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Ephemeris: 01/29/2025 – Our weekly look at the whereabouts of the naked-eye planets
This is Bob Moler with Ephemeris for Wednesday, January 29th. Today the Sun will be up for 9 hours and 42 minutes, setting at 5:47, and it will rise tomorrow at 8:03. The Moon is new today, and won’t be visible.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 8 PM this evening four of the five naked eye planets will be out. Starting from the West we have Venus the brightest of all low in the west southwest. Almost directly below it will be the much dimmer Saturn. Jupiter, the second-brightest planet will be high in the south-southeast. Below it is the letter V shape of stars that is the head of Taurus the bull. Farther below is the spectacular constellation of Orion the hunter. The 4th planet out is Mars, the third-brightest planet now, with its distinctive reddish hue, near the star Pollux in Gemini, and just about due east. The fifth naked eye planet, Mercury, is too close to the Sun in the morning to be visible.
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: 01/22/2025 – Let’s take our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, January 22nd. Today the Sun will be up for 9 hours and 26 minutes, setting at 5:38, and it will rise tomorrow at 8:10. The Moon, 1 day past last quarter, will rise at 3:07 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 8 PM this evening four of the five naked eye planets will be out. Starting from the West we have Venus the brightest of all low in the west southwest. Directly below it will be the much dimmer Saturn. Jupiter, the second-brightest planet will be high in the southeast. Below and right of it is the letter V shape of stars that is the head of Taurus the bull. Farther below is the spectacular constellation of Orion the hunter. The 4th planet out is Mars, the third brightest planet now, with its distinctive reddish hue, near the star Pollux in Gemini. The fifth naked eye planet, Mercury, is too close to the Sun in the morning to be visible.
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: 01/17/2025 – Venus passes Saturn in conjunction tomorrow
We end this week of planetary events with this post:
This is Ephemeris for Friday, January 17th. Today the Sun will be up for 9 hours and 16 minutes, setting at 5:31, and it will rise tomorrow at 8:14. The Moon, halfway from full to last quarter, will rise at 9:44 this evening.
Venus will pass the slower moving Saturn at about 11:00 tomorrow morning, so tonight and Saturday night are your best times to see these two planets at their closest. They will probably be slightly closer tomorrow night than tonight. This apparent meeting of two planets is called a conjunction. The two planets are not anywhere close to each other, in fact Venus is closer than the Sun right now, and Saturn is 10 times farther away than the Sun. They just happen to be near the same line of sight. From there both will lose their battle with evening twilight. Saturn will make it back to conjunction with the Sun first, ten days before Venus. Before that Mercury will pass in conjunction with Venus.
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: 01/15/2025 – Our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, 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, 2 days past full, will rise at 7:27 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 8 PM this evening four of the five naked eye planets will be out. Starting from the West we have Venus the brightest of all low in the west southwest. Left and a bit above it is Saturn. They will appear at their closest Friday and Saturday nights. Jupiter, the second-brightest planet will be high in the southeast. The 4th planet out is Mars, which is at opposition from the Sun tonight. Mars will not get this close to the Earth again until 2031. It shines with its reddish hue a third as bright as Jupiter in the eastern sky. On unusually close approaches, Mars can actually outshine Jupiter. The fifth naked eye planet, Mercury, is too close to the Sun on the morning side to be visible.
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
Translations of some lunar feature names according to Virtual Moon Atlas
Mare Cognitum – Sea of Knowledge
Mare Crisium – Sea of Crises
Mare Fecunditatis – Sea of Fruitfulness
Mare Frigoris – Sea of Cold
Mare Humorum – Sea of Moisture
Mare Imbrium – Sea of Showers
Mare Nectaris – Sea of Nectar
Mare Nubium – Sea of Clouds
Mare Serenitatis – Sea of Serenity
Mare Tranquillitatis – Sea of Tranquility
Mare Vaporum – Sea of Vapors
Montes Alpes – Alps Mountains
Montes Apenninus – Apennines Mountains
Oceanus Procellarum – Ocean of Storms
Sinus Iridium – Bay of Rainbows
Sinus Medii – Central Bay
Mare is pronounced Mar-e. Craters are named for persons, real or otherwise.
Ephemeris: 01/10/2025 – Venus’ split personality
This is Ephemeris for Friday, January 10th. Today the Sun will be up for 9 hours and 4 minutes, setting at 5:22, and it will rise tomorrow at 8:18. The Moon, 3 days before full, will set at 6:40 tomorrow morning.
In very ancient times the Greeks thought that Venus in the evening as we see it now and Venus in the morning sky were two separate planets. The evening appearance was Aphrodite the goddess of love, and in the morning sky it was Phosphorus, the bringer of light, that being dawn. In Roman times Aphrodite became Venus and Phosphorus became Lucifer. It is interesting that Venus and Aphrodite are female while Phosphorus and Lucifer are male. Another term for Venus which I even use colloquially, is Evening Star for its current location and Morning Star in the morning sky, even though it’s a planet not a star. Venus is a beautiful planet in our sky, but a hellish planet in reality. No wonder Elon Musk would rather go to Mars than the much closer Venus.
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: 01/09/2025 – Venus is at its greatest separation from the Sun today
This is Ephemeris for Thursday, 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, 3 days past first quarter, will set at 5:25 tomorrow morning.
Tonight, Venus will be at its greatest separation from the Sun in the sky at a little bit more than a 47° angle. Venus, being inside the Earth’s orbit, can ever stray far from the Sun. So today it is at its greatest eastern elongation from the Sun. For the rest of winter it will be moving closer to the Sun from our perspective. Crossing between the Earth and the Sun on March 22nd. During this period of time Venus will be a great object for the telescope, as it moves closer to the Earth and gets larger in telescopes and its phase, moving from being like a quarter moon to a very thin crescent near the end of winter. At inferior conjunction with the Sun, Venus will be only 26 million miles away from us, but quite invisible in the Sun’s glare.
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
The Mayan civilization of Central America had several calendars. One of them was based on the planet Venus. They discovered that Venus repeated its positions in the sky with respect with the seasonal calendar over a period of eight years, which they called a Venus Sequence. They paid close attention to Venus and discovered it appeared to go around the Sun in the sky in 584 days, which they called a Venus Cycle. We call it Venus’ synodic period, which is the number of days between inferior conjunction, when Venus passes between the Earth and the Sun, then moves through the morning sky, and disappears behind the Sun at superior conjunction, then appears in the evening sky and back to inferior conjunction again. The gray area in the diagram is where Venus is not visible because it’s too close to the sun. However, at our latitude the number of days that Venus is invisible varies with the season. The Mayans, being in the tropics, didn’t have as much variation as we do. The Mayans discovered that Venus completed 5 cycles in almost exactly 8 years.
Today, Venus is at its greatest eastern elongation. On March 22nd Venus will pass inferior conjunction. That is 72 days from today. So it spends most of its time, 7 months, moving from around behind the Sun to the greatest elongation and only a short time, about 2 1/2 months moving from there to inferior conjunction. These 2 1/2 months are the best time to view Venus with a telescope, since Venus will grow in size and become an ever thinning crescent.
Check out my Wednesday posts showing the ever-growing and thinning Venus crescent until March 22nd. Or better yet, see it for yourself with a small telescope.
Ephemeris: 01/08/2025 – A weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, January 8th. Today the Sun will be up for 9 hours and 1 minute, setting at 5:20, and it will rise tomorrow at 8:18. The Moon, 2 days past first quarter, will set at 4:05 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 8:00 PM this evening four of the five naked eye planets will be out. Starting from the West we have Venus the brightest of all low in the west southwest. Above and left of that is Saturn. The waxing gibbous moon is high in the South at that time. Jupiter, the second-brightest planet will be high in the southeast. The 4th planet out is Mars which is low in the east northeast with its reddish hue giving it away. Next Monday the Moon will pass directly over the planet Mars in our evening sky. The fifth naked eye planet, Mercury, is too close to the Sun on it morning side to be visible.
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: 01/01/2025 – A New Year’s Day look at the naked-eye planets
This is Ephemeris for New Year’s Day, Wednesday, January 1st, 2025. The Sun will rise at 8:20. It’ll be up for 8 hours and 53 minutes, setting at 5:13. The Moon, 2 days past new, will set at 7:02 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus can be spotted in the south-southwestern sky by 5:45 PM, about 30 minutes after sunset, and will also be above and left of the thin crescent Moon. Venus will set at 9:10 PM. Saturn will be in the south-southwestern sky at 6 PM, above and left of Venus, which will be seen to cross paths with it on the 18th of this month. Jupiter is low in the east, about the same time Venus is first spotted. It will be a good object for the small telescope. Mars, rises tonight at 6:31. Mars is still considered a morning planet since it is still up at sunrise. But that will end on the 15th of this month, when Mars reaches opposition from the Sun.
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.
Happy New Year! I do really hope it will be happy…
Addendum
Ephemeris: 12/25/2024 – A Christmas week look at the naked-eye planets
This is Ephemeris for Christmas Day, Wednesday, December 25th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:07, and it will rise tomorrow at 8:19. The Moon, 3 days past last quarter, will rise at 4:16 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus can be spotted in the south-southwestern sky by 5:30 PM, about 30 minutes after sunset. It will set at 8:41 PM. Saturn will be in the south at 6 PM, way above the bright star Fomalhaut. Jupiter is low in the east-northeast, about the same time Venus is first spotted. It will be a good object for the small telescope about an hour later. Mars, rises tonight at 7:44, It will appear above the Moon in the evening. Mars is still considered a morning planet since it is still up at sunrise. By 6:00 AM tomorrow Jupiter will be low in the west-northwest, to the right of the setting Orion, while reddish Mars will be high in the west-southwest.
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.
Bob Moler's Ephemeris Blog 