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Ephemeris: 09/18/2024 – Checking out where the naked-eye planets are this week

September 18, 2024 Comments off

This is Ephemeris for Wednesday, September 18th. Today the Sun will be up for 12 hours and 20 minutes, setting at 7:46, and it will rise tomorrow at 7:27. The Moon, 1 day past full, will rise at 8:08 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be spotted in the West southwest only 5° above the horizon at 8:15 or 30 minutes after sunset. It will set at 8:48. Saturn will be low in the east-southeast at that time, with the Moon just rising in the east. Saturn may look disappointing in telescopes this year since its rings are nearly edge on and appearing as a line through the planet like it’s stapled onto the sky. Jupiter and Mars will be up in the morning sky, with Jupiter rising before midnight now and by 6:30 AM tomorrow, Jupiter will be the brightest starlike object in the sky among the winter stars in the south-southeast. Mars will be left and below Jupiter.

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

Venus in evening twilight, approximately 30 minutes after sunset
Venus in evening twilight, approximately 30 minutes after sunset. For the Grand Traverse area of Michigan that would be about 8:15 PM, where Venus is very close to the horizon, due to the low angle of the ecliptic, even though Venus is about 27 degrees east of the sun, it is only 10 degrees above the horizon at sunset. It would be higher from the south of us, below 45° N latitude, and lower for those north of us. Created using Stellarium.
At the same time we see Venus setting in the West around 8:15 PM we see the Moon rise in the east, and Saturn close by in the east-southeast
At the same time we see Venus setting in the West around 8:15 PM we see the Moon rise in the east, and Saturn close by in the east-southeast. Saturn may not be quite as visible as this, but it will be shortly. Created using Stellarium.
The Moon one day past the full Harvest Moon
The Moon one day past the full Harvest Moon and shadows are beginning to creep onto the west, or right side of it. Created using Stellarium, LibreOffice Draw, and GIMP.
The morning planets Jupiter and Mars are seen among the winter stars
The morning planets Jupiter and Mars are seen among the winter stars at 6:30 AM or about an hour before sunrise in the South southeast. Created using stellarium.
Telescopic Venus, Saturn and Jupite
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. Venus and Saturn are from the evening of the 18th 2024, Jupiter is for 6:30 am on the 19th. Apparent diameters: Venus 11.7″, 87.6% illuminated; Saturn 19.2″, its rings 44.6″, 4.2 degrees from edge on (opening up a bit); Jupiter 40.7″; Mars, too small to be represented here, is 7.1″. The ” means seconds of arc, or 1/3600th of a degree. Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
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 18, 2024. The night ends on the left with sunrise on the 19th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
Low precision ephemeris
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, September 18 and 19, 2024. Some of the columns are self-explanatory, others 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, Planets Tags: , , , , ,

Ephemeris: 09/17/2024 – Super Harvest Moon Eclipse tonight

September 17, 2024 Comments off

Note: the eclipse isn’t that super, however tonight’s full moon is a supermoon, and the Harvest Moon to boot. On with the program.

This is Ephemeris for Tuesday, September 17th. Today the Sun will be up for 12 hours and 23 minutes, setting at 7:48, and it will rise tomorrow at 7:25. The Moon, at full today, will rise at 7:47 this evening.

Tonight’s full Harvest Moon* is also a supermoon and on top of that it will be partially eclipsed in Earth’s shadow. The Moon will just clip the bottom or south part of the Earth’s inner shadow called the umbra between 10:13 PM and 11:15 PM. Only 8% of the Moon’s diameter will be covered by the umbra at maximum eclipse at 10:44 PM. However, the Moon will spend a fair amount of time in the Earth’s penumbra, the outer part of the shadow, where the Sun is only partially blocked. So the moon will appear dimmer than normal at its upper parts from about 9:45 to 11:45 PM or so. Viewing the moon through a pair of sunglasses will enhance the effects of the dimming of the penumbra, cutting down the Moon’s glare.

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.

* The Harvest Moon is the full moon nearest the date of the autumnal equinox which this year is on the 22nd of September. What makes the Harvest Moon special is the Harvest Moon Effect. Check it out this previous post where I explained more about it: Here

Addendum

A preview of the Moon in five stages before during and after the eclipse
Here we have a preview of the Moon in five stages before during and after the eclipse. In time we’re moving from right to left just as the Moon moves against the background of the sky and the Earth’s shadow. Of course during all this period of time the Earth’s rotation is moving the sky in the opposite direction much faster. Be that as it may, before the Moon enters the Earth’s penumbra it is evenly eliminated by the Sun. At 10:18 PM the Moon has been immersed 5 minutes into the umbra so it’s taking a little bite out of its upper left part. The effect of the Moon being deeply immersed in the penumbra is also visible. Mid eclipse is at 10:44 PM. At 11:10 PM the Moon is 5 minutes before leaving the umbra. By 12:48 AM the Moon has cleared the penumbra and is again fully illuminated. Click or tap on the image to enlarge it. The Moon images were created using Stellarium, assembled using GIMP and annotated using LibreOffice Draw.
Categories: Astronomical Event, Ephemeris Program, Observing Tags: , , ,

Ephemeris: 09/12/2024 – Does the Moon have a square crater?

September 12, 2024 Comments off

This is Ephemeris for Thursday, September 12th. Today the Sun will be up for 12 hours and 39 minutes, setting at 7:58, and it will rise tomorrow at 7:19. The Moon, 1 day past first quarter, will set at 1:11 tomorrow morning.

I built my first telescope in the mid 1950s from the kit. It had a 5-inch diameter mirror. Of course one of the first things I looked at was the Moon. And while familiarizing myself with the Moon’s features I noticed that around first quarter moon there was a funny little crater near the Moon’s North Pole that looked square. All the other craters were round. This one being near the North Pole was foreshortened a bit, so it’ll look rectangular. It sure had walls that looked like they were straight rather than curved. The crater’s name is Barrow. And the description I found of it said it had an interesting shape, though they didn’t mention it was square. Looking closely at it, it is squarish but in small telescopes it definitely looks like it’s a square crater. The best time to try to spot it is around first quarter moon or up to a couple of days later.

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

Barrow crater view on the Moon tonight
The northern half of the moon as it might be seen tonight this recreation using Virtual Moon Atlas. The crater Barrow is pointed out which under low power almost appears to be square.
Overhead view of Barrow crater
In this overhead view also from the Virtual Moon Atlas the Barrow crater appears rounder, however it seems to be about halfway between being round and square.

The base imagery used for the Virtual Moon Atlas, I believe, came from the Clementine spacecraft, a joint project of NASA and the Department of Defense, which orbited the Moon for 71 days in the mid 90s and then was sent out to an asteroid. However, on the way to the asteroid a problem occurred and Clementine was “lost and gone forever”.

Categories: Ephemeris Program, Observing, The Moon Tags: ,

Ephemeris: 09/11/2024 – Where are the naked-eye planets now?

September 11, 2024 Comments off

This is Ephemeris for Wednesday, September 11th. Today the Sun will be up for 12 hours and 42 minutes, setting at 7:59, and it will rise tomorrow at 7:18. The Moon, at first quarter today, will set at 12:07 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be glimpsed low in the west around 8:20 PM. It will set at 8:56. It is best seen over a very low or lake horizon. By 9 PM the gibbous Moon will be low in the south. Saturn will be low in the east-southeast, pretty much by itself. Saturn may look disappointing in telescopes this year since its rings are nearly edge on and appearing as a line through the planet. Jupiter and Mars will be up in the east in the morning, and by 6:15 AM tomorrow, Jupiter will be the brightest starlike object in the sky among the winter stars in the southeast. Mars will be left and below Jupiter. Mercury might be spotted near the horizon in the east.

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

Venus in evening twilight, approximately 30 minutes after sunset
Venus in evening twilight, approximately 30 minutes after sunset. For the Grand Traverse area of Michigan that would be about 8:30 PM, where Venus Due to the low angle of the ecliptic, even though Venus is about 27 degrees east of the sun, it is only 10 degrees above the horizon at sunset. It would be higher from the south of us, below 45° N latitude, and lower for those north of us. Created using Stellarium.
Saturn as it would appear at 9 PM low in east southeast with the naked eye
Saturn as it would appear at 9 PM low in east southeast with the naked eye. It would seem to be pretty much alone in that sector of the sky of dim stars. Saturn is now officially an evening planet. Created using Stellarium.
The Moon as it might appear through a small telescope tonight
The Moon as it might appear through a small telescope tonight, September 11, 2024. Selected features are labeled. Created using stellarium, LibreOffice draw, and GIMP.
Mars and Jupiter among the bright winter stars
Mars and Jupiter among the bright winter stars, and above the constellation of Orion with its bright stars Betelgeuse and Rigel. Also visible is the rising Mercury at 6:00 AM tomorrow morning, September 12, 2024. Created using Stellarium.
Mars and Jupiter among the bright winter stars
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. Venus and Saturn are from the evening of the 11th, Jupiter is for 6 am on the 12th. Apparent diameters: Venus 11.4″, 89.2% illuminated; Saturn 19.2″, its rings 44.7″, 3.5 degrees from edge on (opening up a bit); Jupiter 39.7″; Mars, too small to be represented here, is 6.9″. Mercury, also too small 5.8 and 78.6% illuminated. The ” means seconds of arc, or 1/3600th of a degree. Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on September 11, 2024. The night ends on the left with sunrise on the 12th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
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 11 and 12 2024. Some of the columns are self-explanatory, others 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, Planets Tags: , , , , ,

Ephemeris: 09/09/2024 – The Sun’s sibling star?

September 9, 2024 Comments off

This is Ephemeris for Monday, September 9th. Today the Sun will be up for 12 hours and 48 minutes, setting at 8:03, and it will rise tomorrow at 7:16. The Moon, 2 days before first quarter, will set at 10:38 this evening.

The Sun was born from a cloud, a nebula, of mostly hydrogen and helium with traces of heavier elements. Astronomers consider any element heaver than helium a metal. It was not born alone, but with many other stars in a star cluster, all at about the same time. The elements that are in the Sun’s atmosphere came from that nebula. Astronomers are wondering if there were any other stars they could see which were siblings of the Sun. Apparently they found one star that has the same metals in the same proportions as the Sun. That star is HD 162826, a dim star in the constellation Hercules, visible in binoculars. It’s a bit more massive than the Sun, and about 109 light years away. The Sun’s sibling stars have scattered far and wide.

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

Zooming in to the Sun's possible sibling star HD 87382 in Hercules
Zooming in to the Sun’s possible sibling star HD 162826 in Hercules. Getting closer, it’s part of a three star arc easily visible in binoculars, and is the dimmest at 6.5 magnitude. The brightest, at one end, is fifth magnitude the center star is 6, and our possible sibling star is at the end. Note that the dimmer the star the higher the magnitude. It may not make sense but it’s just like golf scores the lower the number of strokes the better the score. In astronomy the lower the magnitude the brighter the star, even into negative numbers, and vice versa. Created using Stellarium, and GIMP.
Categories: Binoculars, Ephemeris Program, Observing, Stars, The Sun Tags: ,

Ephemeris: 09/04/2024 – Where are the naked-eye planets this week?

September 4, 2024 Comments off

This is Ephemeris for Wednesday, September 4th. Today the Sun will be up for 13 hours and 3 minutes, setting at 8:12, and it will rise tomorrow at 7:10. The Moon, 2 days past new, will set at 8:53 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be glimpsed low in the west around 8:30 PM. It will set at 9:08. It is best seen over a very low or lake horizon. The thin sliver of the Moon might be seen below and to the right. Saturn will rise shortly after sunset, and by 9 PM will be low in the east-southeast, pretty much by itself. Saturn may look disappointing in telescopes this year since its rings are nearly edge on and appearing as a line through the planet. Jupiter and Mars will be up in the east in the morning, and by 6 am tomorrow, Jupiter will be the brightest starlike object in the sky among the winter stars. Mars will be just below it to the left. Mercury might be spotted near the horizon in the east, now and for the next week.

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

Venus and the Moon in evening twilight, approximately 20 minutes after sunset
Venus and the Moon in evening twilight, approximately 20 minutes after sunset. For the Grand Traverse area of Michigan that woud be about 8:30 PM, where Venus would be about 6 1/2 degrees above the horizon and the Moon 3 1/2 degrees. They would be higher from the south of us, below 45° N latitude, and lower for those north of us. Created using Stellarium.
Moon as it might be seen in the small telescope or binoculars at 8:30 PM
This is the Moon as it might be seen in the small telescope or binoculars at 8:30 PM tonight, September 4th 2024. It will be very low and difficult to spot. Also it might be exhibiting earthshine as seen here in this image. Created using Stellarium.
Saturn as it would appear at 10 PM low in east southeast with the naked eye
Saturn as it would appear at 10 PM low in east southeast with the naked eye. It would seem to be pretty much alone in that sector of the sky of dim stars. Saturn will be in opposition to the Sun in three days, on Saturday evening. After which it will officially become an evening planet. Created using Stellarium.
An animated morning planet finder for 6:00 AM or about an hour before sunrise
An animated morning planet finder for 6:00 AM or about an hour before sunrise. Three frames: The first shows the sky as it may appear in the east southeast with no labels. The second frame labels the bright stars and planets. The third frame shows the planets and the constellation outlines. Created using Stellarium and GIMP.
Telescopic Venus, Saturn and Jupiter
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. Venus and Saturn are from the evening of the 4th, Jupiter is for 6 am on the 29th. Apparent diameters: Venus 11.1″, 90.4% illuminated; Saturn 19.2″, its rings 44.7″, 3.7 degrees from edge on (opening up a bit); Jupiter 37.0″; Mars, too small to be represented here, is 6.7″. Mercury, also too small 7.2″ and 46.6% illuminated. The ” means seconds of arc, or 1/3600th of a degree. Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on September 4th, 2024. The night ends on the left with sunrise on the 5th
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on September 4th, 2024. The night ends on the left with sunrise on the 5th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
This is 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 4 and 5 2024. Some of the columns are self-explanatory, others 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, Planets Tags: , , , , ,

Ephemeris: 08/30/2024 – Star party tomorrow night

August 30, 2024 Comments off

This is Ephemeris for Friday, August 30th. Today the Sun will be up for 13 hours and 18 minutes, setting at 8:22, and it will rise tomorrow at 7:04. The Moon, 3 days before new, will rise at 4:11 tomorrow morning.

Weather permitting, a Star Party will be held tomorrow night at the Sleeping Bear Dunes National Lakeshore at the Dune Climb. The viewing will start at 9 pm. These events will be hosted by the park rangers and the Grand Traverse Astronomical Society, who will bring their telescopes to view the heavens, including the planet Saturn and the wonders of the summer Milky Way. The telescopes will be setup in the parking area closest to the dune. While twilight fades Saturn will be about the only object to view in the east-southeast. As it gets darker more and more wonders of the Milky Way will be seen. They include star clusters and nebulae, clouds of gas and dust that lie in abundance in the Milky Way.

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

Setting up for a star party the Dune Climb
Setting up for a star party the Dune Climb. A few of the telescopes are visible including the GTAS 25 inch “Emmettron” telescope at the far right background. Credit: Eileen Carlisle.
Categories: Ephemeris Program, GTAS Outreach Event, Observing, Star Party Tags: , ,

Ephemeris: 08/28/2024 – Where are the naked-eye planets this week?

August 28, 2024 Comments off

This is Ephemeris for Wednesday, August 28th. Today the Sun will be up for 13 hours and 24 minutes, setting at 8:25, and it will rise tomorrow at 7:02. The Moon, 2 days past last quarter, will rise at 1:55 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be glimpsed low in the west around 8:45 PM. It will set at 9:19. It is best seen over a very low or lake horizon. Saturn will rise at 8:52 pm, and by 10 pm will be low in the east-southeast, pretty much by itself. Saturn may look disappointing in telescopes this year since its rings are nearly edge on and appear almost as a line through the planet. Jupiter and Mars will be up in the east in the morning, and by 6 am tomorrow, Jupiter will be the brightest starlike object in the sky among the winter stars. Mars will be just below it to the left. And the waning crescent Moon below left of Mars. Jupiter will rise at 12:42 AM, with Mars rising at 1:09 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

This is what Venus might look like 20 minutes after sunset
This is what Venus might look like 20 minutes after sunset or around 8:45 PM tonight, August 28, 2024 in northwestern lower Michigan, looking over a Lake Michigan horizon. Created using Stellarium.
Saturn as it might be seen low in the east southeast at 9:30 PM
Saturn as it might be seen low in the east southeast at 9:30 PM tonight, August 28, 2024. Created using Stellarium.
Mars and Jupiter among the bright winter stars
Mars and Jupiter among the bright winter stars, and above the constellation of Orion with its bright stars Betelgeuse and Rigel. Also visible is the waning crescent Moon and the rising Mercury at 6:00 AM tomorrow morning, August 29th 2024. Created using Stellarium.
The Moon as it might appear through a small telescope
The Moon as it might appear through a small telescope tomorrow morning, August 29th 2024. Selected features are labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Venus, Saturn and Jupiter
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. Venus and Saturn are from the evening of the 28th, Jupiter is for 6 am on the 29th. Apparent diameters: Venus 10.9″, 91.7% illuminated; Saturn 19.2″, its rings 44.6″, 3.4 degrees from edge on (opening up a bit); Jupiter 38.2″; Mars, too small to be represented here, is 6.2″. Mercury, also too small 8.9 and 18.5% illuminated. Notes: Jupiter’s moon Io will be visible until 5:42 AM. It will not be visible as shown at 6 AM. The ” means seconds of arc, or 1/3600th of a degree. Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
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 28, 2024. The night ends on the left with sunrise on August 29th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
This is 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 28 and 29 2024. Some of the columns are self-explanatory, others 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 by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , ,

Ephemeris: 08/22/2024 – Saturn’s ring aspect is changing in the next nine months

August 22, 2024 Comments off

This is Ephemeris for Thursday, August 22nd. Today the Sun will be up for 13 hours and 41 minutes, setting at 8:36, and it will rise tomorrow at 6:55. The Moon, 3 days past full, will rise at 10:07 this evening.

Saturn graces our evening skies now, but it’s not yet in the evening planet. It will rise tonight at 9:16 PM. However, will set after sunrise, thus still being a morning planet. It will become an evening planet on September 7th, when it reaches opposition from the Sun. It will rise approximately the same time the Sun sets and thereafter will rise before sunset. Saturn’s rings are nearly edge on to us now. Currently, about 2 1/4° from being edge on. They will open up slightly over the next few months to five degrees on November 11th before closing up and becoming edge-on on March 23rd of next year. On that day the rings will disappear for us. However, their presence will only be seen by the thin shadow they cast on the planet.

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

The image shows Saturn and its rings on five date
Explanation below. Created using Stellarium, Libreoffice Draw and GIMP.

The image shows Saturn and its rings on five dates. The first is today, August 22nd 2024. On this date the rings are a little over three degrees from being edge on to us. They will actually open up a bit for nearly three months. On November 11th they will open up to nearly 6°. On March 23rd next year they will be exactly edge on to us and be invisible. The only sign of their presence will be a very thin shadow the rings cast on the planet. The bad part of this is that early next year Saturn will be too close to the Sun to be easily seen from Earth. That includes the Hubble and James Webb space telescopes. It will appear only 10 degrees west of the Sun on that date. It will increase over the next 44 days to 48 degrees on May 6th, when the rings will be edge on to the Sun. In that period the Earth will be looking at the unlit side of the rings. So the rings will be very dim. Only the light filtering through the rings will be seen, and the B ring which is the brightest normally will be just about completely dark due to the density of ring particles in it. After that the rings will open up for the next 7 1/2 years.

Categories: Ephemeris Program, Observing Tags:

Ephemeris: 08/21/2024 – What naked-eye planets are now visible?

August 21, 2024 Comments off

This is Ephemeris for Wednesday, August 21st. Today the Sun will be up for 13 hours and 44 minutes, setting at 8:37, and it will rise tomorrow at 6:54. The Moon, 2 days past full, will rise at 9:46 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be glimpsed low in the west with Venus lower in the west around 9:15 pm. It will set at 9:31. It is best seen over a very low or lake horizon. Saturn will rise at 9:21 pm, and by 10:30 pm will be low in the east southeast, pretty much by itself. Saturn may look disappointing in telescopes this year since rings are nearly edge on and appear almost as a line through the planet. Jupiter and Mars will be up in the east in the morning, and by 6 am tomorrow, Jupiter will be the brightest starlike object in the sky among the winter stars. Mars will be just below it to the left. Jupiter will rise at 1:06 am, with Mars rising 13 minutes later.

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

The planet Venus low in the West, above a lake horizon about 40 minutes after sunset
The planet Venus low in the West, above a lake horizon about 40 minutes after sunset or about 9:15 PM, August 21st 2024. Created using Stellarium.
Saturn and the Moon low in the eastern sky at 10:30 PM
Saturn and the Moon low in the eastern sky at 10:30 PM. Created using Stellarium.
The Moon as it might appear through a small telescope tonight, August 21st 2024. Selected features are labeled.
The Moon as it might appear through a small telescope tonight, August 21st 2024. Selected features are labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Mars and Jupiter along with the bright stars of winter
Mars and Jupiter along with the bright stars of winter seen at 6:00 tomorrow morning or nearly an hour before sunrise, August 22nd 2024. Created using Stellarium.
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. Venus is from 9:15 PM, Saturn is for 11 pm on the 21st, Jupiter is 6 am on the 22nd. Apparent diameters: Venus 10.7″; Saturn 19.1″, its rings 44.5″, 3.1 degrees from edge on (opening up a bit); Jupiter 37.5″; Mars, too small to be represented here, is 6.3″. Notes: Jupiter’s moon Io will be visible in the morning until 3:49 AM when it passes behind the planet or in its shadow. The ” means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts).
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 21, 2024. The night ends on the left with sunrise on August 22nd. The tags for Jupiter and Mars overlap a bit in Taurus due to their near conjunction. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
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 21 and 22 2024. Some of the columns are self-explanatory, others 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. Dec is declination which is the north-south position of the object on the celestial sphere. 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 by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , ,