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05/03/2023 – Ephemeris – Let’s find where the naked-eye planets have wandered off to this week
This is Ephemeris for Wednesday, May 3rd. Today the Sun will be up for 14 hours and 19 minutes, setting at 8:49, and it will rise tomorrow at 6:28. The Moon, 2 days before full, will set at 5:56 tomorrow morning.
Let’s find where the naked-eye planets have wandered off to this week. Venus is our blazing Evening Star, seen in the west all evening. It will set after midnight. The red planet Mars is in Gemini, below Pollux, left of Castor, the namesake stars of the twins. Mars is above and left of Venus by 24 degrees, or almost two and a half times the width of one’s fist held at arm’s length. Venus is closing the gap between them, but will never quite reach Mars while they are in the evening sky. The closest they will get is three and a half degrees or 7 moon diameters apart, before Venus pulls back toward the Sun faster than Mars will. Saturn, low in the southeast by 6 am, is emerging from morning twilight, rising at 4:07 am. Both Jupiter and Mercury are too close to the direction of the Sun to be seen.
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 and Mars among the setting winter stars tonight, at 10 pm, May 3rd, 2023. Click or tap on the image to enlarge it. Created using Stellarium, Libreoffice Draw and GIMP.
Moon 2 days before full, annotated for 10 pm, May 3, 2023. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Venus and Saturn (north up) as they would be seen in a small telescope, with the same magnification. Apparent diameters: Venus 17.43″ and is 65.2% illuminated; Saturn 16.39″, its rings 38.19″. Mars, too small to be represented here, is 5.30″ in diameter. 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 May 3, 2023. The night ends on the left with sunrise on the 4th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
04/26/2023 – Ephemeris – Let’s find where the naked-eye planets have wandered off to this week
This is Ephemeris for Wednesday, April 26th. Today the Sun will be up for 14 hours even, setting at 8:41, and it will rise tomorrow at 6:39. The Moon, 1 day before first quarter, will set at 3:28 tomorrow morning.
Let’s find where the naked-eye planets have wandered off to this week. Venus is our blazing Evening Star, seen in the west all evening. It will set after midnight. It’s in Gemini, below the namesake stars of the twins Castor on the right and Pollux on the left. Pollux is a bit below and to the right of the Moon tonight. Mars is above and left of Venus. Venus is closing the gap between them, but will never quite reach Mars while they are in the evening sky. The closest they will get is three and a half degrees or 7 moon diameters apart, before Venus pulls back toward the Sun faster than Mars. They won’t cross paths until February of next year. Saturn is emerging from morning twilight, rising at 4:33 am in the east-southeast. Both Jupiter and Mercury are too close to the direction of the Sun to be seen.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT –4 hours). They may be different for your location.
Addendum
Evening planets and stars looking westward at 10 pm tonight, April 26, 2023. Click or tap on the image to enlarge it. Created using Stellarium and GIMP.
The Moon, one day before first quarter tonight, April 26, 2023, with prominent features labeled. Created using Stellarium, GIMP and LibreOffice Draw.
Saturn, low in the east-southeast at 5:30 am, April 27, 2023. Created using Stellarium.
Telescopic Venus and Saturn (north up) as they would be seen in a small telescope, with the same magnification. Apparent diameters: Venus 16.51″ and is 68.1% illuminated; Saturn 16.23″, its rings 37.80″. Mars is too small to be represented here. It is 5.5″ in diameter. 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 April 26, 2023. The night ends on the left with sunrise on the 27th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
04/25/2023 – Ephemeris – The Moon is passing Mars today
This is Bob Moler with Ephemeris for Tuesday, April 25th. Today the Sun will be up for 13 hours and 57 minutes, setting at 8:40, and it will rise tomorrow at 6:40. The Moon, 2 days before first quarter, will set at 2:50 tomorrow morning.
Tonight, the Moon and the planet Mars will appear close to each other. The Red Planet will appear just below and left of the waxing crescent Moon. Mars is a lot dimmer than it was last December. That’s because it is a lot farther away than it was back then, 157 versus 51 million miles (253 versus 82 million kilometers). Mars is the planet with the greatest distance variation percentage over its synodic period, that is, from opposition to the next opposition. It also has the longest synodic period, at 26 months on average. That’s why opportunities to launch spacecraft only occur every 26 months. The least energy it takes to get to Mars occurs when a spacecraft is launched a few months before opposition, when Mars is at its closest, to arrive several months after opposition.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT –4 hours). They may be different for your location.
Addendum
The Moon and Mars as they should appear in the west tonight, April 25, 2023, at 10 pm. Created using Stellarium.
Illustration of the route Mars 2020 (Perseverance) took to arrive at the Red Planet, including several trajectory correction maneuvers (TCMs) to adjust its flight path. Credit NASA/JPL.
02/08/2023 – Ephemeris – Let’s find where the naked-eye planets have wandered off to this week
This is Bob Moler with Ephemeris for Wednesday, February 8th. Today the Sun will be up for 10 hours and 7 minutes, setting at 6:01, and it will rise tomorrow at 7:52. The Moon, 3 days past full, will rise at 9:02 this evening.
Let’s find where the naked-eye planets have wandered off to this week. Very early after sunset, Venus can be spotted low in the southwest by 6:30 pm. Mars, and Jupiter will be visible this evening by 7 pm. Mars will be above Orion in the southeast and is pulling away from the Pleiades. Jupiter will be in the southwest. Saturn is way below Venus now, so it’s gone until it reappears in the morning sky in a few months. It will make the crossing to the morning sky with its solar conjunction on the 16th. Jupiter will cross paths with Venus on March 1st. Mercury is now in the morning sky, but too close to the Sun to be visible.
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 naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on February 8, 2023. The night ends on the left with sunrise on the 9th. Click on the image to enlarge it. Created using my LookingUp app and GIMP.
02/01/2023 – Ephemeris – Let’s find where the naked-eye planets have wandered off to this week
This is Ephemeris for Wednesday, February 1st. Today the Sun will be up for 9 hours and 49 minutes, setting at 5:51, and it will rise tomorrow at 8:00. The Moon, halfway from first quarter to full, will set at 6:31 tomorrow morning.
Let’s find where the naked-eye planets have wandered off to this week. Very early after sunset. Venus can be spotted low in the southwest by 6:30 pm. Mars, and Jupiter will be visible this evening by 7 pm. Mars will be above Orion in the southeast and is pulling away from the Pleiades. Jupiter will be in the southwest. Saturn is way below Venus now, so it’s gone until it reappears in the morning sky in a few months. It will make the crossing to the morning sky with its solar conjunction on the 16th. Mercury is now in the morning sky. It has a few more days visibility around 7 am in the southeastern sky after reaching greatest western elongation from the Sun last Sunday.
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
Venus low in the west-southwestern twilight at 6:30 pm tonight, February 1, 2023. Created using Stellarium.
Evening planets at 7 pm tonight, February 1, 2023. The orange line is the ecliptic, which is the plane of the Earth’s orbit. The sun appears on that line throughout the year. Notice that all the other planets are very close to that line. That is an artifact of the accretion disk from which the planets formed some 4 1/2 billion years ago. The planets still maintain the nearly same plane for their existence to this day. Click on the image to enlarge it. Created using Stellarium.
The gibbous Moon tonight at 7:00 pm, labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
This is what Mercury might look like in the southeast around 7:20 tomorrow morning, February 2nd from Interlochen/Traverse City. At that time, it’ll be 5 degrees above a sea horizon, which is half the width of a fist held at arm’s length. Any trees of course will reduce it. Created using Stellarium.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on February 1, 2023. The night ends on the left with sunrise on the 2nd. Click on the image to enlarge it. Created using my LookingUp app and GIMP.
01/25/2023 – Ephemeris – Let’s see where the naked-eye planets have wandered off to this week
This is Bob Moler with Ephemeris for Wednesday, January 25th. Today the Sun will be up for 9 hours and 32 minutes, setting at 5:41, and it will rise tomorrow at 8:08. The Moon, 3 days before first quarter, will set at 10:42 this evening.
Let’s see where the naked-eye planets have wandered off to this week. Very early after sunset, Venus might be spotted very low in the southwest by a little past 6 pm. Mars, and Jupiter will be visible this evening, in the east to southwestern sky by 6:30 or 7 pm. Mars will be above Orion in the east-southeast and is pulling away from the Pleiades. Jupiter is brighter than Mars, and will be in the south-southwest, and tonight it’s directly above the crescent Moon. Saturn is below Venus now, so it’s pretty much gone until it reappears in the morning sky in a few months. Mercury is now in the morning sky, after it passed inferior conjunction with the Sun on the 7th, that is, it passed between the Earth and the Sun. It should be briefly visible before sunrise by month’s end.
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
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01/18/2023 – Ephemeris – Let’s see where the naked-eye planets have wandered off to this week
This is Ephemeris for Wednesday, January 18th. Today the Sun will be up for 9 hours and 17 minutes, setting at 5:32, and it will rise tomorrow at 8:14. The Moon, 3 days before new, will rise at 6:28 tomorrow morning.
Let’s see where the naked-eye planets have wandered off to this week. Very early after sunset, Venus might be spotted very low in the southwest by 6 pm. Mars, Jupiter and Saturn will be visible this evening, in the east to southwestern sky by 6:30 or 7 pm. Mars will be above Orion in the east-southeast and near the Pleiades. Jupiter is the brightest of the three and will be in the south-southwest., while dimmer Saturn will be very low in the southwest at that time. Saturn, the westernmost of these bright planets, will set around 7:42 this evening. It’s a bit above and left of Venus. Mercury is now in the morning sky, after it passed inferior conjunction with the Sun on the 7th, that is, it passed between the Earth and the Sun. It should be briefly visible before sunrise by month’s end.
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
Venus and Saturn low in the southwest at 6:15 pm tonight, January 18, 2023. Saturn will probably not be visible yet, but Venus should be plenty bright enough. Created using Stellarium.
All the evening planets before Venus sets are in this panorama looking southward from east to west at 7:15 tonight, January 18, 2023. I dropped lines from some of the dimmer constellations. Click on the image to enlarge it. Created using Stellarium.
Telescopic views of Saturn Jupiter and Mars (north up) as they would be seen in a small telescope, with the same magnification. The image of Mars doesn’t show it, but the white north polar cap will appear at the top or north limb of Mars. The planets are shown at 7 pm tonight, January 18, 2023. Apparent diameters: Venus 10.77″ and is 93.5% illuminated; Saturn 15.52″, its rings 36.16″; Jupiter 37.32″. Mars 12.25″. Mars’ distance is71.6 million miles (114.4 million kilometers). 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 January 18, 2023. The night ends on the left with sunrise on the 19th. Click on the image to enlarge it. Created using my LookingUp app and GIMP.
12/28/2022 – Ephemeris – Taking a look at the bright planets for the last week of the year
This is Ephemeris for Wednesday, December 28th. Today the Sun will be up for 8 hours and 49 minutes, setting at 5:09, and it will rise tomorrow at 8:19. The Moon, 1 day before first quarter, will set at 11:46 this evening.
Let’s see where the naked-eye planets have wandered off to this week. Mars, Jupiter and Saturn will be visible this evening, in the east to southwestern sky at 6:30 pm. Mars is in the east. Jupiter is the brightest of the three in the south, while dimmer Saturn is low in the southwest at that time. Mars is above Orion as it rises in the early evening. Saturn, the westernmost of the bright planets, will set around 8:52 this evening. Venus and Mercury are also in the evening sky, but too close to the setting Sun to be easily spotted. At 6 pm, both will be very low on the southwestern horizon, with Mercury just above Venus by three moon-widths. There are now no bright morning planets, though Mars won’t set until 6:32 am in the northwest.
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 naked eye Planets and Moon at 8 in the evening tonight, December 28, 2022. Created using Stellarium.
Waxing crescent Moon as it might appear in binoculars or low power telescope tonight, December 28, 2022. Created using Stellarium, LibreOffice Draw and GIMP
Telescopic views of Saturn Jupiter and Mars (north up) as they would be seen in a small telescope, with the same magnification. The image of Mars doesn’t show it, but the white north polar cap will appear at the top or north limb of Mars. The planets are shown at 8 pm tonight, December 28, 2022. Apparent diameters: Saturn 15.82″, its rings 36.84″; Jupiter 39.72″. Mars 15.06″. Mars’ distance is 57.8 million miles (93.0 million kilometers). 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 28, 2022. The night ends on the left with sunrise on the 29th. Click on the image to enlarge it. Created using my LookingUp app and GIMP.
12/23/2022 – Ephemeris – Hunting for the Star of Bethlehem: Venus and Jupiter appear to merge… twice!
This is Ephemeris for Friday, 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 is new today, and won’t be visible.
My favorite astronomical solution to the puzzle of the Star of Bethlehem are two conjunctions of Jupiter and Venus that occurred against the stars of the constellation of Leo the lion 10 months apart on August 12th 3 BCE and June 16th 2 BCE. Leo at that time was associated with Jacob’s son Judah and the land of Judea. The first conjunction occurred in morning twilight. The second in the evening. The first conjunction was close, though someone with excellent eyesight might pick them apart, but the second, would be impossible to separate without a telescope, which wouldn’t be invented for another 16 centuries. And Jesus would have been born in the spring during lambing season when shepherds would have been out all night with their flocks, protecting them. The eclipse that Herod died after would have been on January 10th, 1 BCE, which occurred three months before Passover, enough time for all the palace intrigue* to happen between the lunar eclipse and Passover.
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.
* See yesterday’s post for more information here.
Addendum
The Babylonian concept of the constellation Leo. They called it Urgulu, meaning lion. It represented their god Latarak. The star they called Sharru, meaning King we know as Regulus, which is the diminutive of king.
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. That ghost object that flashed on for one date was the Moon. 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. Created using Stellarium and GIMP.
Venus appeared among Jupiter’s moons on June 16, 2 BC. Of course, no one had a telescope back then. The telescope wouldn’t be invented for another 16 centuries. Stellarium cannot create the real brightness difference between Jupiter and Venus. Venus would be simply dazzling compared to Jupiter, being 12 times brighter. Venus, being an inner planet, shows phases like the Moon. At this time, Venus would have been near its greatest eastern elongation or separation from the Sun, so it would appear as a tiny first quarter moon. Galileo discovered that Venus had phases and orbited the Sun, in the early 17th century. Created using Stellarium.
Merry Christmas!
12/21/2022 – Ephemeris – Winter starts today plus our weekly look at the bright planets
This is Bob Moler with Ephemeris for Wednesday, 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, 2 days before new, will rise at 7:41 tomorrow morning.
Winter begins today at 4:48 pm, just before sunset, from then on until next June the 21st, the Sun, being its farthest south in our skies, will be heading northward again. Let’s see where the naked-eye planets have wandered off to this week. Mars, Jupiter and Saturn will be visible this evening, in the east to southwestern sky at 6 pm. Jupiter is the brightest of the three in the south-southeast, while dimmer Saturn is low in the south-southwest at that hour. Mars is above Orion in the east. Saturn, the westernmost of the bright planets, will set around 9:16 this evening. Venus and Mercury are also in the evening sky, but too close to the setting Sun to be easily spotted. At 6 pm, both will be very low on the southwestern horizon.
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.
Addenda
Winter solstice today
Comparing the sun’s path at the summer and winter solstices. This is a stereographic representation of the whole sky, which distorts the sky and magnifies the size of the sun’s path near the horizon. This chart is for Traverse City, Michigan, about a third of a degree south of 45º north latitude. Created using my LookingUp app.
The bright planets this week
Panoramic view of planets this evening at 7 pm, December 21, 2022. Click on the image to enlarge it. Created using Stellarium.
Telescopic views of Saturn Jupiter and Mars (north up) as they would be seen in a small telescope, with the same magnification. The image of Mars doesn’t show it, but the white north polar cap will appear at the top or north limb of Mars. The planets are shown at 7 pm tonight, December 21, 2022. Apparent diameters: Saturn 15.95″, its rings 37.15″; Jupiter 40.64″. Mars 15.92″. Mars’ distance is 54.6 million miles (88.0 million kilometers). 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 December 21, 2022. The night ends on the left with sunrise on the 22nd. Click on the image to enlarge it. Created using my LookingUp app and GIMP.
Bob Moler's Ephemeris Blog 