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Ephemeris: 04/10/2025 – Saturn is soon going to emerge from the morning twilight
This is Ephemeris for Thursday, April 10th. Today the Sun will be up for 13 hours and 15 minutes, setting at 8:22, and it will rise tomorrow at 7:04. The Moon, 2 days before full, will set at 6:29 tomorrow morning.
The planets that have transitioned from the evening sky to the morning sky are beginning to show up in the morning now as they separate themselves from the Sun. Venus is the first to appear low in the east starting about 6:00 in the morning. Saturn will be very near Venus and below right of it on the 28th of this month. Saturn will separate itself more and more from the Sun over the spring and summer months until in late September when it becomes, officially, an evening planet again. Venus will increase its separation from the Sun until May 31st, its greatest separation from the sun of 46°. Then it will slowly head back towards the direction of the Sun. However, it will stay in the morning sky for the rest of the year.
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
On the 28th, both planets will be at the same distance west of the sun in right ascension, which is the same as longitude in the Earth’s coordinate system. The two planets were a bit closer on the 25th. Saturn is just a little bit less than three degrees above the horizon in the above image. One needs a low eastern horizon to spot it. Saturn may be visible a few days before that, however it is lacking a bright ring right now. The Earth passed through the Saturn’s ring plane on March 23rd, and we are now looking at, probably, a thin line through the planet. The ring should be fairly dim because the Sun is shining on the other side of the rings, and will until its crossover on May 6th.
Ephemeris: 04/09/2025 – Taking our weekly look at the whereabouts of the naked-eye planets
This is Ephemeris for Wednesday, April 9th. Today the Sun will be up for 13 hours and 12 minutes, setting at 8:20, and it will rise tomorrow at 7:06. The Moon, 3 days before full, will set at 6:13 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. Jupiter, now becomes the brightest evening planet, our substitute evening star if you will. It will be high in the west at 9 PM. Below it is the bright star Aldebaran. To its lower left, the great constellation of Orion. The rapidly fading Mars, with its distinctive reddish hue, is high in the south-southwest, in line with the stars Castor and Pollux in Gemini above right of it. By 6 AM Venus will be seen very low in the east, as the Morning Star,. It will require a low eastern horizon. It should be visible until about 6:45. Saturn should be visible in the morning by the end of the month.
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: 04/02/2025 – Let’s take our weekly look at the whereabouts of the naked-eye planets
This is Bob Moler with Ephemeris for Wednesday, April 2nd. Today the Sun will be up for 12 hours and 50 minutes, setting at 8:12, and it will rise tomorrow at 7:19. The Moon, 2 days before first quarter, will set at 2:19 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. 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 and above it tonight will be the crescent Moon. 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. Venus may become visible in a few days low in the east starting as early as 6:30 AM. It will require a low eastern horizon, since it will be very low in the sky.
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: 03/31/2025 – Finding Leo, the celestial lion
This is Ephemeris for Monday, March 31st. Today the Sun will be up for 12 hours and 44 minutes, setting at 8:09, and it will rise tomorrow at 7:23. The Moon, 2 days past new, will set at 11:39 this evening.
At 10 p.m. the spring constellation of Leo the lion will be high in the south-southeast. It can be found by locating the Big Dipper high in the northeast and imagining that a hole were drilled in the bowl to let the water leak out. It would drip on the back of this giant cat. The Lion is standing or lying facing westward. His head and mane are seen in the stars as a backwards question mark. This group of stars is also called the sickle. The bright star Regulus is at the bottom, the dot at the bottom of the question mark. A triangle of stars, to the left of Regulus, is the lion’s haunches. Leo contains some nice galaxies visible in moderate sized telescopes. The stars in Leo’s part of the sky are fewer than those in the winter sky.
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: 03/27/2025 – Cancer the celestial crab
This is Bob Moler with Ephemeris for Thursday, March 27th. Today the Sun will be up for 12 hours and 32 minutes, setting at 8:04, and it will rise tomorrow at 7:30. The Moon, 2 days before new, will rise at 7:08 tomorrow morning.
At 10 PM, between the stars Castor and Pollux in Gemini high in the southwest and the star Regulus in Leo the Lion in the southeast lies the dimmest constellation of the zodiac, Cancer the crab. To me its 5 brightest stars make an upside down Y. There are the stars in the center of the constellation Asellus Borealis and Asellus Australis, the north and south donkeys. There’s a fuzzy spot between and just west of them called Praesepe, the manger, from which they are eating hay. In binoculars, it resolves into a cluster of stars called the Beehive cluster. We amateur astronomers also know it as M44, the 44th object on 18th century comet hunter Charles Messier’s list of fuzzy objects that might be mistaken for comets.
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: 03/26/2025 – 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: 03/19/2025 – 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: 03/13/2025 – 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 