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12/30/2020 – Ephemeris – Let’s take our last look at the naked-eye planets for this year
This is Bob Moler with Ephemeris for Wednesday, December 30th. Today the Sun will be up for 8 hours and 51 minutes, setting at 5:11, and it will rise tomorrow at 8:20. The Moon, 1 day past full, will rise at 5:40 this evening.
Let’s take our last look at the naked-eye planets for this year. Jupiter and Saturn are both low in the southwestern sky around 6 pm. Jupiter is the very bright one. Below and right of it is the dimmer Saturn it by a degree or two moon widths. They crossed paths for us nine nights ago. They can still be seen in the same binocular field. Saturn will set first tonight at 6:57 pm with Jupiter following four minutes later. Quite high in the southeast will be Mars, still in Pisces. Mars’ distance is increasing to 82 million miles (132 million km) away. It will set at 2:29 tomorrow morning. Brilliant Venus will rise at 6:49 am in the east-southeast as it seems to retreat slowly toward the Sun, but actually it’s heading way around behind the Sun.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Saturn low on the southwestern horizon at 6 pm. Created using Stellarium.
Mars with the stars of Taurus the Bull including Aldebaran with the “V” of stars that are the Hyades that mark the bull’s face and the Pleiades. Seen at 8 pm, December 30, 2020. Created using Stellarium.
The Moon as it might be seen tonight at 8 pm, December 30, 2020. Created using Stellarium.
Venus in the southeast at 7:30 am. Created using Stellarium.
The planets as seen in a telescope (north up) with the same magnification for the night of December 30/31, 2020. Times of the display are: Jupiter and Saturn, 6 pm; Mars, 8 pm; Venus, 7:30 am. Apparent diameters: Jupiter, 32.92″; Saturn, 15.26″, rings, 35.54″; Mars, 10.52″, and Venus 10.71″. Mars also displays an enlargement showing surface detail. Mars was closest to the Earth this go-a-round on October 6. The ” symbol means seconds of arc (1/3600th of a degree.) Planets whose diameters drop below 10″, or are too close to the direction of the Sun to observe will not be shown. Created using Cartes du Ciel (Sky Charts).
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on December 30, 2020. The night ends on the left with sunrise on the 31st. I’m afraid that the labels for Jupiter and Saturn will overlap, since the planets are very close. Click on the image to enlarge. Created using my LookingUp program.
12/25/2020 – Ephemeris – Did the “Star” of Bethlehem appear in 3 BC and again in 2 BC?
Merry Christmas, this is Bob Moler with Ephemeris for Christmas Day, Friday, December 25th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:07, and it will rise tomorrow at 8:19. The Moon, halfway from first quarter to full, will set at 4:53 tomorrow morning.
Many writers of the 2nd and 3rd centuries AD place Jesus’ birth around 2 BC, which had to be before Herod the Great’s death, which I suggest was in 1 BC marked by to a total lunar eclipse. In 3 and again in 2 BC there were star-like conjunctions or apparent joinings of the planets Jupiter and Venus against the backdrop of the constellation of Leo the Lion. A lion is related to Judah, son of Jacob by a blessing the latter gave his 12 sons in Genesis. The first conjunction occurred in August of 3 BC in the morning sky. In June the next year the two planets got together again, this time in the evening sky, just after Jesus would have been born in the lambing season of spring.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Here is an animation created using Stellarium of Jupiter and Venus, the brighter of the two seeming to coalesce on August 12, 3 BC in the early morning twilight. The ghostly image popping up in the second frame is the thin crescent Moon showing earth shine. Created using Stellarium and GIMP.
On June 16th 2 BC, this time in the evening, Venus and Jupiter seem to coalesce as one, at least to the naked eye. Regulus (The Little King star) is the brightest star in Leo the lion. To the upper right of it is the Sickle, the front part of the lion and his head and mane. Created using Stellarium and GIMP.
12/24/2020 – Ephemeris – Was the Star of Bethlehem a triple conjunction of Jupiter and Saturn in 7 BC?
This is Bob Moler with Ephemeris for Christmas Eve, Thursday, December 24th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:07, and it will rise tomorrow at 8:18. The Moon, 3 days past first quarter, will set at 3:50 tomorrow morning.
For many years the most popular theory for the origin of the Star of Bethlehem was a triple conjunction of Jupiter and Saturn in 7 BC. This is because, due to Earth’s motion, other planets from our view point seem to reverse course when we pass them or are being passed in the circular racetrack of the solar system. When Jupiter and Saturn approach each other just before they go retrograde or reverse course they have a chance to pass each other, backup and pass again, then going forward to pass a third time. Jupiter and Saturn did that last in 1981, so it’s a reasonably rare occurrence, especially when it happens in front of the constellation Pisces which was supposedly related to the Jews.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Saturn pass each other three times from May to December in 7 BC against the constellation of Pisces. Reload the page to replay the animation. Created using Cartes du Ciel (Sky Charts) and GIMP.
Retrograde motion illustrated using Mars in 2018. Created using my LookingUp program.
12/23/2020 – Ephemeris – Let’s look for the naked-eye planets for this Christmas week
This is Ephemeris for Wednesday, December 23rd. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:06, and it will rise tomorrow at 8:18. The Moon, 2 days past first quarter, will set at 2:49 tomorrow morning.
Let’s look for the naked-eye planets for this week. Jupiter and Saturn are both low in the southwestern sky around 6 pm. Jupiter is the very bright one. Below and right of it is the dimmer Saturn it by a quarter of a degree or half a moon width. They crossed paths for us two nights ago, in 20 years, though not as close. They can still be seen in the same low power telescope field. Saturn will now set first tonight at 7:20 pm with Jupiter following a minute later. Quite high in the southeast and above the 9 day old Moon at that hour will be Mars, still in Pisces. Mars’ distance is increasing to 76 million miles (123 million km) away. It will set at 2:41 tomorrow morning. Brilliant Venus will rise at 6:33 am in the east-southeast as it seems to retreat slowly toward the Sun, but actually it’s heading way around behind the Sun.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Saturn in twilight at 6 pm or a bit less than an hour after sunset tonight December 23, 2020. Created using Stellarium.
Mars will be seen above the Moon tonight. This is the appearance of both at 6 pm, tonight, December 23, 2020. Created using Stellarium.
The gibbous Moon as it might be seen in binoculars this evening at 6 pm December 23, 2020. Created using Stellarium.
Venus low in the southeast at 7:30 am December 24, 2020. The morning sky is not as friendly to morning planets as it was earlier in autumn. Created using Stellarium.
The planets as seen in a telescope (north up) with the same magnification for the night of December 23/24, 2020. Times of the display are: Jupiter, Saturn, and Mars, 6 pm; Venus, 7:30 am. Apparent diameters: Jupiter, 33.18″; Saturn, 15.32″, rings, 35.70″; Mars, 11.32″, and Venus 10.89″. Mars also displays an enlargement showing surface detail. Mars was closest to the Earth this go-a-round on October 6. The ” symbol means seconds of arc (1/3600th of a degree.) I will no longer show planets whose diameters drop below 10″, or are too close to the direction of the Sun to observe. Created using Cartes du Ciel (Sky Charts).
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on December 23, 2020. The night ends on the left with sunrise on the 24th. I’m afraid that the labels for Jupiter and Saturn will overlap, since the planets are very close. Click on the image to enlarge. Created using my LookingUp program.
12/21/2020 – Ephemeris – Jupiter and Saturn will appear super close tonight
This is Ephemeris for Monday, December 21st. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:05, and it will rise tomorrow at 8:17. The Moon, at first quarter today, will set at 12:45 tomorrow morning.
Today we begin winter and the conjunction or extremely close grouping of Jupiter and Saturn low in the southwestern sky from about 6 to 7 pm. At that time they will be a fifth of the diameter of the Moon apart. Depending on sky conditions, Saturn may not even be visible, lost in twilight or in the glare of Jupiter which is 11 times brighter. A pair of binoculars, or a low power telescope will confirm their appearance, with Saturn to the upper right of Jupiter. Conjunctions of Jupiter and Saturn occur about every 20 years, the last in 2000. The conjunction before that was a triple conjunction like has been proposed for the Star of Bethlehem occurring during the first 11 months of 1981. The next conjunction will be on November 5th, of 2040.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Saturn as they would appear in a low power telescope field tonight December 21, 2020, between 6 and 7 pm. Created using Cartes du Ciel (Sky Charts)
The Earth-Jupiter-Saturn conjunction line of sight. Created using my LookingUp for Windows program.
12/16/2020 – Ephemeris – Let’s look for the naked-eye planets for this week
This is Bob Moler with Ephemeris for Wednesday, December 16th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:03, and it will rise tomorrow at 8:14. The Moon, 2 days past new, will set at 7:09 this evening.
Let’s look for the naked-eye planets for this week. Jupiter and Saturn are both low in the southwestern sky from 6 to 7 pm. Jupiter is the very bright one. Above and left it by half a degree or one moon width will be dimmer Saturn. Below them tonight will be the thin crescent Moon. They will cross paths for us on the evening of December 21st and be seen in the same low power telescope field that evening. Jupiter will set first tonight at 7:40 pm with Saturn following four minutes later. Quite high in the southeast at that hour will be Mars, still in Pisces. Mars’ distance is increasing to 71 million miles (114 million kilometers) away. It will set at 2:55 tomorrow morning. Brilliant Venus will rise at 6:16 am in the east-southeast as it seems to retreat slowly toward the Sun, but actually it’s heading way around behind the Sun.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Saturn with Moon at 6 pm tonight December 16, 2020. Created using Stellarium.
Evening planet panorama showing Mars, Jupiter, Saturn and the Moon setting at 6:30 pm December 16, 2020. Click on the image to enlarge. Created using Stellarium.
Venus low in the southeast at 7 am December17, 2020. Venus is all by its lonesome in the morning sky. No need for a panorama, so we’re zoomed in a bit. The morning sky has is not as friendly to morning planets as it was earlier in autumn season as we embark into winter next week. Created using Stellarium.
The planets as seen in a telescope (north up) with the same magnification for the night of December 16/17, 2020. Times of the display are: Jupiter and Saturn, 6 pm and Mars, 8 pm; Venus, 7 am. Apparent diameters: Jupiter, 33.49″; Saturn, 15.41″, rings, 35.90″; Mars, 12.20″, and Venus, 11.10″. Europa is transiting Jupiter and will be generally invisible. Mars also displays an enlargement showing surface detail. Mars was closest to the Earth this go-a-round on October 6. The ” symbol means seconds of arc (1/3600th of a degree.) Created using Cartes du Ciel (Sky Charts).
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on December 16, 2020. The night ends on the left with sunrise on the 17th. I’m afraid that the labels for Jupiter and Saturn will overlap, since the planets are getting very close. Click on the image to enlarge. Created using my LookingUp program.
12/09/2020 – Ephemeris – A look at the naked-eye planets for this week
This is Ephemeris for Wednesday, December 9th. Today the Sun will be up for 8 hours and 53 minutes, setting at 5:02, the earliest sunset, and it will rise tomorrow at 8:09. The Moon, 2 days past last quarter, will rise at 2:55 tomorrow morning.
Let’s look for the naked-eye planets for this week. Jupiter and Saturn are both low in the southwestern sky from 6 to 7 pm. Jupiter is the very bright one. Above and left it by one and a half degrees or three moon widths will be dimmer Saturn. They are slowly closing, so they will cross paths for us on the evening of December 21st and be seen in the same low power telescope field that evening. Jupiter will set first tonight at 8 pm with Saturn following at 8:08. Quite high in the southeast at that hour will be Mars, still in Pisces. Mars’ distance is increasing to 65.3 million miles (105.2 million km) away. It will set at 3:10 tomorrow morning. Brilliant Venus will rise at 5:58 am in the east-southeast as it retreats slowly towards the Sun, but actually it’s heading around behind the Sun.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The evening planets seen at 6:30 pm or about an hour and a half after sunset December 9, 2020. Animation showing non-annotated sky and then with annotations. Click on the image to enlarge. Created using Stellarium and GIMP.
Venus and the waning crescent Moon at 6:30 am on December 10, 2020. Created using Stellarium.
The waning crescent Moon as it might appear in binoculars or a small telescope at 6:30 am December 10, 2020. Created using Stellarium.
The planets as seen in a telescope (north up) with the same magnification for the night of December 9/10, 2020. Times of the display are: Jupiter, Saturn and Mars, 6:30 pm; Venus, 6:30 am. Apparent diameters: Jupiter, 33.85″; Saturn, 15.51″, rings, 36.13″; Mars, 13.18″, and Venus 11.32″. Io is transiting Jupiter and will be generally invisible. Mars also displays an enlargement showing surface detail. Mars was closest to the Earth this go-a-round on October 6. The ” symbol means seconds of arc (1/3600th of a degree). Created using Cartes du Ciel (Sky Charts).
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on December 9, 2020. The night ends on the left with sunrise on the 10th. I’m afraid that the labels for Jupiter and Saturn will overlap, since the planets are getting very close. Click on the image to enlarge. Created using my LookingUp program.
12/02/2020 – Ephemeris – A look at the naked-eye planets for this week
This is Ephemeris for Wednesday, December 2nd. Today the Sun will be up for 9 hours and 1 minute, setting at 5:03, and it will rise tomorrow at 8:02. The Moon, 2 days past full, will rise at 6:51 this evening.
Let’s look for the naked-eye planets for this week. Jupiter and Saturn are both low in the southwestern sky from 7 to 8 pm. Jupiter is the very bright one. Above and left it by 2 degrees or 4 moon widths will be dimmer Saturn. They are slowly closing, so they will cross paths on the evening of December 21st and be seen in the same telescope field that evening. Jupiter will set first tonight at 8:20 with Saturn following at 8:32. Quite high in the southeast at that hour will be Mars, still in Pisces. Mars’ distance is increasing to 60.2 million miles (97.0 million km) away. Mars will set at 3:27 tomorrow morning. Brilliant Venus will rise at 5:40 am in the east-southeast as it retreats slowly towards the Sun, but actually it’s heading around behind the Sun.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The evening planets with the Mon rising at 7 pm tonight December 2, 2020. Click on the image to enlarge. Created using Stellarium.
The Moon as it might be seen tonight at 9 pm, December 2, 2020. Created using Stellarium.
The planets as seen in a telescope (north up) with the same magnification for the night of November 25/26, 2020. Times of the display are: Jupiter, Saturn and Mars, 7 pm; Venus, 6:30 am. Apparent diameters: Jupiter, 34.28″; Saturn, 15.63″, rings, 36.41″; Mars, 14.27″; and Venus, 11.57″. Mars also displays an enlargement showing surface detail. Mars was closest to the Earth this go-a-round on October 6. The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge. Created using Cartes du Ciel (Sky Charts).
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on December 2, 2020. The night ends on the left with sunrise on the 3rd. I’m afraid that the labels for Jupiter and Saturn will overlap, since the planets are getting very close. Click on the image to enlarge. Created using my LookingUp program.
11/26/2020 – Ephemeris – A look at Saturn (planet and god) in mythology
This is Ephemeris for Thanksgiving Day, Thursday, November 26th. Today the Sun will be up for 9 hours and 11 minutes, setting at 5:05, and it will rise tomorrow at 7:55. The Moon, 4 days before full, will set at 4:59 tomorrow morning.
Over the next 25 days Jupiter and Saturn will draw together to be in conjunction. And like I said Tuesday, I don’t know what that means astrologically, since I don’t believe in that stuff. I find the universe quite indifferent to my fate or the fate of anything happening on the third rock. Saturn, which will seem to cross paths with Jupiter on the evening of December 21st, a few hours after winter starts is named after the Roman god of agriculture and periodic renewal among others. He is depicted carrying a scythe, and even today we see him as the Grim Reaper, and at the end of the year as Father Time. The Saturn is the Roman counterpart of the Greek Cronus a Titan, the bringer of old age. It’s a fitting name for the slowest of the naked-eye planets, known from antiquity, taking almost 30 years to shuffle its way around the Sun.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Saturn and rings from the Cassini spacecraft, plus the aurora oval in ultraviolet. Credit: NASA/JPL/Space Science Institute
A statuette of Cronus (Saturn) shown holding a scythe and an hour glass. Source: https://respuestas.tips/quien-es-cronos-en-la-mitologia-griega/
11/25/2020 – Ephemeris – Let’s look for the naked-eye planets for this week
This is Ephemeris for Wednesday, November 25th. Today the Sun will be up for 9 hours and 12 minutes, setting at 5:06, and it will rise tomorrow at 7:54. The Moon, 4 days past first quarter, will set at 3:58 tomorrow morning.
Let’s look for the naked-eye planets for this week. Jupiter and Saturn are both low in the southwestern sky from 7 to 8 pm. Jupiter is the very bright one. Above and left will be dimmer Saturn. They are slowly closing, so they will cross paths on the evening of December 21st and be seen in the same telescope field that evening. Jupiter will set first tonight at 8:41 with Saturn following at 8:56. Off in the southeast at that hour will be Mars above the bright gibbous Moon tonight. Mars’ distance is increasing to 55.6 million miles (89.6 million kilometers) away. Mars will set at 3:47 tomorrow morning. Brilliant Venus will rise at 5:21 am in the east-southeast as it retreats slowly toward, but actually around the back of the Sun.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Evening planets and the Moon for 7 pm tonight November 25, 2020. Click on the image to enlarge. Created using Stellarium.
The gibbous Moon as it might be seen in binoculars this evening at 7 pm November 25, 2020. Created using Stellarium.
Venus and the morning constellations at 6:30 am tomorrow November 26, 2020. Created using Stellarium.
The planets as seen in a telescope (north up) with the same magnification for the night of November 25/26, 2020. Times of the display are: Jupiter and Saturn, 7 pm; Mars, 10 pm; Venus, 6:30 am. Apparent diameters: Jupiter, 34.76″; Saturn, 15.76″, rings, 36.72″; Mars, 15.45″, and Venus 11.85″. Mars also displays an enlargement showing surface detail. Mars was closest to the Earth this go-a-round on October 6. The ” symbol means seconds of arc (1/3600th of a degree.) Created using Cartes du Ciel (Sky Charts).
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on November 25, 2020. The night ends on the left with sunrise on the 26th. I’m afraid that the labels for Jupiter and Saturn will overlap, since the planets are getting very close. Click on the image to enlarge. Created using my LookingUp program.
Bob Moler's Ephemeris Blog 