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Ephemeris: 09/24/2025 – Taking our weekly look at the whereabouts of the naked-eye planets

September 24, 2025 Comments off

This is Ephemeris for Wednesday, September 24th. Today the Sun will be up for 12 hours and 3 minutes, setting at 7:35, and it will rise tomorrow at 7:33. The Moon, 3 days past new, will set at 8:27 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Saturn now rises about sunset in the east. It was in opposition from the Sun last Sunday. In a telescope Saturn sports a very thin ring, 1.7° from being edge on. Saturn has an axial tilt of about 27°, so it has seasons like the Earth and since its rings are over its equator, when they go edge on to the Sun, it is an equinox for it, which happened this past May. Earth, being close to the Sun, see nearly the same thing. Now the ring angle for us will decrease to about a third of a degree by November 23rd before increasing. By 6:30 AM Jupiter will appear high in the east-southeast, under the stars of Gemini. With brighter Venus low in the east below the star Regulus in Leo.

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, low in the east, is below and a bit right of the Great Square of Pegasus
Saturn, low in the east, is below and a bit right of the Great Square of Pegasus, which stands on one corner at 9 PM tonight, September 24, 2025. Created using Stellarium.
Venus and Jupiter are visible in the east among the winter stars at 6:30 AM
Venus and Jupiter are visible in the east among the winter stars at 6:30 AM tomorrow morning, September 25, 2025. Created using Stellarium.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification. On the evening of the September 24th 2025, Saturn will be 19.4″ in diameter, but its rings, even being nearly edge on, should show up brighter than seen here, and extend to 45.3″. They are tilted 1.7° from being edge on. At 6:30 AM on the morning of September 25th 2025, Jupiter will be 36.4″ in diameter. Europa will be eclipsed by Jupiter starting 4:41 AM, Ganymede will disappear into Jupiter’s shadow at 12:15 AM, and reappear at 3:19 AM, only to dissappear behind the planet at 4:20 AM. Venus’ apparent diameter will be 11.3″, and be 90.0% illuminated. It’s on the far side of the Sun. 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 and the Moon at sunset and sunrise on a single night, starting with sunset on the right on September 24th, 2025. The night ends on the left with sunrise on the 25th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, September 24th and 25th, 2025.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, September 24th and 25th, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

Ephemeris: 09/23/2025 – Neptune is at opposition today

September 23, 2025 Comments off

This is Ephemeris for Tuesday, September 23rd. Today the Sun will be up for 12 hours and 6 minutes, setting at 7:37, and it will rise tomorrow at 7:32. The Moon, 2 days past new, will set at 8:07 this evening.

I normally don’t talk about observing things in the sky unless it can be seen with the naked eye, or can be seen in binoculars which are near stars that are visible to the naked eye. So I rarely talk about the planet Neptune. The last time was eight years ago and for the same reason as today. Neptune is in opposition with the Sun. That is, it is exactly opposite to the Sun in the sky, rising at sunset and setting at sunrise. Not only that, today is the 179th anniversary of the date it was discovered in 1846. Interestingly, it was first seen by Galileo. In one of his drawings of Jupiter and its moons that he made with his small telescope, there happened to be a background star that he recorded. That star turned out to be Neptune.

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

Naptune as seen from Voyager 2 and the James Webb Space Telwescope.
Neptune as seen from Voyager 2 and the James Webb Space Telescope. The Voyager image is on the left . The reason the images appear so different is that the Voyager image was taken in visible light while the James Webb image is in the infrared. It allows the detector to pick up Neptune’s faint rings, features and moons more easily. Neptune is 30 times the Earth’s distance from the Sun, and it takes 165 years to orbit the Sun. Credit NASA/JPL.

Categories: Anniversary, Ephemeris Program, Infrared Astronomy, Planets Tags:

Ephemeris: 09/17/2025 – Taking a look at the whereabouts of the naked-eye planets

September 17, 2025 Comments off

This is Ephemeris for Wednesday, September 17th. Today the Sun will be up for 12 hours and 24 minutes, setting at 7:49, and it will rise tomorrow at 7:25. The Moon, 3 days past last quarter, will rise at 3:44 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Saturn now rises at 8:01 PM in the east. In a telescope Saturn sports a very thin ring, 2° from being edge on. Saturn has an axial tilt of about 27°, so it has seasons like the Earth and since its rings are over its equator, when they go edge on to the Sun, it is an equinox for it, which happened in May. Earth being close to the Sun and moving, see nearly the same thing. Now the ring angle for us will decrease to about a third of a degree by November 23rd before increasing. By 6 AM Jupiter will appear above the brighter Venus in the Eastern sky and among the stars of Gemini. Venus and Jupiter will have the waning crescent Moon between them tomorrow morning.

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, low in the east, below and a bit right of the Great Square of Pegasus, which stand on one corner. Created using Stellarium.
Venus, the waning crescent Moon and Jupiter are visible in the east among the winter stars at 6:00 AM tomorrow morning, September 18, 2025. Saturn is low in the west.
Venus, the waning crescent Moon and Jupiter are visible in the east among the winter stars at 6:00 AM tomorrow morning, September 18, 2025. Saturn is low in the west. Created using Stellarium.
The waning crescent Moon with earth shine.
The waning crescent Moon with earth shine on the morning of September 18, 2025. Not much detail can be made out in binoculars otherwise.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification. On the evening of the September 17th 2025, Saturn will be 19.4″ in diameter, but its rings, even being nearly edge on, should show up brighter than seen here, and extend to 45.3″. They are tilted 2.0° from being edge on. On the morning of September 19th 2025, Jupiter will be 35.7″ in diameter. Europa is eclipsed by Jupiter, Io will begin its transit the face of Jupiter at 5:44 AM and will be nearly impossible to spot against the planet. Venus’ apparent diameter will be 11.5″, and be 88.8% illuminated. It’s on the far side of the Sun. 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 and the Moon at sunset and sunrise on a single night
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on September 17th, 2025. The night ends on the left with sunrise on the 18th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, September 17th and 18th, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

Ephemeris: 09/10/2025 – Our weekly look at the naked-eye planets

September 10, 2025 Comments off

This is Bob Moler with Ephemeris for Wednesday, 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, 3 days past full, will rise at 9:14 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Saturn now rises at 8:30 PM in the east. In a telescope Saturn sports a very thin ring, 2¼° from being edge on. Saturn has an axial tilt of about 27°, so it has seasons like the Earth and since its rings are over its equator, when the go edge on to the Sun, it is an equinox for it, which happened in May. Earth being close to the Sun and moving, see nearly the same thing. Now the ring angle will decrease to about a third of a degree by November 23rd before increasing. By 6 AM Jupiter will appear above the brighter Venus in the eastern sky and among the stars of Gemini. Venus and Jupiter are joining the bright winter stars, a beautiful sight in the 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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Saturn and the Moon at 10 PM tonight
Saturn and the Moon at 10 PM tonight, September 10, 2025. Created using Stellarium.
The Moon tonight, September 10, 2025. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Venus and Jupiter are visible in the east among the winter stars at 6:00 AM tomorrow morning
Venus and Jupiter are visible in the east among the winter stars at 6:00 AM tomorrow morning, September 11, 2025. Saturn is off in the west-southwest. Created using Stellarium and GIMP.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification. On the evening of the September 10th 2025, Saturn will be 19.4″ in diameter, but its rings, even being nearly edge on, should show up brighter than seen here, and extend to 45.2″. They are tilted 2.2° from being edge on. On the morning of the September 11th 2025, Jupiter will be 35.1″ in diameter. Earlier in the morning Io and its shadow will transit the face of Jupiter. Venus’ apparent diameter will be 11.8″, and be 86.9% illuminated. 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 and the Moon at sunset and sunrise on a single night
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on September 10th, 2025. The night ends on the left with sunrise on the 11th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, September 10th and 11th, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

Ephemeris: 09/03/2025 – Our weekly look at the naked-eye planets

September 3, 2025 2 comments

This is Ephemeris for Wednesday, September 3rd. Today the Sun will be up for 13 hours and 7 minutes, setting at 8:15, and it will rise tomorrow at 7:09. The Moon, 3 days past first quarter, will set at 3:04 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. The Red Planet Mars is too close to the direction of the Sun to spot. This is the curse of trying to view evening planets, which are near the direction of the Sun in late summer and early fall, for us at higher latitudes. Saturn now rises at 8:58 PM in the east. In a telescope Saturn sports a very thin ring, 2 ½° from being edge on. This angle will decrease to about a third of a degree by November 23rd before increasing. By 6 AM Saturn will be in the southwest. Jupiter will appear above the brighter Venus in the eastern sky and among the stars of Gemini. Venus and Jupiter are joining the bright winter stars, a beautiful sight in the 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; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Saturn and the Moon at 10 PM tonight
Saturn and the Moon at 10 PM tonight, September 3, 2025. Created using Stellarium.
The Moon tonight, September 3, 2025. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Venus and Jupiter are visible in the east among the winter stars at 6:00 AM tomorrow morning
Venus and Jupiter are visible in the east among the winter stars at 6:00 AM tomorrow morning, September 4, 2025. Saturn is off in the west-southwest. Created using Stellarium and GIMP.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification. On the evening of the September 3rd 2025, Saturn will be 19.4″ in diameter, but its rings, even being nearly edge on, should show up brighter than seen here, and extend to 45.1″. They are tilted 2.5° from being edge on. On the morning of the September 4th 2025, Jupiter will be 35.0″ in diameter. Venus’ apparent diameter will be 12.1″, and be 85.2% illuminated. 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 and the Moon at sunset and sunrise on a single night
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on September 3rd, 2025. The night ends on the left with sunrise on the 4th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, September 3rd and 4th, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

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

Ephemeris: 08/29/2025 – Late August crescent Moon stays low in the western sky

August 29, 2025 Comments off

This is Ephemeris for Friday, August 29th. Today the Sun will be up for 13 hours and 22 minutes, setting at 8:24, and it will rise tomorrow at 7:03. The Moon, 2 days before first quarter, will set at 10:48 this evening.

There’s an interesting feature that I’ve noticed about the Moon this time of year. When there’s a waxing crescent Moon in the evening, in late summer to early autumn, it’s seen pretty low in the southwestern sky after sunset. Tonight it’ll be two days before first quarter so it’ll be a fat crescent. However, when it’s seen after sunset, it will be very low in the southwestern sky. Contrast that for early risers, at this time of year the waning crescent Moon moves at a steep angle to the horizon, as do the planets now in the east. And of course the opposite is true for late winter and early spring moons. By the way, the Harvest Moon is in early October this year. The Harvest Moon is the nearest 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

Daily position of the crescent Moon on four dates in late August, 2025. The Moon is shown 3 times normal size for clarity. Created using Stellarium, GIMP and LibreOffice Draw.
This is the planert and Moon line up from the morning of a couple of weeks ago. Note the steep line of the planets. The Planets motion closely follows the ecliptic (Sun’s path) as does the Moon.

Categories: Concepts, Ephemeris Program, Observing, Planets, The Moon

Ephemeris: 08/27/2025 – Taking our weekly look at the whereabouts of the naked-eye planets

August 27, 2025 Comments off

This is Ephemeris for Wednesday, August 27th. Today the Sun will be up for 13 hours and 28 minutes, setting at 8:27, and it will rise tomorrow at 7:00. The Moon, halfway from new to first quarter, will set at 10:02 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. The Red Planet Mars is too close to the direction of the Sun to spot. This is the curse of trying to view evening planets, which are near the direction of the Sun in late summer and early fall, for us at higher latitudes. Saturn now rises at 9:27 PM in the east. In a telescope Saturn sports a very thin ring, a bit more than 3° from being edge on. This angle will decrease to about a third of a degree by November 23rd before increasing. By 6 AM Saturn will be in the southwest. Jupiter will appear above the brighter Venus in the Eastern sky And among the brighter winter stars. Mercury will be in line with Venus and Jupiter very near the horizon.

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 Moon tomorrow morning, July 28, 2025. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Saturn is seen low in the east at 10:30 PM tonight
Saturn is seen low in the east at 10:30 PM tonight, August 27, 2025. Created using Stellarium.
Three of the four morning planets are visible in the east at 6:00 AM tomorrow morning
Three of the four morning planets are visible in the east at 6:00 AM tomorrow morning, August 28, 2025. Saturn is off in the southwest. Mercury may not actually be visible. Created using Stellarium and GIMP.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification. On the evening of the August 27th 2025, Saturn will be 19.5″ in diameter, but its rings, even being nearly edge on, should show up brighter than seen here, and extend to 44.8″. They are tilted 2.7° from being edge on. On the morning of the August 28st 2025, Jupiter will be 34.1″ in diameter. Venus’ apparent diameter will be 12.5″, and be 83.4% illuminated. Mercury, too small to be shown here, is 5.9″ in diameter, and 77.1% illuminated. The ” 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 and the Moon at sunset and sunrise on a single night
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on August 27, 2025. The night ends on the left with sunrise on the 28th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, August 27th and 28th, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

Ephemeris: 08/20/2025 – Taking our weekly look at the whereabouts of the naked-eye planets

August 20, 2025 Comments off

This is Ephemeris for Wednesday, August 20th. Today the Sun will be up for 13 hours and 48 minutes, setting at 8:39, and it will rise tomorrow at 6:52. The Moon, 3 days before new, will rise at 4:41 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. The Red Planet Mars is too close to the direction of the Sun to spot. This is the curse of trying to view evening planets, which are near the direction of the Sun in late summer and early fall, for us at higher latitudes. Saturn now rises at 9:55 PM in the east. In a telescope Saturn sports a very thin ring, a bit less than 3° from being edge on. By 6 AM Saturn will be in the southwest. Jupiter will appear above the brighter Venus in the Eastern sky And among the brighter winter stars. Venus is by far the brighter of the two planets. Mercury will be below the crescent Moon tomorrow morning.

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 is seen low in the east at 11 PM tonight
Saturn is seen low in the east at 11 PM tonight, August 20, 2025. It’s below the Great Square of Pegasus seen standing on one corner above and left of it. Created using Stellarium.
Three of the four morning planets are visible, along with the crescent Moon, in the east at 6:00 AM tomorrow morning, August 21, 2025.
Three of the four morning planets are visible, along with the crescent Moon, in the east at 6:00 AM tomorrow morning, August 21, 2025. Saturn is off in the southwest. Mercury will be visible for the next few days before it heads back toward the Sun. The Moon needed a bit of cosmetic surgery to have it show up better. Stellarium doesn’t handle real thin crescent moon images well at this small of a scale. Created using Stellarium and GIMP.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification. On the morning of the August 21st 2025, Saturn will be 19.1″ in diameter, but its rings, even being nearly edge on, should show up brighter than seen here., and extend to 44.5″. They are tilted 2.9° from being edge on. Jupiter will be 33.6″ in diameter. Venus’ apparent diameter will be 12.9″, and be 81.4% illuminated. Mercury, too small to be shown here, is 7.0″ in diameter, and 49.9% illuminated. The ” 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 and the Moon at sunset and sunrise on a single night, starting with sunset on the right on August 20, 2025. The night ends on the left with sunrise on the 21st.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on August 20, 2025. The night ends on the left with sunrise on the 21st. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, August 20th and 21st, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,

Ephemeris: 08/19/2025 – Mercury makes its morning appearance

August 19, 2025 Comments off

This is Ephemeris for Tuesday, August 19th. Today the Sun will be up for 13 hours and 51 minutes, setting at 8:41, and it will rise tomorrow at 6:51. The Moon, 3 days past last quarter, will rise at 3:25 tomorrow morning.

The tiny planet Mercury is making an appearance in the morning sky now. For the next week or so it will be visible around 6 AM. At least it’s time to start looking for it. Once found, it might be followed for another 20 minutes or so. This morning Mercury was at its greatest angular separation or elongation from the Sun of 18.6°. We have two periods where Mercury is easier to spot: on late winter and early spring evenings, and in the morning sky in late summer and early autumn. Of course Mercury must be at the proper elongation point at the time. Mercury is the smallest of the planets, being only 50% larger in diameter than our moon. In closeup, it looks much like our Moon, gray and cratered.

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 planets Mercury, Venus, and Jupiter along with the Moon as they would appear tomorrow morning August 20th at 6:00 AM in the eastern sky
The planets Mercury, Venus, and Jupiter along with the Moon as they would appear tomorrow morning August 20th at 6:00 AM in the eastern sky. Also for Northern Michigan observers, at exactly 6:00 AM, the International Space Station will be cruising past these planets as it moves to set in the east-northeast. Created using Stellarium.
Categories: Ephemeris Program, Mercury, Naked-eye planets Tags:

Ephemeris: 08/13/2025 – Taking our weekly look at the whereabouts of the naked-eye planets

August 13, 2025 Comments off

This is Bob Moler with Ephemeris for International Left-handers Day, Wednesday, August 13th. Today the Sun will be up for 14 hours and 7 minutes, setting at 8:51, and it will rise tomorrow at 6:44. The Moon, 3 days before last quarter, will rise at 10:47 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. The Red Planet Mars is getting so low in the western sky in evening twilight that I’ve given up on trying to spot it. This is the curse of trying to view evening planets, which are near the direction of the Sun in late summer and early fall, for us at higher latitudes. Mars won’t pass behind the Sun and enter the morning sky until January 9th. Saturn now rises at 10:23 PM in the east. In a telescope Saturn sports a very thin ring, less than 4° from being edge on. By 5:30 AM Saturn will be high in the south, when our winter pal Orion will be rising. Venus and Jupiter will appear very close. Venus is by far the brighter of the two.

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

Mars and Spica this evening in the western sky an hour after sunset
Mars and Spica this evening in the western sky an hour after sunset here (9:51 PM), August 13, 2025. With the smoke from the Canadian wild files, I doubt any stars or planets could be seen near the horizon. Created using Stellarium.
Saturn, Jupiter and Venus with some bright winter stars at 5:45 AM tomorrow morning
Saturn, Jupiter and Venus with some bright winter stars at 5:45 AM tomorrow morning, August 14th, 2025, looking from east-northeast to southwest. Created using Stellarium.
The Moon tomorrow morning, August 14, 2025. A view visible in small telescopes showing an image with and without selected features labeled. Feature labels are centered. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Saturn, Jupiter and Venus as they would be seen in a small telescope with the same magnification
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification. On the morning of the August 14th 2025, Saturn will be 19.0″ in diameter, but its rings, even being nearly edge on, should show up brighter than seen here., and extend to 44.2″. They are tilted 3.1° from being edge on. Jupiter will be 33.3″ in diameter. Venus’ apparent diameter will be 13.3″, and be 79.4% illuminated. The ” 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 and the Moon at sunset and sunrise on a single night
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on August 13, 2025. The night ends on the left with sunrise on the 14th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, August 13th and 14th, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

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