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03/17/2021 – Ephemeris – Let’s search for the naked-eye planets for this week
This is Ephemeris for St. Patrick’s Day, Wednesday, March 17th. Today the Sun will be up for 12 hours and one minute, setting at 7:51, and it will rise tomorrow at 7:49. The Moon, halfway from new to first quarter, will set at 12:18 tomorrow morning.
Let’s search for the naked-eye planets for this week. Unfortunately the only one you’ll find in the evening is Mars. It can be found high in the west-southwest at 9 pm tonight, above a line between the Pleiades star cluster on its lower right and the letter V of stars that is the face of Taurus the bull on its lower left. The Pleiades will be above tonight’s waxing crescent Moon. Mars will set at 2:07 am.
Right now the other four naked eye planets are just west of the Sun in the Morning sky. But only Saturn and Jupiter are at a far enough angle from the Sun to be just be glimpsed in the morning sky. Saturn will rise at 6 am, with Jupiter a half hour later. By 7 am they will be low in the southeast.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mars finder animation for 9 pm, or about 70 minutes after sunset, tonight March 17, 2021. Created using Stellarium and GIMP.
The Moon as it might appear tonight, March 17, 2021, in binoculars or a small telescope. Created using Stellarium.
Jupiter and Saturn tomorrow morning at 7 am, March 18, 2021. Created by using Stellarium.
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on March 17, 2021. The night ends on the left with sunrise on the 18th. Venus is too close and south of the Sun to be plotted. Click on the image to enlarge. Created using my LookingUp program.
Venus in the Solar and Heliospheric Observatory (SOHO) LASCO C3 image. It will pass south and behind the Sun on the 26th and officially enter the evening sky.
03/10/2021 – Ephemeris – Searching for the naked-eye planets for this week
This is Ephemeris for Wednesday, March 10th. Today the Sun will be up for 11 hours and 39 minutes, setting at 6:42, and it will rise tomorrow at 7:01. The Moon, 3 days before new, will rise at 6:43 tomorrow morning.
Let’s search for the naked-eye planets for this week. Unfortunately the only one you’ll find in the evening is Mars. It can be found high in the west-southwest at 8 pm tonight, between the Pleiades star cluster on its right and the letter V of stars that is the face of Taurus the bull on its left. Mars will set at 1:13 am. Right now the other four naked eye planets are just west of the Sun in the Morning sky. But only Saturn is at a far enough angle to be just be glimpsed in the morning sky. It will rise at 5:27, about an hour and a half before sunrise in the east-southeast. By 6 am it will have risen and moved to the southeast. Even Jupiter might be spotted lower and left of Saturn, especially if you’re looking across the Lake Huron horizon.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mars finder chart for tonight March 10, 2021 at 8 pm. Click on the image to enlarge. Created using Stellarium.
The morning planets at 6 am, Thursday, March 11, 2021. Created using Stellarium.
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on March 10, 2021. The night ends on the left with sunrise on the 11th. The planet traffic jam in the morning is starting to break up. Saturn and possibly Jupiter can be spotted before sunrise now. Click on the image to enlarge. Created using my LookingUp program.
01/27/2021 – Ephemeris – Let’s have a lookout for the naked-eye planets for this week
This is Ephemeris for Wednesday, January 27th. Today the Sun will be up for 9 hours and 37 minutes, setting at 5:44, and it will rise tomorrow at 8:05. The Moon, 1 day before full, will set at 8:23 tomorrow morning.
Let’s have a lookout for the naked-eye planets for this week. Mercury will be low in the west-southwestern sky around 6:15 pm or about a half hour after sunset. It will set at 7:18 pm. Saturn and Jupiter are too close to the direction of the Sun to be seen. Saturn has passed into the morning sky, while Jupiter will pass behind the Sun tomorrow. Neither of these planets are visible. It will be a month or more before even Saturn will be visible in the morning twilight. Mars can be found quite high in the south at 7 pm. It will actually be due south at 6:43 tonight. Mars is increasing its speed eastward through the constellation of Aries the ram and will set at 1:52 am. Venus will be hard to spot in the morning twilight after it rises at 7:26 am tomorrow.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mercury in evening twilight at 6:15 pm tonight January 27, 2021. Created using Stellarium.
Mars and neighboring constellations for 7 pm tonight, January 27, 2021. Created using Stellarium.
The Moon as it might be seen in binoculars or low power telescope tonight at 7 pm, January 27, 2021. Created using Stellarium.
Venus in morning twilight over a water horizon. Around here that would be Lake Huron shortly after 7:30 am tomorrow January 28, 2021. Created using Stellarium.
The graphic illustrating the planets as seen in a telescope is on hiatus until Jupiter and Saturn clear the Sun in the morning sky in a couple of months. Mars appears too small to show any detail in a small telescope.
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on January 27, 2021. The night ends on the left with sunrise on the 28th. I’m afraid that the labels for Jupiter and the Sun overlap, since the planets and Sun are very close. Click on the image to enlarge. Created using my LookingUp program.
01/13/2021 – Ephemeris – Let’s take a look for the naked-eye planets for this week
This is Bob Moler with Ephemeris for Wednesday, January 13th. Today the Sun will be up for 9 hours and 8 minutes, setting at 5:26, and it will rise tomorrow at 8:16. The Moon is new today, and won’t be visible.
Let’s take a look for the naked-eye planets for this week. Mercury has joined Jupiter and Saturn extremely low in the southwestern sky. I’m afraid Saturn will be lost in the twilight, but Jupiter, with Mercury above it might be visible. They are both extremely low in the southwestern sky around 6 pm. Jupiter will set at 6:20 pm with Mercury following 20 minutes later. Quite high in the south at 7 pm Mars can be found. It will be actually due south on the meridian at 7:10 pm tonight. The meridian is an imaginary line that runs from the north compass point on one’s horizon, through the zenith to the south compass point. Mars is beginning to increase its speed eastward and will set at 2:09 am. Venus, our brilliant morning star will rise at 7:15 am in the east-southeast.
Addendum
Jupiter and Mercury in evening twilight st 6 pm, about a half hour after sunset over the Lake Michigan horizon. Saturn, though present can’t compete with the bright twilight. The less than one day old moon is setting. Created using Stellarium.
Mars finder animation for 8 pm tonight, January 13, 2021 (about 2 1/2 hours after sunset. Looking southward. Created using Stellarium and GIMP.
Venus in the morning twilight at 7:45 am tomorrow morning January 14, 2021 (about 1/2 hour before sunrise). Created using Stellarium.
The graphic that shows the planets as seen in small telescopes has been discontinued because Jupiter and Saturn are too close to the horizon and Venus and Mars are too small (less than 10 seconds of arc in diameter). It will be resumed in a couple of months when Jupiter and Saturn become visible in the morning sky.
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on January 13, 2021. The night ends on the left with sunrise on the 14th. 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.
01/06/2021 – Ephemeris – Let’s take our first look at the naked-eye planets for 2021
This is Bob Moler with Ephemeris for Wednesday, January 6th. Today the Sun will be up for 8 hours and 58 minutes, setting at 5:18, and it will rise tomorrow at 8:19. The Moon, at last quarter today, will rise at 1:57 tomorrow morning.
Let’s take our first look at the naked-eye planets for 2021. Jupiter and Saturn are both extremely 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 two degrees or four moon widths. They crossed paths for us 16 nights ago. They can still be seen in the same binocular field. Saturn will set first tonight at 6:33 pm with Jupiter following nine minutes later. Quite high in the southeast at that hour will be Mars, still in Pisces. It will pass due south at 7:25 tonight. Mars’ distance is increasing to 88 million miles (141 million km) away. It will set at 2:19 tomorrow morning. Venus, our brilliant morning star will rise at 7:03 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 just above the distant trees at 6 pm January 6, 2021. We might lose them in twilight next week. We’ll have to move to a Lake Michigan horizon to try to spot them. Created using Stellarium.
Mars in the evening sky at 8 pm January 6, 2021 looking southward. Mars is on the boarder between Pisces on the right and Aries above and left. Also seen on the left is the tiny dipper shape of the Pleiades or Seven Sisters star cluster and farther to the left the letter V of stars that is the face of Taurus the bull with the bright star Aldebaran. Created using Stellarium.
The waning crescent Moon at around 7 am January 7, 2021 as it might be seen in binoculars or a small telescope. Created using Stellarium.
Venus seen low on the southeastern horizon at 7:30 in the morning on January 7, 2021. Created using Stellarium.
The planets Jupiter and Saturn as they might be seen in a small telescope at 6 pm, January 6, 2021. These planets are seen in twilight so Saturn’s moons will be invisible, and Jupiter’s moons nearly so. Mars is not shown because its apparent size is less than 10″ (seconds of arc in diameter), and Venus, nearly so. Apparent diameters: Jupiter, 32.73″; Saturn, 15.20″, rings, 35.42″; Mars, 9.82″, and Venus, 10.55″ 95% full.
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on January 6, 2021. The night ends on the left with sunrise on the 7th. I’m afraid that the labels for Jupiter and Saturn overlap, since the planets are very close. Click on the image to enlarge. Created using my LookingUp program.
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.
Bob Moler's Ephemeris Blog 