
In looking for the year Jesus was born and the appearance of the Star of Bethlehem, we look to the latter years of Herod the Great’s reign. Jewish historian Josephus recounts that Herod died shortly after an eclipse of the Moon occurred. The date of that eclipse, according to many historians, was March 13th, of 4 BCE and before Passover, a month later. The Greek text of Matthew states that Herod’s visitors, looking for the newborn King of the Jews, were Magi. Magi were priest-astrologers of the Zoroastrian Religion of Persia. That being the case, the Star could have been the triple conjunction of Jupiter and Saturn against the constellation of Pisces, when three times Jupiter passed Saturn between the end of May and early December of 7 BCE.
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
The Jupiter-Saturn triple conjunction of 7 BC. Click on the image to enlarge and animate. This animation is at 5-day intervals. The conjunctions took place against the stars of Pisces the fish, a constellation thought, in those days, to be associated with the Jews. The Moon will be popping in and out of the view. It ends in February of 6 BC, when Mars and the Moon enters the picture. Click on the image to enlarge it. Created using Cartes du Ciel and GIMP.
Above is an animation of the triple conjunction of Jupiter and Saturn of 7 BCE in 5 day steps. The body popping in and frame is the Moon. The first conjunction was on May 29th. Both planets stopped their eastward motion around July 6th. Astrologically, they became stationary and began their westward or retrograde motion. The second conjunction was on October 11th. Both planets stopped their westward or retrograde motion on November 1st. Again they were stationary to resume their normal eastward motion. The third and last conjunction was on December 8th. Two months later, on February 21st, of 6 BCE, Mars joined the group as they all move off to the western sky in the evening. Using this triple conjunction as the Star of Bethlehem, Jesus would have been born in the late autumn of 7 BCE or early winter of 6 BCE.
This lunar eclipse candidate for the eclipse that heralded the death of Herod the Great, and the favorite, since the time of Johannes Kepler, is the lunar eclipse of March 13, 4 BCE. It was a partial eclipse, only visible in the predawn hours. This eclipse occurred one lunar month before Passover.
Too little time for all the events Josephus describes. A better lunar eclipse occurred a bit less than three years later. Those defending the 4 BCE eclipse sometimes suggest that the Passover mentioned by Josephus was the next year’s Passover of 3 BCE. If it was the next year’s Passover, why mention Passover at all?
Tomorrow I’ll take a break to look to the naked eye planets, and to the winter solstice. Winter begins tomorrow! Thursday I’ll look to a better lunar eclipse and begin to explore another Bethlehem Star candidate.
10/24/2022 – Ephemeris – Finding Pisces the fish
This is Bob Moler with Ephemeris for Monday, October 24th. Today the Sun will be up for 10 hours and 33 minutes, setting at 6:43, and it will rise tomorrow at 8:11. The Moon, 1 day before new, will rise at 8:18 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 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. The right or western end of Pisces is the asterism, or informal constellation, of the Circlet. A loop of 5 stars, the rope around the tail of one of the fish, or the fish itself. Jupiter is seen against the stars of Pisces in the evening, the rest of this and early next year.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.
Addendum
Pisces finder animation looking south-southeast with Jupiter at 9 pm tonight, October 24, 2022. Created using Stellarium and GIMP.
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