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Ephemeris: 02/05/2025 – Let’s take our weekly look at the naked-eye planets
This is Ephemeris for Wednesday, February 5th. Today the Sun will be up for 10 hours and 1 minute, setting at 5:57, and it will rise tomorrow at 7:55. The Moon, at first quarter today, will set at 3:14 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 7:30 PM this evening four of the five naked eye planets will be out. Starting from the West we have Venus the brightest of all in the west southwest. Far below it, near the horizon, will be the much dimmer Saturn. Jupiter, the second-brightest planet will be high in the south-southeast. It is reversing course and beginning to head back eastward now. Farther below it 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 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: 01/29/2025 – 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: 01/20/2025 – The planets augment the Winter Hexagon
This is Ephemeris for Martin Luther King Jr. Day, Monday, January 20th. Today the Sun will be up for 9 hours and 22 minutes, setting at 5:35, and it will rise tomorrow at 8:12. The Moon, 1 day before last quarter, will rise at 12:56 tomorrow morning.
The winter circle or more properly hexagon, seen in the winter sky this evening, has the addition of two planets, and they’re in the proper location so that they don’t spoil the hexagon. We start at the top with the star Capella high in the east. We move clockwise downward to Jupiter and below it the star Aldebaran. We drop lower to Orion’s knee and the star Rigel, then down to Sirius, low in the southeast, the brightest nighttime star, but doesn’t hold a candle to Jupiter. Then we go above left to Procyon and upwards and left to Mars, which is near Pollux, and finally back up to Capella. That’s that is our winter hexagon right now, so take it in while you can, before Jupiter and Mars move off and mess it up.
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
As for events happening on Earth: Resist!
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: 01/06/2025 – Things that go blink in the night
This is Ephemeris for Monday, January 6th. Today the Sun will be up for 8 hours and 58 minutes, setting at 5:18, and it will rise tomorrow at 8:19. The Moon, at first quarter today, will set at 1:26 tomorrow morning.
Lately there’s been a lot of reported observations of drones or various things in the sky at night, especially, for some reason, in New Jersey. If it’s something that’s moving in the sky other than satellites, meteors and aurorae, they’re out of my wheelhouse. I generally concern myself with the sidereal universe, the universe beyond the atmosphere. Things that don’t seem to move that rapidly. There are a lot of bright lights in the sky, that are things that I can and do talk about this time of year and this particular year. We have a lot of bright lights in the sky now, foremost Venus in the southwest in the early evening, and Jupiter in the east and the south. Mars is also up, but it’s not in competition with Jupiter this year. These plus the bright winter stars.
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
Bob Moler's Ephemeris Blog 