Archive
Ephemeris: 04/01/2026 – No fooling, we’re looking at the bright planets for this week
This is Ephemeris for April Fools’ Day, Wednesday, April 1st. Today the Sun will be up for 12 hours and 47 minutes, setting at 8:10, and it will rise tomorrow at 7:21. The Moon, at full today, will rise at 8:06 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. By 8:40 PM tonight or about a half hour or so after sunset, Venus may be seen very low in the West. Binoculars or a telescope will show a very tiny disc on Venus, because it is pretty much behind the Sun, a good way from us. Over the next 7 months it will be moving closer to us and becoming much larger. Jupiter is the brilliant star-like object more than halfway up in the southwestern sky at 9 PM. At that time Venus will still be visible, setting at 9:57 PM. Mercury, Mars and Saturn are lined up just west of the Sun, but unfortunately are overwhelmed by bright morning twilight.
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: 03/25/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, March 25th. Today the Sun will be up for 12 hours and 25 minutes, setting at 8:01, and it will rise tomorrow at 7:34. The Moon, at first quarter today, will set at 4:26 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Earlier this morning Saturn passed conjunction with the Sun becoming officially a morning planet. But it’ll be a couple of months before it’s visible in the morning and about seven months before it’s conveniently placed in the evening sky. By 8:30 PM tonight or about a half hour or so after sunset, Venus may be seen very low in the West. Binoculars or a telescope will show a very tiny disc on Venus, because it is pretty much behind the Sun, a good way from us. Over the next 7 months it will be moving closer to us and becoming much larger. Jupiter is the brilliant star-like object more than halfway up in the southwestern sky at 9 PM. Tonight, it’s below and left of the Moon.
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: 03/18/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, March 18th. Today the Sun will be up for 12 hours and 3 minutes, setting at 7:52, and it will rise tomorrow at 7:47. The Moon is new today, and won’t be visible.
Let’s take our weekly look at the whereabouts of the naked-eye planets. By 8:30 PM or about a half hour or so after sunset, Venus may be seen very low in the West. Binoculars or a telescope will show a very tiny disc on Venus, because it is pretty much behind the Sun, a good way from us. However over the next 7 months it will be moving closer to us and becoming much larger. Jupiter is the brilliant star-like object more than halfway up in the southern sky at 9 PM. It’s the brightest object in the sky at that point. It has resumed its normal eastward motion, spending most of its evening appearance making up the ground it lost in its 4 months of retrograde motion. The planet and its moons are a treat for binoculars or a telescope.
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.
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Ephemeris: 03/11/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, March 11th. Today the Sun will be up for 11 hours and 41 minutes, setting at 7:43, and it will rise tomorrow at 8:00. The Moon, at last quarter today, will rise at 4:42 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 8:15 PM or about a half hour after sunset, Venus may be seen very low in the West. A very low western horizon will be necessary to spot it, like from the shore of Lake Michigan. Saturn is no longer visible, being too close to the direction of the Sun. Jupiter is the brilliant star-like object more than halfway up in the southern sky. It’s the brightest star-like object in the sky. The planet and its moons are a treat for binoculars or a telescope. Jupiter’s four brightest, so-called Galilean Moons are on the east side of the planet, though binoculars will probably show three. The moon closest to the planet are two moons close together, which are resolved in telescopes.
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: 03/04/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, March 4th. Today the Sun will be up for 11 hours and 19 minutes, setting at 6:34, and it will rise tomorrow at 7:13. The Moon, 1 day past full, will rise at 8:14 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 7 PM or about a half hour after sunset, Venus may be seen very low in the West. Above it and a bit to the left might be Saturn which may not show up until a quarter of an hour later. We are in the last third of winter and the sunset times are increasing rapidly and taking with it Saturn. The evening sky will shift dramatically this Sunday when Daylight Saving Time returns, giving us darker mornings and brighter evenings. Jupiter is the brilliant star-like object more than halfway up in the southern sky. It’s the brightest star-like object in the sky. The planet and its moons are a treat for binoculars or a telescope.
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: 02/25/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, February 25th. Today the Sun will be up for 10 hours and 58 minutes, setting at 6:25, and it will rise tomorrow at 7:25. The Moon, 1 day past first quarter, will set at 4:37 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 7:00 PM or about and 1/2 hour after sunset Venus may be seen very low in the West above it and a bit to the right is Mercury which will be really difficult to spot since it is dimming now and above left of that is Saturn which is getting very low in the sky. We are in the last third of winter and the sunset times are increasing rapidly and taking with it the planets near the Sun including Saturn. By 8 PM Saturn will be very low in the West and not a very good object for telescope viewing. Jupiter is the brilliant star-like object more than halfway up in the southeastern sky, and tonight is below and left of the Moon. It’s the brightest star-like object in the sky. It is still moving to the west, but is slowing down and will stop and reverse its course 13 days from now.
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: 02/18/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Ash Wednesday, February 18th. Today the Sun will be up for 10 hours and 37 minutes, setting at 6:15, and it will rise tomorrow at 7:36. The Moon, 1 day past new, will set at 7:52 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. After sunset Venus may show up very low in the West probably before 7:00 PM. Above Venus, tonight, will be the 1 1/2 day old Moon and above it and very close, the planet Mercury making a rare appearance in our evening sky. At 8 PM Saturn remains low in the west southwestern sky, and it will set before 9 PM. In a telescope Saturn sports a very thin ring, 3.1 degrees from being edge on and is slowly opening. Jupiter is the brilliant star-like object more than halfway up in the east-southeastern sky. It’s the brightest star-like object in the sky. It is still moving to the west, but is slowing down and will stop and reverse its course 20 days now.
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.
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Ephemeris: 02/13/2026 – The real cause of a planet’s retrograde motion
This is Ephemeris for Friday, February 13th. Today the Sun will be up for 10 hours and 22 minutes, setting at 6:08, and it will rise tomorrow at 7:44. The Moon, halfway from last quarter to new, will rise at 6:30 tomorrow morning.
So what is the real reason that Jupiter is currently moving westward for a while in retrograde motion? Retrograde motion occurs in outer planets because the Earth is actually passing them. A simple analogy would be, if you were in a car that was passing another, the car you are passing would seem to move backwards compared to you. And that is exactly what’s happening. The Earth moves faster than the outer planets. Since the solar system is like a racetrack, and we get to lap these outer planets repeatedly when they are closest to us. For the inner planet it’s opposite. They go retrograde or backwards when they are passing us. This is a much simpler answer than all these circles upon circles the ancients invented.
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: 02/12/2026 – Why do planets stop and move backward for a time? Part 1
This is Ephemeris for Darwin Day, Thursday, February 12th. Today the Sun will be up for 10 hours and 19 minutes, setting at 6:07, and it will rise tomorrow at 7:45. The Moon, 3 days past last quarter, will rise at 5:49 tomorrow morning.
For the last month or so I’ve been talking about Jupiter in its retrograde or westward motion against the stars of Gemini. This motion isn’t due to just Jupiter itself. Jupiter orbits smoothly around the sun in one direction, in a little less than 12 years. The ancients thought that the earth was stationary, and everything in the sky orbited the earth. They thought that the planets orbited the earth in the same time that the planet orbits the sun, however every year and depending on where the planet was in the sky it would stop, reverse itself for a while and then resume its eastward motion through the sky. They thought that the planet moved on a small circle called an epicycle that rode on the larger circle called the deferent.
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

Tomorrow, we’ll find out what’s really going on.
Ephemeris: 02/11/2026 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, February 11th. Today the Sun will be up for 10 hours and 16 minutes, setting at 6:05, and it will rise tomorrow at 7:47. The Moon, 2 days past last quarter, will rise at 5:00 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Before twilight fades, Mercury may be spotted low in the west below and right of Saturn. Binoculars may help in finding it. Saturn is the brightest star-like object low in the west southwestern sky as soon as it gets dark, and it will set before 9:30. In a telescope Saturn sports a very thin ring, 2.6 degrees from being edge on and is slowly opening. Jupiter is the brilliant star-like object more than halfway up in the east-southeastern sky. It’s the brightest star-like object in the sky. It is still moving to the west, but is slowing down and will stop and reverse its course a month from now. Jupiter’s 4 brightest moons can be seen even in binoculars, if held steadily enough. They shift position night to night. At 8 PM tonight, all four Galilean moons can be seen.
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


Tomorrow, I’ll discuss, more fully, why planets are seen to move in retrograde motion.


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