Archive
Ephemeris: 12/30/2024 – Two great astronomical events of 2024
This is Ephemeris for Monday, December 30th. Today the Sun will be up for 8 hours and 51 minutes, setting at 5:11, and it will rise tomorrow at 8:20. The Moon is new today, and won’t be visible.
Speaking of new moons, the most spectacular astronomical event of 2024 was the total solar eclipse of April 8th. The path of totality came fairly close to us here in Northern Michigan just clipping the southeastern corner of the state. It was my sixth observation of a total solar eclipse out of six tries and probably my last, because our next total solar eclipse in the contiguous 48 states will be twenty-one years from now in 2045. The other event of 2024 was the appearance of the Comet Tsuchinshan-ATLAS which graced our skies for a few days in mid-October. I have no reports of anybody seeing it with the naked eye, however it was visible in binoculars and easily photographed with a few seconds exposure with a camera. It had a very prominent tail.
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
Ephemeris: 12/24/2024 – Looking at another possibility for the Star of Bethlehem
This is Ephemeris for Christmas Eve, Tuesday, December 24th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:07, and it will rise tomorrow at 8:18. The Moon, 2 days past last quarter, will rise at 3:10 tomorrow morning.
Many writers of the 2nd and 3rd centuries CE place Jesus’ birth, via Roman events, around 2 BCE. So the Star of Bethlehem could appear several years later than the triple conjunction of Jupiter and Saturn in 7 BCE that’s been popular. In 3 and again in 2 BCE there were star-like conjunctions or apparent joining of the planets Jupiter and Venus against the backdrop of the constellation of Leo the Lion. A lion is related to Judah, son of Jacob, by a blessing the latter gave his 12 sons in Genesis. The first conjunction occurred in August in the morning sky. On June 16th of the next year the two planets got together again, this time in the evening sky, a month or more after Jesus would have been born in the vulnerable spring lambing season when shepherds would most likely be out at night guarding the flocks, not December 25th.
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
An edited excerpt from this year’s Star of Bethlehem presentation I gave to the Grand Traverse Astronomical Society on December 6th.
The triple conjunction of Jupiter and Saturn in 7 BCE is the generally accepted Star of Bethlehem, with Jesus being born in 6 or 5 BCE and Herod’s death being in 4 BCE after a lunar eclipse. What if the lunar eclipse in question was in 1 BCE? If so, there is that other possibility. It involves the constellation Leo, which is a lion. There is a passage in Genesis in which Jacob, who, by this time, is called Israel, is blessing his sons, each the heads of the twelve tribes of Israel. In Genesis 49 9-10 He compares him to a lion cub, the king of beasts, from whom the leaders of Israel will come. We can make a connection between Judah and the celestial lion, Leo. Let’s take a look at the celestial happenings against the constellation of Leo with Jupiter and Venus in 3 and 2 BCE.
On August 12th of 3 BCE Jupiter and Venus appeared to come together so close as to be separable only in telescopes. This may have been the Star at its rising mentioned to Herod. Could this predawn celestial mating of Jupiter, who the Babylonians saw as the god Marduk and Venus as Ishtar, the goddess of fertility, to bring forth a powerful king? The Magi, I’m pretty sure, would have known that 10 months later, a little longer than the human gestation period, by the way, that the two planets would again come together.
Ten months after the first conjunction of Jupiter and Venus, perhaps as the Magi neared Jerusalem, they saw Jupiter and Venus approaching each other again. Later as they left Herod’s palace on the evening of June 16th, 2 BCE the conjunction was at its tightest. They saw the “Star” again, as Matthew relates. Telescopes, which wouldn’t be invented for another sixteen hundred years, could have seen this extremely close conjunction of Jupiter and Venus. Venus, near its greatest eastern elongation from the Sun, would appear half illuminated. But even to the best naked eye observer, Jupiter and Venus would merge into a single star. Venus was much brighter than Jupiter than it appears here. In fact, it was nearly twelve times brighter, so Jupiter’s added brightness wouldn’t contribute much to the combined brightness. Jupiter would seem to disappear at their closest.
Also, there was a conjunction of Jupiter with the “Little King” star Regulus on September 14th 3 BCE, one or two days after the beginning of the Jewish New Year. Was this another sign that a new King of the Jews would be born? It is actually the first of three conjunctions Jupiter has with Regulus in the next 9 months. Yes, another triple conjunction. Jupiter passed Regulus the second time on February 17, of 2 BCE and for a final time on May 9th. During this time Venus had moved back toward the Sun and entered the evening sky where Jupiter met it once again.
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
Ephemeris: 06/11/2024 – The man who first mapped the Moon
This is Bob Moler with Ephemeris for Tuesday, June 11th. Today the Sun will be up for 15 hours and 31 minutes, setting at 9:28, and it will rise tomorrow at 5:56. The Moon, 3 days before first quarter, will set at 1:31 tomorrow morning.
Ever wonder where the names of the features of the Moon come from? Most of the large features on the Moon were named by Giovanni Battista Riccioli, a Jesuit priest of the 17th century. He created the first accurate map of the Moon in 1651, and he named the features he drew including the Sea of Tranquility (Mare Tranquillitatis), the craters Tycho, Plato, Clavius and many others that I talk about. Even though he professed the Earth centered universe, he gave the heliocentrists Copernicus, Kepler and Aristarchus prominent craters, but in the Ocean of Storms, Oceanus Procellarum, denoting the controversy of the day. Riccioli’s nomenclature became the standard for the Moon and other planets and moons.
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
Ephemeris: 06/06/2024 – 80 years ago, D-Day’s astronomical connection
This is Ephemeris for Thursday, June 6th. Today the Sun will be up for 15 hours and 27 minutes, setting at 9:25, and it will rise tomorrow at 5:57. The Moon is new today, and won’t be visible.
Today is the 80th anniversary of the greatest battle of World War II was the Allied invasion of Mainland Europe at Normandy on D-Day, a date governed by the phase of the Moon. The full moon on June the 6th, 1944 gave light for the gliders and paratroopers to carry out their operations at midnight. Plus the high tides were near noon and midnight and the low tides near dawn. The idea was to hit the beach at low tide to enable the landing craft to operate without hitting the obstacles the Germans had planted in the tidal zone. It was great for the landing craft, but the troops had a lot of open beach to run through to get to any sort of shelter. The best days for the invasion were the 5th, 6th and 7th of June. Bad weather on the 5th caused a one day postponement.
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
Ephemeris: 05/17/2024 – The famous Big Dipper stars Mizar and Alcor
This is Ephemeris for Friday, May 17th. Today the Sun will be up for 14 hours and 55 minutes, setting at 9:07, and it will rise tomorrow at 6:10. The Moon, 2 days past first quarter, will set at 4:01 tomorrow morning.
In tonight’s sky, the Big Dipper is nearly overhead. In its handle is a star or two that are interesting. It’s the star at the bend in the handle. It’s called Mizar. Next to it, for those with good eyesight, is a dimmer star, called Alcor. The name Mizar is from the Arabic, meaning apron or cover, while Alcor means the forgotten one. Before optometrists, the ability to actually see both stars was a test for good eyesight, especially for Arabic warriors. The pair is also known as the “Horse and the Rider”. I’ve been told that some Native American tribes saw the handle stars as hunters following the Great Bear, Ursa Major, of which the Big Dipper is a part, rather than its very unnatural tail. Dim Alcor became a hunting dog.
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
Ephemeris: 04/15/2024 – How the Ancient Greeks tried to measure the distance to the Sun
This is Bob Moler with Ephemeris for Monday, April 15th. Today the Sun will be up for 13 hours and 31 minutes, setting at 8:28, and it will rise tomorrow at 6:55. The Moon, at first quarter today, will set at 4:15 tomorrow morning.
The first quarter Moon tonight reminds me of how the Greeks used the quarter Moon to attempt to determine the distance to the Sun. The idea was to determine when the Moon was exactly at first or last quarter, so the angle of the Sun-Moon-Earth was exactly 90°. The next thing to do was to measure the actual angle between the Sun and the Moon at that instant. It’s a difficult observation. Aristarchus tried and got a result that the Sun was about 19 times the distance of the Moon. The Sun-Earth-Moon angle he got was 87°. Hipparchus measured the Moon to be 60 earth radii away which is near the Moon’s actual distance from the Earth. In actuality the Sun is about 400 times the distance to the Moon.
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
Ephemeris: 03/21/2024 – Three lunar craters named for heliocentrists by a geocentrist
This is Ephemeris for Thursday, March 21st. Today the Sun will be up for 12 hours and 14 minutes, setting at 7:57, and it will rise tomorrow at 7:41. The Moon, halfway from first quarter to full, will set at 6:59 tomorrow morning.
The gibbous moon tonight is exhibiting, over the last three days, three craters named for those who promoted the heliocentric or Sun centered solar system. The largest crater of the three, Copernicus, can be seen to the lower left of the center of the Moon. The asteroid that hit it made a big splash, which can be seen in its rays of ejecta being round and full. Then about halfway between it and the terminator is a small crater named for Johannes Kepler, and then nearby and on the terminator tonight is the crater named for the Greek philosopher who first proposed the Sun centered solar system, or in his case the universe, Aristarchus. He was a contemporary of and overshadowed by Aristotle, so his ideas were never adopted.
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
These craters were named by Giovanni Battista Riccioli, an astronomer and Jesuit priest. He established the lunar nomenclature we have today and named many of the largest craters. Being a 17th century Catholic, he bought the Roman Catholic line that the universe was geocentric, that is earth centered, yet he honored these heliocentrists with their own craters. He tended to group crater names by their relationship in life or their ideas, so the three proponents of the Sun centered solar system were given craters near each other in one section of the Moon.
Aristarchus of Samos was a Greek philosopher who lived between 310 and 230 BCE. He proposed a heliocentric solar system or universe, where Earth and all the planets revolved about the Sun. However, the work that he proposed it in has been lost. We know of his idea only referenced in the writings of others who attempted to debunk it.
Copernicus (Mikola Kopernik 1473-1543), was a Polish Catholic Canon, who was a mathematician, astronomer and translator, among other talents. He came up with the theory of the Sun centered or heliocentric solar system or in his day, universe.
Johannes Kepler (1571–1630) was an astronomer, astrologer and mathematician who discovered the laws of planetary motion. While Copernicus kept the circular orbits of the planets, they still didn’t match the motions of the planets in the sky. So he had to add some epicycles to make it all work. He actually had more epicycles than Ptolemy had. Kepler was able to figure out that he didn’t need epicycles if he assumed that the orbits were elliptical. He developed his Three Laws of Planetary Motion.
Galileo also has a crater there (Galilaei). It’s a tiny crater right on the terminator, below Kepler in the images above, and not visible. The Virtual Moon Atlas does not give an origin of the naming of the crater. Back in 1651, when Riccioli was giving craters names, Galileo was still on the outs with the Vatican, and the church.
Ephemeris: 02/19/2024 – A Kilonova may have exploded close to the Earth 3.5 million years ago
This is Ephemeris for President’s Day, Monday, February 19th. Today the Sun will be up for 10 hours and 38 minutes, setting at 6:16, and it will rise tomorrow at 7:36. The Moon, 3 days past first quarter, will set at 6:00 tomorrow morning.
One wouldn’t think that astronomy can be studied by taking samples of sediments from the ocean floor, but it can. One of the rare isotopes of iron is found there, iron 60, it is radioactive and has a half-life of about 2.5 million years. That means in 2.5 million years half of it would decay, and in another 2.5 million years half of the remaining half would decay, and so on. So its presence means it would have arrived relatively recently, compared to the four and a half billion year age of the Earth. One of the thoughts about its origin is that it came from a nearby kilonova, which is a collision of two neutron stars that occurred about 3.5 million years ago. A kilonova is brighter than a nova by about a thousand times, hence its name, but not as bright as a supernova.
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
And https://phys.org/news/2023-12-scientists-evidence-nearby-kilonova-million.html
Ephemeris: 12/22/2023 – Jupiter and Venus as the Star of Bethlehem
This is Ephemeris for Friday, December 22nd. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:05, and it will rise tomorrow at 8:17. The Moon, 3 days past first quarter, will set at 4:53 tomorrow morning.
Many writers of the 2nd and 3rd centuries AD place Jesus’ birth around 2 BC, which had to be before Herod the Great’s death, which I suggest was in 1 BC marked by a total lunar eclipse. So the Star of Bethlehem could appear several years later than the triple conjunction of Jupiter and Saturn in 7 BC that’s been popular. In 3 and again in 2 BC there were star-like conjunctions or apparent joining of the planets Jupiter and Venus against the backdrop of the constellation of Leo the Lion. A lion is related to Judah, son of Jacob by a blessing the latter gave his 12 sons in Genesis. The first conjunction occurred in August of 3 BC in the morning sky. On June 16th of the next year the two planets got together again, this time in the evening sky, a month or more after Jesus would have been born in the lambing season of spring.
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
Bob Moler's Ephemeris Blog 