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Ephemeris: 03/26/2025 – Where have all the naked-eye planets wandered off to?
This is Bob Moler with Ephemeris for Wednesday, March 26th. Today the Sun will be up for 12 hours and 29 minutes, setting at 8:03, and it will rise tomorrow at 7:32. The Moon, 3 days before new, will rise at 6:47 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 9 PM this evening just two of the five naked eye planets will be out. Venus and Mercury have gone over to the dark… uh, morning side proceeded by Saturn, a month ago. Jupiter now becomes the brightest evening planet, our substitute evening star if you will. It will be high in the west-southwest at 9 PM. Below it is the bright star Aldebaran with the stars of the Hyades, the face of Taurus the bull, and farther to the right the star group the Pleiades or Seven Sisters. To its lower left, the great constellation of Orion. The rapidly fading Mars, with its distinctive reddish hue, is high in the south, with the stars Castor and Pollux in Gemini above it.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 03/25/2025 – Spotting Zodiacal light
This is Ephemeris for Tuesday, March 25th. Today the Sun will be up for 12 hours and 26 minutes, setting at 8:02, and it will rise tomorrow at 7:34. The Moon, 3 days past last quarter, will rise at 6:24 tomorrow morning.
The evening sky will stay dark for the rest of the week, so it’s time to look for the zodiacal light in the evening. It is a faint but towering glow that can be seen after the end of astronomical twilight on moonless nights. It is seen in the west in the evening in late winter and early spring. The axis of the glow is the ecliptic, the apparent annual path of the Sun in the sky, along which lie the constellations of the zodiac. It’s a glow whose wide base is in the west that extends upwards and to the left. Right now, the end of astronomical twilight is about 10:05 p.m. and advancing at a rate of a minute or two each night. Go to a spot with a dark western sky, no big cities or towns out that way. Zodiacal light is caused by dust spread out around the Sun.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Zodiacal light will not be as obvious as it appears in the above photographs, where I got to play with brightness and contrast. It takes a bit of observation back and forth to spot the glow. Once found it will be easier to spot in future attempts. Zodiacal light can also be seen on fall mornings in the east before twilight begins. The glow will lean to the right instead of to the left.
Ephemeris: 03/24/2025 – Mercury crosses over to the morning side
This is Ephemeris for Monday, March 24th. Today the Sun will be up for 12 hours and 22 minutes, setting at 8:00, and it will rise tomorrow at 7:36. The Moon, 2 days past last quarter, will rise at 5:58 tomorrow morning.
Today, Mercury is at inferior conjunction with the Sun, two days after Venus. Mercury of course, this is in the middle of its retrograde motion period, moving westward against the stars, and for astrologers Mercury in retrograde is a big deal. I consider astrology is to astronomy as tea-leaf reading is to botany, so I dismiss it. Every once in a while Mercury, when it passes inferior conjunction, crosses in front of the face of the Sun for us. These are called transits, and are fairly rare. The last time was in November 2019 and the next time will be in November 2032 which is seven years from now. Mercury will move into the morning sky, where its appearance will not be favorable for us in the Northern Hemisphere.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Retrograde loops are caused by looking at a moving planet from another moving planet, the Earth.
Ephemeris: 03/21/2025 – Venus will pass inferior conjunction with the Sun tomorrow
This is Ephemeris for Friday, March 21st. Today the Sun will be up for 12 hours and 13 minutes, setting at 7:56, and it will rise tomorrow at 7:41. The Moon, 1 day before last quarter, will rise at 3:55 tomorrow morning.
Tomorrow Venus will be in inferior conjunction with the Sun. That means that Venus will be moving between the Earth and the Sun, on its way from the evening sky to the morning sky. Venus’ orbit has an inclination to the Earth’s orbit of 3.4° and when we are closest to Venus as we are now only 26 million miles (42 million kilometers) away, that inclination gets exaggerated so that Venus is almost nine degrees north of the Sun. Venus gets about 8 million miles (13 million kilometers) closer to us than Mars ever gets. Of course when Mars gets that close it is fully illuminated. When Venus is at its closest we’re looking at its night side and couldn’t see anything even if we didn’t have the glare of the Sun.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 03/20/2025 – Spring has sprung!
This is Ephemeris for Thursday, March 20th. Today the Sun will be up for 12 hours and 10 minutes, setting at 7:55, and it will rise tomorrow at 7:43. The Moon, 2 days before last quarter, will rise at 2:57 tomorrow morning.
At 5:02 AM this morning the Sun passed overhead on the Earth’s equator heading northward beginning the season of spring. It is called the vernal or spring equinox also the March equinox if you didn’t care which hemisphere you lived in. Anyway, our daylight hours become longer and longer until June 21st the first day of summer. We have been seeing the effects of all this because all winter long the daylight hours have been getting longer and now in the last few weeks our temperatures have begun to rise, especially last Friday and Saturday. Along with the increased daylight hours the Sun is also getting higher in the sky giving us a more concentrated heating, it’s light and heat not being spread out as much as it was during the winter.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 03/19/2025 – Suddenly there are only two planets visible in the evening
This is Ephemeris for Wednesday, March 19th. Today the Sun will be up for 12 hours and 7 minutes, setting at 7:54, and it will rise tomorrow at 7:45. The Moon, 3 days before last quarter, will rise at 1:53 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. At 9 PM this evening just two of the five naked eye planets will be out. Venus and Mercury are too close to the Sun in the twilight to be seen. Saturday and Monday Venus and then Mercury will pass between the Earth and the Sun to enter the morning sky. Jupiter, now becomes the brightest evening planet. It will be high in the southwest. Below it is the bright star Aldebaran with the stars of the Hyades, the face of Taurus the bull, and to the lower left, the great constellation of Orion, The rapidly fading Mars, with its distinctive reddish hue, is high in the south, with the stars Castor and Pollux in Gemini above it.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 03/18/2025 – The Great Underwater Panther
This is Ephemeris for Tuesday, March 18th. Today the Sun will be up for 12 hours and 4 minutes, setting at 7:53, and it will rise tomorrow at 7:47. The Moon, halfway from full to last quarter, will rise at 12:47 tomorrow morning.
As Orion tilts into the southwest at 9 PM I’m reminded of our Anishinaabek native peoples here in Michigan who saw it as the Winter Maker slowly beginning to leave the scene in the southwest. At this time in the southeast is Curly Tail, the Great Panther. I first knew him as the Great Underwater Panther, which tells us where he lives… beneath the ice. He’s in the sky to warn us that the warmer weather of spring is coming, and the ice on the lakes and rivers is getting thin. Be careful to not fall through and drown, becoming a victim of the Great Panther. The stars of the panther include those of the head of Leo the lion the great backwards question mark, as his curly tail, to his head, the head of what we call Hydra the water snake.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 03/17/2025 – When the largest telescope in the world was in Ireland
This is Ephemeris for St. Patrick’s Day, Monday, March 17th. Today the Sun will be up for 12 hours and 1 minute, setting at 7:51, and it will rise tomorrow at 7:49. The Moon, 3 days past full, will rise at 11:40 this evening.
In the 19th century Ireland laid claim to having the largest telescope in the world. It was a reflecting telescope with a mirror diameter of 72 inches. It was built by William Parsons the Third Earl of Rosse. The base of the telescope tube rested in a pit between two massive walls and could only look to either side of a north-south direction. It saw first usage in 1847. The telescope was called the Leviathan of Parsonstown, and was in use until 1890. Mirrors in those days were made of a silvery alloy called speculum. Two mirrors were used alternately because speculum tarnished. The mirror not in use would have to be re-polished and swapped in from time to time. It was the largest telescope until the 100 inch at Mt. Wilson was put in service in 1917.
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: 03/14/2025 – Viewing today’s eclipse from the Moon
This is Ephemeris for Pi Day, Friday, March 14th. Today the Sun will be up for 11 hours and 51 minutes, setting at 7:48, and it will rise tomorrow at 7:54. The Moon, at full today, will rise at 8:27 this evening.
I hope you had a good look at the eclipse this morning I don’t know if it was clear or cloudy because I’m recording this last Sunday night. One entity got a cloudless shot at seeing the eclipse without any obstructions. That was the Blue Ghost lander on Mare Crisium on the Moon. However, it was on the Moon so it was seeing a total eclipse of the Sun. I’ll be really interested to see the photographs coming back from that. There was a satellite and one lander, the Surveyor 3 Lander on the Moon that took pictures of the Earth during the solar eclipse. Of course, we saw a lunar eclipse. It just saw a ring of light around the Earth where the Sun’s light was being bent through the Earth’s atmosphere into it’s shadow to dully illuminate the Moon.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Sorry, I couldn’t spend any time on the program to celebrate Pi day, so I’ll give it a token appreciation here:
Update
Firefly Aerospace.
Ephemeris: 03/13/2025 – Get ready for tomorrow morning’s total lunar eclipse
This is Ephemeris for Thursday, March 13th. Today the Sun will be up for 11 hours and 48 minutes, setting at 7:46, and it will rise tomorrow at 7:56. The Moon, 1 day before full, will set at 8:06 tomorrow morning.
Late, late, late, tonight, or actually early tomorrow morning there will be a total eclipse of the Moon. The moment of full moon, which is necessary for a lunar eclipse will occur at 2:55 AM tomorrow, and the middle of the eclipse will be 5 minutes later. The partial phase of the lunar eclipse will start at 1:10 AM. This partial phase will grow until 2:26 AM when totality will begin. During this period of time the Moon should have a dull reddish color because it is illuminated only by the light filtering through the Earth’s atmosphere from the combined sunrises and sunsets around the world at that time. The total phase will end at 3:31 AM. The ending partial phase will continue until 4:48 AM.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Bob Moler's Ephemeris Blog 