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Ephemeris: 09/30/2026 – Taking our weekly look at the whereabouts of the naked-eye planets

September 30, 2026 Leave a comment

This is Ephemeris for Wednesday, September 30th. Today the Sun will be up for 11 hours and 45 minutes, setting at 7:25, and it will rise tomorrow at 7:40. The Moon, 3 days before last quarter, will rise at 9:14 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus, now is too close to the horizon at sunset to easily spot. At sunset Venus will be only 4º above the horizon at sunset and will set at 7:52 PM. We will await its dramatic reappearance in the morning sky by early November. Saturn will be in the eastern sky as it gets dark. It is the brightest starlike object low in that direction. It will be below the four stars that make large distinctive pattern, that marks the body of Pegasus the flying horse, called the Great Square. At 6 AM, Jupiter and Mars will in the east. Jupiter is brightest and while red Mars will be above and just below and nearly in line with Castor and Pollux of Gemini.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Saturn appears in the east southeast by 10 PM, to the far right of the Moon tonight.
Saturn appears in the east southeast by 10 PM, to the far right of the Moon tonight, September 30, 2026. Created using Stellarium.
The Moon three days before full at 10 PM tonight, September 30, 2026. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Mars and Jupiter appear with the moon and the stars of winter, which now adorn the predawn sky at 6 AM.
Mars and Jupiter appear with the moon and the stars of winter, which now adorn the predawn sky at 6 AM. Created using Stellarium.
Telescopic views of the naked-eye planets as seen in a small telescope.
Telescopic views of the naked-eye planets as seen in a small telescope: At 9 PM, Saturn will be 19.7″ in diameter, and its rings extend to 45.9″. At 6 AM, Jupiter will be 33.3″ in diameter. Mars, not shown, will appear 5.6″ in diameter. The (”) symbol means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts), LibreOffice Draw and GIMP.
The naked-eye planets at sunset and sunrise on a single night, starting with sunset on the right on September 30, 2026. The night ends on the left with sunrise on October 1st.
The naked-eye planets at sunset and sunrise on a single night, starting with sunset on the right on September 30, 2026. The night ends on the left with sunrise on October 1st. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
The naked-eye planets, from Mercury to Saturn, in a low angle perspective view of the solar system from above and a bit beyond Saturn’s orbit for today, September 30, 2026.
The naked-eye planets, from Mercury to Saturn, in a low angle perspective view of the solar system from above and a bit beyond Saturn’s orbit for today, September 30, 2026. Created using my LookingUp app, text and arrows created using LibreOffice Draw and produced a unified image using GIMP.

Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

Ephemeris: Finding Andromeda and the great galaxy within

September 29, 2026 Leave a comment

This is Ephemeris for Tuesday, September 29th. Today the Sun will be up for 11 hours and 48 minutes, setting at 7:26, and it will rise tomorrow at 7:39. The Moon, 3 days past full, will rise at 8:35 this evening.

For at least the last thousand or so years a fuzzy spot in the constellation of Andromeda has been known. It was known as the Great Andromeda Nebula until a little over 100 years ago. Nebula means cloud, and it belonged to the Milky Way. At that time it was finally recognized as another Milky Way just like ours. So the word to call it was galaxy, a word that’s related to milk. It looks to be among the stars of Andromeda, but it’s far beyond the stars that we make the constellation of Andromeda. Current estimates place it at about two and a half million light years away, well beyond the stars that we see in Andromeda that range to only a few thousand light years distance. It could collide with our galaxy in about 4 billion years or so.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Andromeda finder animation looking east tonight.
Andromeda finder animation looking east tonight. The left corner star of the Great Square of Pegasus is called Alpheratz, and actually belongs to Andromeda. The faint fuzzy spot labeled Great Andromeda Galaxy, also known to astronomers as M31, is the Milky Way’s large neighbor. This image does not show the planet Saturn, which is below the Great Square this year. Created using Stellarium and GIMP.

Categories: Constellations, Ephemeris Program, Observing Tags: , ,

Ephemeris: 09/23/2026 – Where did Venus go?

September 23, 2026 Comments off

This is Ephemeris for Wednesday, September 23rd. Today the Sun will be up for 12 hours and 6 minutes, setting at 7:38, and it will rise tomorrow at 7:32. The Moon, 3 days before full, will set at 5:08 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus, now is too close to the horizon at sunset to easily spot. At sunset Venus will be only 5º above the horizon at sunset and will set at 8:25 PM. We will await its dramatic reappearance in the morning sky in early November. Saturn will be in the eastern sky as it gets dark. It is the brightest starlike object low in that direction. It will be below the four stars that make large distinctive pattern, that marks the body of Pegasus the flying horse, called the Great Square of Pegasus. At 6 AM, Jupiter will be due east. Jupiter is brightest and lowest while Mars will be just below and nearly in line with Castor and Pollux of Gemini.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Saturn appers in the east by 9 PM, to the far left of the Moon tonight, September 23, 2026.
Saturn appers in the east by 9 PM, to the far left of the Moon tonight, September 23, 2026. Created using Stellarium.
The Moon three days before full at 9 PM tonight, September 23, 2026. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Mars and Jupiter appear with the stars of winter, which now adorn the predawn sky at 6 AM.
Mars and Jupiter appear with the stars of winter, which now adorn the predawn sky at 6 AM. Created using Stellarium.
Telescopic views of the naked-eye planets as seen in a small telescope.
Telescopic views of the naked-eye planets as seen in a small telescope: At 9 PM, Saturn will be 19.7″ in diameter, and its rings extend to 45.8″. At 6 AM, Jupiter will be 32.9″ in diameter. Mars, not shown, will appear 5.5″ in diameter. The (”) symbol means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts), LibreOffice Draw and GIMP.
The naked-eye planets at sunset and sunrise on a single night.
The naked-eye planets at sunset and sunrise on a single night, starting with sunset on the right on September 23, 2026. The night ends on the left with sunrise on the 24th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
The naked-eye planets, from Mercury to Saturn, in a low angle perspective view of the solar system.
The naked-eye planets, from Mercury to Saturn, in a low angle perspective view of the solar system from above and a bit beyond Saturn’s orbit for today, September 23, 2026. Created using my LookingUp app, text and arrows created using LibreOffice Draw and produced a unified image using GIMP.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

Ephemeris: 09/18/2026 – The Moon will be lower than the winter solstice Sun tonight

September 18, 2026 Comments off

This is Ephemeris for Friday, September 18th. Today the Sun will be up for 12 hours and 22 minutes, setting at 7:47, and it will rise tomorrow at 7:26. The Moon, at first quarter today, will set at 11:40 this evening.

Tonight’s first quarter moon will appear low in the southern sky at its highest at about 11 minutes before sunset tonight. The moon is in the part of the sky where the sun will be on the first day of winter, December 21st at it’s lowest and the moon will be even lower tonight. For us, in Northern Michigan that’s 15 degrees, or one and a half times the width of a fist held at arms length. The moon, though, is even lower than the sun will be that day. The sun will be 22º above the southern horizon that day, a bit more than two fist widths above the southern horizon. I talk a lot about angles on this program, because measuring angles is what astronomers did before the invention of the telescope. A telescope allows better precision, among other attributes.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

The height of the moon tonight, September 18, 2026 at 7:39 PM forr the Interochen, Traverse City area to scale, and looking south. This is compared to the Sun on the winter solstice, December 21st.
The height of the moon tonight, September 18, 2026 at 7:39 PM forr the Interochen, Traverse City area to scale, and looking south. This is compared to the Sun on the winter solstice, December 21st. The orange line is the ecliptic, the Sun’s path in the sky. Created using Stellarium for the Moon and ecliptic with the Sun and annotations added.
This shows the actual angles of the Moon and Sun for comparison.
This shows the actual angles of the Moon and Sun for comparison.

As readers of this blog may have surmised, I’m facinated by angles in the sky.

Categories: Ephemeris Program, Observing, The Moon

Ephemeris: 09/16/2026 – Taking our weekly look at the whereabouts of the naked-eye planets

September 16, 2026 Comments off

This is Ephemeris for Wednesday, September 16th. Today the Sun will be up for 12 hours and 28 minutes, setting at 7:51, and it will rise tomorrow at 7:24. The Moon, 2 days before first quarter, will set at 10:08 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 8:15 tonight, about a half-hour after sunset, Venus will be spotted very low in the west southwestern sky with the moon above and to the left. Though at a 41º angle from the sun, it’ll only be 4º above the horizon then. A telescope will show a small crescent disk of the planet. It is now rapidly approaching earth in its orbit, at 41.2 million miles (66.3 mil km) away from us. Venus is becoming an ever decreasing crescent as its apparent diameter grows in telescopes. Saturn will rise at 8:47 PM in the east. At 6 AM, Mars and Jupiter will be in the east. Jupiter is brightest and lowest while Mars is just below and right of Pollux, the brightest star in Gemini.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Venus appears low in the west southwestern sky, with the crescent moon in the south southwest at 8:15 PM tonight, September 16, 2026.
Venus appears low in the west southwestern sky, with the crescent moon in the south southwest at 8:15 PM tonight, September 16, 2026. Created using Stellarium.
The Moon two days before first quarter at 10 PM tonight, September 16, 2026. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP. This presentation doesn’t work well on my Android phone.
The Moon two days before first quarter at 10 PM tonight, September 16, 2026.
The Moon two days before first quarter at 10 PM tonight, September 16, 2026. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP. Same as above, with an animated GIF. Answer in the comments, which you prefer.
Saturn appers in the east by 10 PM directly under the Great Square of Pegasus, the winged horse of Greek myth.
Saturn appers in the east by 10 PM directly under the Great Square of Pegasus, the winged horse of Greek myth. Created using Stellarium.
Mars and Jupiter appear with the stars of winter, now adorning the predawn sky at 6 AM.
Mars and Jupiter appear with the stars of winter, now adorning the predawn sky at 6 AM. Created using Stellarium.
Telescopic views of the naked-eye planets as seen in a small telescope.
Telescopic views of the naked-eye planets as seen in a small telescope: Venus’ apparent diameter at 8:15 PM tonight will be 38.5″, and be 26.8% illuminated. At 10 PM, Saturn will be 19.6″ in diameter, and its rings extend to 45.7″. At 6 AM, Jupiter will be 32.5″ in diameter. Mars, not shown, will appear 5.3″ in diameter. The (”) symbol means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts), LibreOffice Draw and GIMP.
The naked-eye planets at sunset and sunrise on a single night.
The naked-eye planets at sunset and sunrise on a single night, starting with sunset on the right on September 16, 2026. The night ends on the left with sunrise on the 17th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
The naked-eye planets, from Mercury to Saturn, in a low angle perspective view of the solar system from above and a bit beyond Saturn’s orbit for today, September 16, 2026.
The naked-eye planets, from Mercury to Saturn, in a low angle perspective view of the solar system from above and a bit beyond Saturn’s orbit for today, September 16, 2026. Created using my LookingUp app, text and arrows created using LibreOffice Draw and produced a unified image using GIMP.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

Ephemeris: 09/15/2026 – Two small but interesting constellations in and near the Summer Triangle

September 15, 2026 Comments off

This is Ephemeris for Tuesday, September 15th. Today the Sun will be up for 12 hours and 31 minutes, setting at 7:53, and it will rise tomorrow at 7:22. The Moon, 3 days before first quarter, will set at 9:34 this evening.

There are two small constellations in and near the Summer Triangle of bright stars. Both are near Altair the bottom star of the triangle in the south. The first is Delphinus the dolphin to the left of Altair. Delphinus is made-up of a small squished box of stars with another star below. It does look a dolphin leaping out of the water. The legendary Greek poet Arion, according to myth, was rescued by a dolphin. Also the little squished box is an asterism called Job’s Coffin, though no one knows the origin of that name. The second constellation is above Altair, and within the Summer Triangle. It is called Sagitta the arrow. The stars do line up to look like a short arrow. It’s supposed to represent Cupid’s dart.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Delphinus and Sagitta finder animation
Delphinus and Sagitta finder animation. Created using Stellarium and GIMP.
Comet West at 6 am, March 8, 1976
Comet West, C/1975 V1, as photographed by me at about 6 am, March 8, 1976. The wide, curved dust tail is most prominent with the narrow blue ion tail pointed more directly away fromthe rising Sun. The small summer constellation of Delphinus the dolphin is to the upper right. The diamond shape of stars at the front of the dolphin’s body is an asterism called Job’s Coffin.
Categories: Constellations, Mythology, Observing Tags: , ,

Ephemeris: 09/10/2026 – Finding Pegasus the winged horse of Greek myth

September 10, 2026 Comments off

This is Ephemeris for Thursday, September 10th. Today the Sun will be up for 12 hours and 46 minutes, setting at 8:02, and it will rise tomorrow at 7:17. The Moon is new today, and won’t be visible.

Saturn is low in the eastern sky at 10 PM. This is the brightest “star” in that direction. Above Saturn is the Great Square of Pegasus, a large, nearly perfect square of stars, standing on one corner. This is the front part of the body of Pegasus the flying horse. He’s climbing to the upper right, following the rotation of the sky. But it’s flying upside down, having its neck and head extend from the rightmost star of the square. From the top star are his forelegs extend. From the leftmost star extend two curved lines of stars which may look like hind legs, but belong to another constellation, Andromeda the Princess. Pegasus’ wings are not seen in the stars. Pegasus is part of a Greek myth, which has been made into two movies, both titled Clash of the Titans. But no actual Titans were used in the movies. All gods and godesses in the movie were their decendents.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Pegasus and Andromeda are seen above Saturn, the brightest "star" low in the east at 10 PM.
Pegasus and Andromeda are seen above Saturn, the brightest “star” low in the east at 10 PM. The star seemingly shared by both Pegasus and Andromeda is Alpheratz belongs to the lady. The unmarked W shaped group of stars to the upper left belong to Cassiopeia, Andromeda’s mother. It’s a long story. Created using Stellarium, LibreOffice Draw and GIMP.

Categories: Constellations, Ephemeris Program, Observing Tags: , ,

Ephemeris: 09/03/2026 – Finding the North American Nebula

September 3, 2026 Comments off

This is Ephemeris for Thursday, September 3rd. Today the Sun will be up for 13 hours and 8 minutes, setting at 8:15, and it will rise tomorrow at 7:08. The Moon, 1 day before last quarter, will rise at 11:15 this evening.

Most of what we see in the Milky Way are just masses of stars, but there are bright clouds of gas, or to name them properly: emission nebulae. These bright clouds are areas of star formation. It is the ultraviolet light from young massive stars that light up the clouds they were formed from. A bright one, easily visible in binoculars, is just about overhead at 10 p.m. Called the North American Nebula, a glow, that in photographs is shaped much like our continent, is just east of the star Deneb which is practically overhead in the evening. Deneb is the northernmost star of the Summer Triangle, and brightest star in Cygnus the swan or Northern Cross. There are many other nebulae in the Milky Way, visible in binoculars and small telescopes. Many enjoyable hours can be spent sweeping the Milky Way for nebulae and star clusters.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

The North American Nebula finder. Move slider to see the stars and Milky Way as they are seen in the sky and as annotated. Created using Stellarium.
Deneb & North American Nebula
One of my old photographs of Deneb and the North American Nebula digitized from a slide.
The North American Nebula
The North American (center left) and Pelican (right) nebulae is seen here in an astrophotograph by Daniel Dall’Olmo. The red color is due to the element hydrogen. Our eyes can’t perceive red very well with our night vision. However, hydrogen also emits in the green, which along with doubly ionized oxygen also emitting green light, makes it bright enough to be discerned visually. Click or tap on the image to enlarge it.

Categories: Deep Sky Object, Ephemeris Program, Nebulae, Observing Tags:

Ephemeris: 09/02/2026 – Taking our weekly look at the whereabouts of the naked-eye planets

September 2, 2026 Comments off

This is Ephemeris for Wednesday, September 2nd. Today the Sun will be up for 13 hours and 11 minutes, setting at 8:17, and it will rise tomorrow at 7:07. The Moon, 2 days before last quarter, will rise at 10:33 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 8:45 PM tonight, a nearly a half-hour after sunset, Venus will be spotted low in the west southwestern sky. Though at a 44º angle from the sun, it’ll only be 6º above the horizon then. A telescope will show a small crescent disk of the planet. It is now rapidly approaching earth in its orbit, at 50.8 million miles (81.8 mil km) away from us. Venus is becoming an ever decreasing crescent as its apparent diameter grows in telescopes. At 6 AM, Saturn will be alone in the southwest, while Mars and Jupiter will be in the east. Jupiter is brightest and lowest while Mars has the competition of brighter stars in Gemini.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Venus appears low in the west southwestern sky at 8:45 PM tonight
Venus appears low in the west southwestern sky at 8:45 PM tonight, September 2, 2026. Created using Stellarium.
Saturn, Mars, Jupiter and the Moon will be seen at 6:00 AM tomorrow morning September 3, 2026.
Saturn, Mars, Jupiter and the Moon will be seen at 6:00 AM tomorrow morning September 3, 2026. Mars, in Gemini, is entering the part of the sky with bright stars, the winter sky. So it won’t stand out until it gets much closer to the Earth. Jupiter is brighter than all the rest. Created using Stellarium.
Moon a day before last quarter at 6 AM tomorrow morning, September 3, 2026. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Venus at 8:45 PM tonight, September 2, 2026, and Saturn and Jupiter at 6:00 AM.
Telescopic Venus at 8:45 PM tonight, September 2, 2026, and Saturn and Jupiter at 6:00 AM on the 3rd (north up), as they would be seen in a small telescope with the same magnification. Venus’ apparent diameter will be 31.0″, and be 37.5% illuminated. Saturn will be 19.4″ in diameter, and its rings extend to 45.1″, and are tilted 8.6º to our view. Jupiter will be 31.9″ in diameter. Mars, not shown, will appear 5.1″ in diameter. The (”) symbol means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts), LibreOffice Draw and GIMP.
Telescopic Venus at 8:45 PM tonight, September 2, 2026, and Saturn and Jupiter at 6:00 AM.
The naked-eye planets at sunset and sunrise on a single night, starting with sunset on the right on September 2, 2026. The night ends on the left with sunrise on the 3rd. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
The naked-eye planets, from Mercury to Saturn, in a low angle perspective view of the solar system from above and a bit beyond Saturn’s orbit for today, September 2, 2026.
The naked-eye planets, from Mercury to Saturn, in a low angle perspective view of the solar system from above and a bit beyond Saturn’s orbit for today, September 2, 2026. Created using my LookingUp app, text and arrows created using LibreOffice Draw and produced a unified image using GIMP.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

Ephemeris: 09/01/2026 – Previewing September skies

September 1, 2026 Comments off

This is Bob Moler with Ephemeris for Tuesday, September 1st. Today the Sun will be up for 13 hours and 14 minutes, setting at 8:19, and it will rise tomorrow at 7:06. The Moon, 3 days before last quarter, will rise at 10:00 this evening.

Let’s look at the skies for the month of September, a transition month between summer and autumn. The Sun will be moving at its greatest speed in its retreat to the south. Daylight hours in the Interlochen/Traverse City area and will drop from 13 hours and 14 minutes today to 11 hours 45 minutes on the 30th. The altitude of the Sun above the southern horizon at local noon will be 54 degrees today, and will descend to 42 degrees on the 30th. The season of summer is getting short, so enjoy it while you can. Summer ends and autumn begins at 8:06 p.m. with the autumnal equinox on September 22nd. The Harvest Moon will occur on the 26th, being the closest full moon to the autumnal equinox.

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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

September Evening Star Chart

Star Chart for September 2026 (10 PM EDT, September 15).
Star Chart for September 2026 (10 PM EDT, September 15). Created using my LookingUp program.

The planets and stars are plotted for the 15th at 10 p.m. EDT in the evening and 6 a.m. for the morning chart. These are the chart times. Note that Traverse City is located approximately 45 minutes behind our time meridian, West 75° longitude. (An hour 45 minutes behind our daylight saving time meridian during EDT). To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes earlier than the current time.

September Morning Star Chart

Star Chart for September 2025 (6 am EDT, September 16)
Star Chart for September 2025 (6 am EDT, September 16). Click on the image to enlarge it. Created using my LookingUp program.

Twilight Limits, Nautical and Astronomical

      EDT        
  Morning Twilight Evening Twilight Dark Night Moon
Date Astro. Nautical Nautical Astro. Start End Illum.
2026-09-01 5h22m 6h00m 21h29m 22h07m – – 73%
2026-09-02 5h24m 6h02m 21h27m 22h05m 22h05m 22h33m 63%
2026-09-03 5h25m 6h03m 21h25m 22h03m 22h03m 23h16m 52%
2026-09-04 5h27m 6h05m 21h23m 22h00m 22h00m – 40%
2026-09-05 5h28m 6h06m 21h21m 21h58m 21h58m 0h11m 29%
2026-09-06 5h30m 6h07m 21h19m 21h56m 21h56m 1h20m 19%
2026-09-07 5h32m 6h09m 21h17m 21h54m 21h54m 2h37m 11%
2026-09-08 5h33m 6h10m 21h15m 21h51m 21h51m 3h58m 5%
2026-09-09 5h35m 6h11m 21h13m 21h49m 21h49m 5h18m 1%
2026-09-10 5h36m 6h13m 21h11m 21h47m 21h47m 5h36m 0%
2026-09-11 5h38m 6h14m 21h09m 21h45m 21h45m 5h38m 1%
2026-09-12 5h39m 6h15m 21h07m 21h43m 21h43m 5h39m 5%
2026-09-13 5h40m 6h17m 21h05m 21h41m 21h41m 5h40m 11%
2026-09-14 5h42m 6h18m 21h03m 21h38m 21h38m 5h42m 18%
2026-09-15 5h43m 6h19m 21h01m 21h36m 21h36m 5h43m 26%
2026-09-16 5h45m 6h20m 20h59m 21h34m 22h08m 5h45m 35%
2026-09-17 5h46m 6h22m 20h57m 21h32m 22h50m 5h46m 44%
2026-09-18 5h48m 6h23m 20h55m 21h30m 23h40m 5h48m 53%
2026-09-19 5h49m 6h24m 20h53m 21h28m – 5h49m 63%
2026-09-20 5h50m 6h25m 20h51m 21h26m 0h39m 5h50m 72%
2026-09-21 5h52m 6h27m 20h49m 21h24m 1h43m 5h52m 80%
2026-09-22 5h53m 6h28m 20h47m 21h22m 2h50m 5h53m 87%
2026-09-23 5h54m 6h29m 20h45m 21h20m 3h59m 5h54m 93%
2026-09-24 5h56m 6h31m 20h43m 21h18m 5h08m 5h56m 97%
2026-09-25 5h57m 6h32m 20h41m 21h16m – – 100%
2026-09-26 5h58m 6h33m 20h39m 21h13m – – 100%
2026-09-27 6h00m 6h34m 20h37m 21h11m – – 97%
2026-09-28 6h01m 6h35m 20h35m 21h09m – – 92%
2026-09-29 6h02m 6h37m 20h33m 21h08m – – 85%
2026-09-30 6h04m 6h38m 20h31m 21h06m 21h06m 21h15m 76%

Twilight calendar was generated using Cartes du Ciel (Sky Charts).

See my blog post: Twilight Zone for the definitions of the different periods of twilight here: https://bobmoler.wordpress.com/2018/09/27/.

NASA Calendar of Planetary Events

Date         Time     Event
Sep  1  Tu            Venus: 44.6° E
     1  Tu   9:27 AM  Venus-Spica: 1.4° S
     3  Th   8:03 AM  Moon-Pleiades: 1.2° S
     4  Fr   3:51 AM  Last Quarter
     5  Sa   2:12 AM  Moon North Dec.: 28.1° N
     6  Su   2:24 PM  Moon-Mars: 3° S
     6  Su   4:26 PM  Moon Perigee: 368300 km
     8  Tu  12:43 AM  Moon-Beehive: 0.5° S
     8  Tu   2:13 PM  Moon-Jupiter: 0.8° S
     9  We   3:17 PM  Moon Descending Node
    10  Th  11:27 PM  New Moon
    13  Su   4:53 PM  Moon-Spica: 2.6° N
    14  Mo   7:10 AM  Moon-Venus: 0.6° S
    16  We   9:42 PM  Mars-Pollux: 5.9° S
    17  Th   8:18 AM  Moon-Antares: 0.6° N
    18  Fr   2:54 PM  Moon South Dec.: 28.1° S
    18  Fr   4:44 PM  First Quarter
    18  Fr  11:00 PM  Moon Apogee: 404200 km
    22  Tu   8:06 PM  Autumnal Equinox
    23  We  10:40 PM  Moon Ascending Node
    25  Fr   8:13 PM  Neptune Opposition
    25  Fr   9:49 PM  Mercury-Spica: 0.9° N
    26  Sa  12:49 PM  Full Moon (Harvest Moon)
    30  We   1:39 PM  Moon-Pleiades: 1.1° S

Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC), with modifications by the author.
http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html.

If you go to the above site, you can print out a list like the above for the entire year or calendar pages for your time zone.

Categories: Ephemeris Program, Month preview, Observing Tags: