Archive
12/08/2021 – Ephemeris – Let’s search for the naked-eye planets and a comet for this week
This is Ephemeris for Wednesday, December 8th. Today the Sun will be up for 8 hours and 54 minutes, setting at 5:02, and it will rise tomorrow at 8:08. The Moon, 2 days before first quarter, will set at 10:00 this evening.
Let’s search for the naked-eye planets for this week. Venus will be visible in the southwestern evening twilight by 5:30 tonight. It’s a crescent in telescopes. It is moving closer to us, and now appears larger than Jupiter in telescopes. Venus will set at 7:41 pm. By 5:45 pm, both Jupiter and Saturn should be able to be spotted in the southwestern sky. Saturn will be dimmer, and to its lower right, between it and Venus. It will set at 9:05 pm, with Jupiter following an hour and a half later at 10:34 pm. Comet Leonard can be spotted with binoculars about 19 degrees below and a bit left of the bright star Arcturus in the east from 6 to 7am tomorrow morning. 19 degrees is a bit less than two widths of a fist held at arm’s length. The comet will move lower each morning.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum

The evening planets Venus, Saturn, the Moon and Jupiter at 5:45 pm this evening, December 8, 2021. Created using Stellarium.

Comet Leonard and Mars at 7:15 am tomorrow morning, December 9, 2021. Though technically visible to the naked eye, binoculars will be needed for most of us. Mars is now visible low in the southeast at that time. Created using Stellarium.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 6 pm, December 8, 2021. Apparent diameters: Venus, 44.08″, 21.5% illuminated; Saturn 15.84″, its rings 36.90″; Jupiter, 37.51″. Mars is not shown, its apparent diameter is 3.82″. The ” symbol means seconds of arc (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, starting with sunset on the right on December 8, 2021. The night ends on the left with sunrise on the 9th. Click on the image to enlarge it. Created using my LookingUp program.

Comet Leonard’s positions at 6:30 am on the dates indicated. The labels are Month-Day Total Magnitude. The star’s position relative to the horizon and the position of Mars are for November 27th. The star field will be shifting to the upper right each morning at 6:30 from the November 27th date at 6:30. Comets always appear dimmer than their magnitude suggests because they are extended objects, not points like stars. Also, comet magnitudes can be unpredictable. Created using Cartes du Ciel (Sky Charts). I’ve reversed the colors from previous printings of this image. Reprinted from my article in the Stellar Sentinel, the newsletter for the Grand Traverse Astronomical Society.
12/01/2021 – Ephemeris – Let’s search for the naked-eye planets and a comet for this week
This is Bob Moler with Ephemeris for Wednesday, December 1st. Today the Sun will be up for 9 hours and 3 minutes, setting at 5:03, and it will rise tomorrow at 8:01. The Moon, 3 days before new, will rise at 5:45 tomorrow morning.
Let’s search for the naked-eye planets for this week. Venus will be visible in the southwestern evening twilight by 5:30 tonight. It’s a crescent in telescopes. It is moving closer to us, and now appears a bit larger than Jupiter in telescopes. Venus will set at 7:47 pm. By 5:45 pm, both Jupiter and Saturn should be able to be spotted in the southern sky. Saturn will be dimmer, and to its right. It will set first at 9:30 pm, with Jupiter following at 10:56 pm. A new comet named Leonard can be spotted with binoculars about 14 degrees above the bright star Arcturus in the east before 6:30 or 7am tomorrow morning. The spread of your fingers at arm’s length is about 15 degrees. The comet will move lower each morning.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location. That also applies to the times in the addendum below.
Addendum

The evening planets Venus, Saturn and Jupiter at 5:45 pm this evening, December 1, 2021. Created using Stellarium.

Comet Leonard, designation C/2021 A1, Finder chart looking East at 6:30 am. Arcturus is the brightest star in that direction. The handle of the Big Dipper is above and right of it. The comet is expected to be 7th magnitude, requiring binoculars or a telescope. It is expected to brighten to possibly be visible to the naked eye by the end of next week. No promises though. Created using Stellarium.

A closeup of the Moon and Mars at 7 am tomorrow morning, December 2, 2021. The star next to the Moon is Zubenelgenubi (south claw of the scorpion), in Libra. The Arabs, who named this star and most others, saw this star as part of Scorpius, to the left and yet to rise.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 7 pm, December 1, 2021. Apparent diameters: Venus, 39.41″, 27.9% illuminated; Saturn 15.99″, its rings 37.24″; Jupiter, 38.25″. The ” symbol means seconds of arc (1/3600th of a degree.) Jupiter’s other bright moons are behind the planet at 7 pm. Callisto will reappear on the eastern edge of Jupiter (Io’s side) at 9:13 pm. Created using Cartes du Ciel (Sky Charts).
11/24/2021 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Ephemeris for Wednesday, November 24th. Today the Sun will be up for 9 hours and 15 minutes, setting at 5:07, and it will rise tomorrow at 7:53. The Moon, 3 days before last quarter, will rise at 9:19 this evening.
Let’s search for the naked-eye planets for this week. Venus will be visible in the southwestern evening twilight by 5:30 tonight. It’s a fat crescent in telescopes. Venus will set at 7:49 pm. By 5:45 pm, both Jupiter and Saturn should be able to be spotted in the southern sky. Saturn will be dimmer, and to its right. It will set first at 9:54 pm, with Jupiter following at 11:19 pm. Saturn’s rings are a beautiful sight in a telescope of even modest power, but the planet will appear tiny. Jupiter, however, is still quite large, in binoculars it might seem that it only has two moons tonight, since Io and Europa are together on one side, and Ganymede and Callisto are together on the other side.
The astronomical event times given above and below are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum

The evening planets Venus, Saturn and Jupiter at 5:45 pm this evening, November 24, 2021. Created using Stellarium.

The Moon as it might appear in binoculars or small telescope, tomorrow morning, November 25, 2021. Created using Stellarium.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 7 pm, November 24, 2021. Apparent diameters: Venus, 35.32″, 33.4% illuminated; Saturn 16.15″, its rings 37.61″; Jupiter, 39.07″. The ” symbol means seconds of arc (1/3600th of a degree.) Click 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 November 24, 2021. The night ends on the left with sunrise on the 25th. Click on the image to enlarge it. Created using my LookingUp program.
11/17/2021 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Ephemeris for Wednesday, November 17th. Today the Sun will be up for 9 hours and 29 minutes, setting at 5:12, and it will rise tomorrow at 7:44. The Moon, 2 days before full, will set at 6:54 tomorrow morning.
Let’s search for the naked-eye planets for this week. Venus will be visible in the southwestern evening twilight by 5:30 tonight. It’s a fat crescent in telescopes. Venus will set at 7:48 pm. By 5:45 pm, both Jupiter and Saturn should be able to be spotted in the southern sky. Saturn will be dimmer, and to its right. It will set first at 10:19 pm, with Jupiter following at 11:42 pm. Saturn’s rings are a beautiful sight in a telescope of even modest power, but the planet will appear tiny. Jupiter, however, is still quite large, and its four biggest moons are spread out and might all be glimpsed in binoculars. In the morning sky, Mars is starting to make its appearance, rising at 6:33. Binoculars might be able to pick it out low in the east-southeast until 7:15 am.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum

The evening planets Venus, Saturn and Jupiter at 5:45 pm this evening, November 17, 2021. Created using Stellarium.

The Moon in binoculars or small telescope as it might appear tonight, November 17, 2021. Created using Stellarium.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 7 pm, November 17, 2021. Apparent diameters: Venus, 31.89″, 38.3% illuminated; Saturn 16.32″, its rings 38.01″; Jupiter, 39.95″. Mars in the morning is not shown, but is 3.70″ in diameter. The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
In the image above, Jupiter’s moon Europa is shown. Actually, before 7:03 pm, it will be hidden in Jupiter’s shadow. Watching it appear is kind of cool. Eclipses of Jupiter’s moons happen all the time. The information for the satellite events is published in Sky and Telescope Magazine. Also tonight, farther to the west, farther out than Ganymede, is the star 45 Capricorni, about the same brightness as the Jovian moons, and nearly in line with them. Don’t mistake it for one of the moons, especially before Europa appears.
11/10/2021 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Bob Moler with Ephemeris for Wednesday, November 10th. Today the Sun will be up for 9 hours and 46 minutes, setting at 5:19, and it will rise tomorrow at 7:34. The Moon, 1 day before first quarter, will set at 11:02 this evening.
Let’s search for the naked-eye planets for this week. Venus should be visible in the southwestern evening twilight by 5:40 tonight. It’s a fat crescent in telescopes. Venus will set at 7:46 pm. By 6 pm, Both Jupiter and Saturn should be able to be spotted in the southern sky. Saturn will be dimmer, and to its right. Saturn will be above and right of the Moon tonight. It will set first at 10:45 pm, with Jupiter following at 12:07 am. Saturn’s rings are a beautiful sight in a telescope of even modest power, but the planet will appear tiny. In the morning sky, Mercury now can only be spotted in a telescope, so its appearance in the morning sky is, for all practical purposes, over.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum

Evening planets and the Moon in twilight at 6 pm tonight, November 10, 2021. Click on the image to enlarge it. Created using Stellarium.

The crescent Moon as it might appear tonight in binoculars or small telescope. It appears here right side up as it would appear in the sky at 6 pm tonight, November 10, 2021. Created using Stellarium.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 7 pm, November 10, 2021. Apparent diameters: Venus, 28.99″, 42.7% illuminated; Saturn 16.50″, its rings 38.44″; Jupiter, 40.94″. The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
11/03/2021 – Ephemeris – Searching for the naked-eye planets for this week
This is Ephemeris for Wednesday, November 3rd. The Sun will rise at 8:23. It’ll be up for 10 hours and 4 minutes, setting at 6:28. The Moon, 1 day before new, will rise at 7:56 tomorrow morning.
Let’s search for the naked-eye planets for this week. Venus should be visible in the southwestern evening twilight by 6:50 tonight. It’s a fat crescent in telescopes. Venus will set at 8:44 pm. By 7 pm, Jupiter should be able to be spotted in the south-southeastern sky. Saturn will be dimmer, and to its right. They will set after midnight in the southwest, with Saturn setting first at 12:11 am, and Jupiter following at 1:32. Saturn’s rings are a beautiful sight in a telescope of even modest power, but the planet will appear tiny. In the morning sky, Mercury will be harder to spot than it was last week. It will be visible and low in the east-southeast from 7:30 to 8 am. All four of Jupiter’s brightest moons will be visible in binoculars early in the evening tonight.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.
Addendum

Venus will appear low in the south-southwest by 6:50 pm tonight, November 3, 2021. Created using Stellarium.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 9 pm, November 3, 2021. Apparent diameters: Venus at 7 pm, 26.54″, 46.7% illuminated; Saturn 16.69″, its rings 38.88″; Jupiter, 41.77″. Mercury at 7:30 am on the 4th and not plotted, 5.49″, 86.4% illuminated. The Jovian moon Io will begin transiting the face of the planet at 11:14 pm. Its shadow will start to cross at 12:32 am. The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
10/27/2021 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Bob Moler with Ephemeris for Wednesday, October 27th. Today the Sun will be up for 10 hours and 23 minutes, setting at 6:38, and it will rise tomorrow at 8:15. The Moon, 1 day before last quarter, will rise at 11:27 this evening.
Let’s search for the naked-eye planets for this week. Venus should be visible in the southwestern evening twilight by 7 tonight. It will set at 8:43 pm. By 7:15 pm, Jupiter will be spotted in the south-southeastern sky. Jupiter should be easy to spot at that hour. Saturn will be dimmer, and to its right. They will be visible for a while after midnight in the southwest, with Saturn setting first at 12:37 am, and Jupiter following at 1:57. Saturn’s rings are a beautiful sight in a telescope of even modest power, but the planet will appear tiny. In the morning sky, Mercury will be visible and low in the east-southeast for most of the 7 am hour. All four of Jupiter’s brightest moons will be visible in binoculars early in the evening tonight.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.
Addendum

Jupiter and Saturn in evening twilight at 7:15 pm tonight, October 27, 2021. Created using Stellarium.

The Moon as it might appear in binoculars or a small telescope tomorrow morning, October 28, 2021. Created using Stellarium.

Mercury in morning twilight finder for 7:30 am tomorrow, October 28, 2021. Created using Stellarium.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 9 pm, October 27, 2021. Apparent diameters: Venus at 7 pm, 24.19″, 50.8% illuminated; Saturn 16.92″, its rings 39.41″; Jupiter, 42.87″. Mercury at 7:30 am on the 28th and not plotted, 6.47″, 64.9% illuminated. The Jovian moon Io will begin transiting the face of the planet at 9:20 pm. Its shadow will start to cross at 10:37 pm. Io’s transit will end at 11:37 pm. The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
10/20/2021 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Bob Moler with Ephemeris for Wednesday, October 20th. Today the Sun will be up for 10 hours and 44 minutes, setting at 6:49, and it will rise tomorrow at 8:06. The Moon, is full today, the Hunter’s Moon, and will rise at 7:07 this evening.
Let’s search for the naked-eye planets for this week. Venus should be visible in the southwestern evening twilight by 7:10 tonight. It will set at 8:44 pm. By 7:30 pm, Jupiter will be spotted in the south-southeastern sky. Jupiter should be easy to spot at that hour. Saturn will be dimmer, and to its right. They will be visible for a while after midnight in the southwest, with Saturn setting first at 1:04 am, and Jupiter following at 2:24. Saturn’s rings are a beautiful sight in a telescope of even modest power, but the planet will appear tiny. In the morning sky, Mercury will be visible and low in the east-southeast by 7:15 am. It will reach its greatest separation from the Sun in six days.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT-4 hours). They may be different for your location.
Addendum

Venus seen in twilight at 7:10 pm, about 20 minutes after sunset tonight, October 20, 2021. Created using Stellarium.

Jupiter, Saturn and the Moon at 7:30, about 40 minutes after sunset tonight, October 20, 2021. Created using Stellarium.

Mercury and the star Arcturus in the morning twilight at 7:15 am, about 50 minutes before sunrise tomorrow morning, October 21, 2021. Don’t confuse the two. Click on the image to enlarge it. Created using Stellarium.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 8 pm, October 20, 2021. Apparent diameters: Venus, 22.70″, 53.7% illuminated; Saturn 17.08″, its rings 39.80″; Jupiter, 43.68″. Mercury at 7:15 am on the 21st and not plotted, 7.68″, 38.1% illuminated. The two Jovian moons transiting the face of the planet are usually not visible, though their shadows can be spotted. The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
10/13/2021 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Ephemeris for Wednesday, October 13th. Today the Sun will be up for 11 hours and 5 minutes, setting at 7:01, and it will rise tomorrow at 7:57. The Moon, 1 day past first quarter, will set at 1:00 tomorrow morning.
Let’s search for the naked-eye planets for this week. Venus should be visible in the southwestern evening twilight by 7:20 tonight. It will set at 8:37 pm. By 7:45 pm, Jupiter will be spotted in the south-southeastern sky. The Jupiter should be easy to spot at that hour. Saturn will be dimmer, and to its right. It will be above and left of the Moon tonight. They will be visible for a while after midnight in the southwest, with Saturn setting first at 1:31 am, and Jupiter following at 2:52. Saturn’s rings are a beautiful sight in a telescope of even modest power, but the planet will appear tiny. Jupiter’s 4 brightest moons are spread out, two on each side of the planet tonight. They might all be visible in binoculars.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT-4 hours). They may be different for your location.
Addendum

Venus seen in twilight at 7:20 pm, about 20 minutes after sunset on October 13, 2021. Created using Stellarium.

Jupiter, Saturn and the Moon at 7:45, about 45 minutes after sunset in this view to the south-southeast. Click on the image to enlarge it. Created using Stellarium.

The slight gibbous Moon as it might appear tonight in binoculars or small telescope. It appears here right side up as it would appear in the sky at 9 pm. Created using Stellarium.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 9 pm, October 13, 2021. Apparent diameters: Venus, 21.15″, 56.8% illuminated; Saturn 17.29″, its rings 40.27″; Jupiter, 44.63″. 9 pm is also the best time to find the Great Red Spot on Jupiter’s face. Io will be in transit of the face of Jupiter until 7:53 pm. After that, Io will be increasing its distance from the planet. The ” symbol means seconds of arc (1/3600th of a degree.) Click 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 October 13, 2021. The night ends on the left with sunrise on the 14th. It looks like Mercury will be far enough from the Sun next week to spot in the morning. Click on the image to enlarge it. Created using my LookingUp program.
10/06/2021 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Ephemeris for Wednesday, October 6th. Today the Sun will be up for 11 hours and 26 minutes, setting at 7:13, and it will rise tomorrow at 7:48. The Moon is new today, and won’t be visible.
Let’s search for the naked-eye planets for this week. Venus should be visible in the southwestern evening twilight by 7:45 tonight. It will set at 8:52 pm. By 8 pm, Jupiter will be spotted in the south-southeastern sky. The Jupiter should be easy to spot at that hour. Saturn will be dimmer, but a bit higher and to its right. They will be visible into the morning hours, with Saturn setting first at 1:58 am, and Jupiter following at 3:20. Saturn’s rings can be seen in a spotting scope of about 20 power magnification. Though at that power the rings won’t appear separated from the planet, so Saturn will look like an elliptical disk. Jupiter’s 4 brightest moons are spread out, three on one side, and one on the other. They might all be visible in binoculars tonight.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT-4 hours). They may be different for your location.
Addendum

Jupiter and Saturn at 8 pm, about 45 minutes after sunset tonight, October 6, 2021. Created using Stellarium.

Telescopic views of the bright planets (north up) as they would be seen in a small telescope, with the same magnification, this evening at 8 pm, October 6, 2021. Apparent diameters: Venus, 19.81″, 59.8% illuminated; Saturn 17.48″, its rings 40.73″; Jupiter, 45.55″. The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).











