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Ephemeris: 02/04/2024 – The rabbit at the feet of Orion

February 6, 2024 Comments off

This is Ephemeris for Tuesday, February 6th. Today the Sun will be up for 10 hours and 1 minute, setting at 5:57, and it will rise tomorrow at 7:55. The Moon, 3 days before new, will rise at 6:44 tomorrow morning.

The constellation of Orion the hunter is in the south in the evening, and he seems to be preoccupied with the charge of Taurus the bull to his upper right. Unnoticed by him and below him is a small constellation called Lepus the hare, made of very dim stars. Good luck trying to make a rabbit out of those stars. In the constellation art that comes with the free application Stellarium. It displays the sky like a planetarium. The artistic constellation of the figure of Canis Major, Orion’s large hunting dog seems to be taking notice of Lepus and is beginning to chase it Lepus the hare is a nice addition to the tableau presented in the winter sky. Stellarium-web.org is a web based version of Stellarium that doesn’t have to be installed on your device.

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

Orion is facing off Taurus the bull. Beneath the Orion's feet is Lepus the hare.
In the southern winter sky the constellation Orion is facing off Taurus the bull. Beneath the Orion’s feet is Lepus the hare. With the planetarium program Stellarium’s art we see that Canis Major, Orion’s larger hunting dog, appears to be chasing Lepus. Created using Stellarium, LibreOffice and GIMP.

Ephemeris: 02/05/2024 – Looking at the star Procyon

February 5, 2024 Comments off

This is Ephemeris for Monday, February 5th. Today the Sun will be up for 9 hours and 59 minutes, setting at 5:56, and it will rise tomorrow at 7:56. The Moon, 3 days past last quarter, will rise at 5:44 tomorrow morning.

The star Procyon is in Orion’s little hunting dog Canis Minor, which contains only one other star. It can be found by using the shoulder stars of Orion, Bellatrix and Betelgeuse, pointing to the left and down a bit to Procyon in the evening. The word Procyon appears to mean “Before the Dog” meaning that rises before the Dog Star, Sirius, even though it is east of it. Procyon is also north of Sirius, which for observers above 30° north latitude does indeed rise before the Dog Star. It is a star like Sirius, though it’s not as bright, or white. Procyon is 11.5 light years away while Sirius is 8.4 light years away. Both have tiny white dwarf companion stars.

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

Here are the constellations of Orion, Canis Major and Canis Minor at about 9 pm February 5th. This includes the bright star Procyon in Canis Minor and Sirius in Canis Major. Created using Stellarium and GIMP.

Ephemeris: 01/31/2024 – Where have the naked-eye planets wandered* off to this week?

January 31, 2024 Comments off

This is Ephemeris for Wednesday, January 31st. Today the Sun will be up for 9 hours and 46 minutes, setting at 5:49, and it will rise tomorrow at 8:02. The Moon, 2 days before last quarter, will rise at 11:56 this evening.

Let’s find out where the naked-eye planets have wandered off to this week. Three of those five planets are now visible. Saturn and Jupiter are the evening planets. Saturn is getting harder to spot low in the west-southwest, nearly succumbing to evening twilight, setting at 7:59 pm. Jupiter will move from high in the south to low in the west by midnight, and will set in the west-northwest at 1:20 am. Venus, the brilliant morning star, will rise in the east-southeast at 6:18 am, and be a brilliant beacon in the morning, shining in the southeast before the bright morning twilight claims it around 7:45 am. As we advance through winter into spring Venus is going to be harder to spot before sunrise.

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

Jupiter and Saturn as they would appear in the southwestern quadrant of the sky around 7 pm or about an hour and a quarter after sunset. Saturn will set an hour later, while Jupiter will last past midnight. Created using Stellarium.
The Moon and the star Spica as they might appear in binoculars or a very low power telescope at 3 am EST (8:00 UT) tomorrow morning, February 1st 2024. The exact position of the Moon with respect to Spica may be different for your longitude as compared to about 86° west longitude where I am. Created using Stellarium.
The Morning Star Venus, left, and the last quarter Moon, right, as they might appear about 7:30 am or about half an hour before sunrise February 1st 2024. Created using Stellarium.

Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope, with the same magnification. At 7 pm January 31, 2024, for Saturn and Jupiter, and 7:30 am on February 1st, for Venus. Apparent diameters: Saturn 15.66″, its rings 36.48″; Jupiter 39.69″; and Venus 12.22″, 85.8% illuminated. There are some Jovian satellite events this evening. At about 7:40 pm Ganymede will appear from behind Jupiter. The image shows the Ganymede label. However, the moon will be hidden at 7:00 pm. Then at 11:12 this evening Ganymede will enter Jupiter’s shadow, and stay hidden until 12:54 am tomorrow morning. The ” symbol means seconds of arc (1/3600th of a degree). Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts) and GIMP.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on January 31, 2024. The night ends on the left with sunrise on February 1st. The labels for Mars and Mercury overlap. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.

* The Greeks called the moving objects in the sky Planetes meaning Wanderers, from which we get the name Planet. In reality the planets do not wander, or move aimlessly, but move in orbits, discovered by Johannes Kepler, in accordance with the laws of gravitation discovered by Isaac Newton and Albert Einstein. The ancients considered the Sun and Moon planets, because they also moved against the “fixed” stars in the sky. This made seven, adding to the five naked eye planets we know today. These seven objects became the names of the days of the week in many countries. We have retained three of them: Sun’s day, Moon’s day, and Saturn’s day. The rest are named for Norse gods and a goddess.

Ephemeris: 01/25/2024 – Where is the full moon in winter?

January 25, 2024 Comments off

This is Ephemeris for Thursday, January 25th. Today the Sun will be up for 9 hours and 31 minutes, setting at 5:41, and it will rise tomorrow at 8:08. The Moon, at full today, will rise at 5:30 this evening.

The exact time that the Moon will be full, at least to the nearest minute is 12:54 this afternoon. Have you ever noticed the placement of the full moon in the sky between winter and summer? The full moon near the winter solstice moves very high at midnight, while the full moon near the summer solstice is seen quite low in the south. For the Moon to be full, it must be nearly opposite the Sun in the sky, so we see it fully illuminated as the Sun does. The Moon’s orbit is close to the Sun’s apparent path in the sky, the ecliptic, which is the projection of the Earth’s orbit of the Sun. So the Moon now is near, and actually a bit north of, where the Sun will be 6 months from now in mid to late July.

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 altitude of the full moon on two dates 6 lunar months apart. In winter the moon rides high in the south (66 degrees altitude). That would be tomorrow morning. Six lunar months later on July 21st the full moon rides very low in the south (19 degrees altitude). This cylindrical view represents the altitude uniformly, but is distorted horizontally with altitude, which is why the winter high altitude full moon appears distorted. Created using Stellarium.

Ephemeris: 01/24/2024 – Where have the planets wandered off to this week?

January 24, 2024 Comments off

This is Ephemeris for Wednesday, January 24th. Today the Sun will be up for 9 hours and 29 minutes, setting at 5:39, and it will rise tomorrow at 8:09. The Moon, 1 day before full, will set at 8:36 tomorrow morning.

Let’s find out where the naked-eye planets have wandered off to this week. Three of those five planets are now easily visible. Saturn and Jupiter are the evening planets. Saturn is getting harder to spot low in the west-southwest, setting at 8:19 pm. Jupiter will move from high in the south to low in the west by midnight, and will set in the west-northwest at 1:40 am. Venus, the brilliant morning star, will rise in the east-southeast at 6:09 am, and be a brilliant beacon in the morning, shining in the southeast before the bright morning twilight claims it around 8 am. Mercury, which rises by 7:03 am might just be visible below and left of Venus by 7:30 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

A panorama of the evening sky
A panorama of the evening sky at 7 pm tonight, January 24, 2024, looking from the east northeast through south to the west to view the Moon, the bright winter stars, Jupiter, in the south, and Saturn, which is close to setting. Click or tap on the image to enlarge it. Created using Stellarium.
The nearly full moon visible in binoculars or small telescopes
The nearly full moon visible in binoculars or small telescopes at 7 this evening, January 24, 2024, showing very little shadow detail. The Moon being fully lit by the Sun and Earth is looking at the Moon from that the same direction. This allows crater rays to be quite visible. The best example of this is the crater Tycho, to the lower right. Rays are thought to be shallow craters caused by the debris kicked out when the impact of the body that created the crater occurred. They show better at full moon because there are no shadows. Otherwise, there would be shadows in these tiny craters, making the rays less visible. Shadows help us see the bigger craters, but only when there are no shadows do these little ejecta craters show up bright. Click or tap on the image to enlarge it. Created using Stellarium, LibreOffice Draw, and GIMP.
Venus and Mercury as seen about 40 minutes before sunrise
Here are Venus and Mercury as seen about 40 minutes before sunrise. That’s about 7:30 am in the Grand Traverse area of Michigan. There’s a good chance that Mercury will be invisible because it’s seen very low in the growing twilight. Mars, just below and left of Mercury, will pass it this weekend, as Mercury moves towards the Sun and Mars moves away. Venus of course is moving towards the Sun also and Mars will pass it about a month from now. Click or tap on the image to enlarge it. Created using Stellarium.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope, with the same magnification. At 7 pm January 24, 2024, for Saturn and Jupiter, and 7:30 am on the 25th, for Venus. Apparent diameters: Saturn 15.74″, its rings 36.66″; Jupiter 40.61″; and Venus 12.58″, 84.2% illuminated. Mercury appears too small to be shown here, but its apparent diameter is 5.52″ and is 82.5% illuminated. Jupiter's moon Ganymede will be eclipsed by Jupiter's shadow and disappear at 7:10 pm, and will emerge from the shadow at 8:53 pm. The ” symbol means seconds of arc (1/3600th of a degree). Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts) and GIMP.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope, with the same magnification. At 7 pm January 24, 2024, for Saturn and Jupiter, and 7:30 am on the 25th, for Venus. Apparent diameters: Saturn 15.74″, its rings 36.66″; Jupiter 40.61″; and Venus 12.58″, 84.2% illuminated. Mercury appears too small to be shown here, but its apparent diameter is 5.52″ and is 82.5% illuminated. Jupiter’s moon Ganymede will be eclipsed by Jupiter’s shadow and disappear at 7:10 pm, and will emerge from the shadow at 8:53 pm. The ” symbol means seconds of arc (1/3600th of a degree). Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts) and GIMP.
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 January 24, 2024. The night ends on the left with sunrise on the 25th. The labels for Mars and Mercury overlap, though the planets do not. Mars is the reddish one. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.

Ephemeris: 01/19/2024 – Finding the Dog Star

January 19, 2024 Comments off

This is Bob Moler with Ephemeris for Friday, January 19th. Today the Sun will be up for 9 hours and 18 minutes, setting at 5:33, and it will rise tomorrow at 8:13. The Moon, 2 days past first quarter, will set at 3:59 tomorrow morning.

In the evening, the great constellation of Orion the hunter can be seen to slowly move from the south-east to the south. Its large rectangle of bright stars is easily visible, even with a full moon. The three stars in a straight line, his belt, tilt downward to the left to a very bright star merrily twinkling lower in the sky. This star is called Sirius, also known as the Dog Star because it’s in the heart of Orion’s larger hunting dog, Canis Major. It is an arc light white star as seen in binoculars or telescope. It is the brightest star in the night sky, and a neighboring star, just twice the distance of the closest star to the Sun at 8.6 light years. Its name, Sirius, has nothing to do with a dog, but is from the Greek meaning scorching for its brightness and sparkling, due to its intense twinkling.

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

Sirius finder
A Sirius finder animation for late January/early February at around 8 pm. Even in bright moonlight the seven bright stars of Orion can be seen. The three stars of Orion’s belt make a great pointer to Sirius. Created using Stellarium, GIMP and LibreOffice Draw (for the arrow).

Ephemeris: 01/18/2024 – A quick guide to Jupiter for the small telescope

January 18, 2024 Comments off

This is Ephemeris for Thursday, January 18th. Today the Sun will be up for 9 hours and 16 minutes, setting at 5:31, and it will rise tomorrow at 8:14. The Moon, 1 day past first quarter, will set at 2:43 tomorrow morning.

Jupiter is the largest planets and is generally the largest appearing planet in a telescope. Venus appears a bit larger than Jupiter only for about four months when it’s the closest it gets to us. There’s always something going on with Jupiter and its 4 Galilean moons which appear to shuffle back and forth from one side to the other of the planet. Jupiter has cloud bands which run parallel to its equator and to the plane of the moon’s orbits. And it has the Great Red Spot, but that spot is not easily visible in small telescopes. Back in the 1950s it was big and brick red. It is since lost a great deal of its redness and size. The moons can hide behind Jupiter or in its shadow or cross in front of the planet. Tonight Jupiter will appear below and right of the Moon.

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

Over this evening (January 18, 2024) Europa and Io will be approaching Jupiter and Io will pass Europa to duck behind Jupiter in occultation just before Jupiter sets for us. Callisto will be moving towards Jupiter also, but slowly. Ganymede will be moving a little bit away, being near the furthest extension of its orbit. Created using Cartes du Ciel (Sky Charts).

Ephemeris: 01/17/2024 – Where have the naked-eye planets wandered off to this week?

January 17, 2024 Comments off

This is Ephemeris for Wednesday, January 17th. Today the Sun will be up for 9 hours and 14 minutes, setting at 5:30, and it will rise tomorrow at 8:15. The Moon, at first quarter today, will set at 1:28 tomorrow morning.

Let’s find out where the naked-eye planets have wandered off to this week. Four of those five planets are now visible. Saturn and Jupiter are the evening planets. Saturn can be seen moving from low in the southwest to setting in the west-southwest at 8:42 pm. Jupiter, left of the Moon tonight will move from high in the south to set in the west-northwest at 2:05 am. Venus, the brilliant morning star, will rise in the east-southeast at 5:58 am, and be a brilliant beacon in the morning, shining in the southeast before the bright morning twilight claims it around 8 am. Mercury will also be visible below and left of Venus, and should be visible by 7:30 am. Mars is below left of Mercury, but really is too dim to be seen.

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

Jupiter, Saturn and the Moon around 7 this evening, January 17, 2024. Jupiter appears brighter and bigger than the Moon, but isn’t. The blooming of the image of stellar type objects is to make them look brighter. The Moon though brighter is shown at its actual apparent size. They look much nicer in the real sky. Created using Stellarium.
The moon tonight about 7 pm this evening, January 17, 2024, as it might appear in binoculars or a small telescope, with selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Venus and Mercury as they might appear about 7:30 tomorrow morning, January 18th 2024, in the growing twilight. Created using Stellarium.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope, with the same magnification. At 7 pm January 17, 2024, for Saturn and Jupiter, and 7:30 am on the 18th, for Venus. Apparent diameters: Saturn 15.84″, its rings 36.89″; Jupiter 41.57″; and Venus 12.96″, 82.6% illuminated. Mercury appears too small to be shown here, but its apparent diameter is 6.02″ and is 74.2% illuminated. The ” symbol means seconds of arc (1/3600th of a degree). Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts) and GIMP.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on January 170, 2024. The night ends on the left with sunrise on the 18th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.

Ephemeris: 01/16/2024 – Watch Saturn’s rings continue to narrow this year.

January 16, 2024 Comments off

This is Ephemeris for Tuesday, January 16th. Today the Sun will be up for 9 hours and 12 minutes, setting at 5:29, and it will rise tomorrow at 8:15. The Moon, 1 day before first quarter, will set at 12:12 tomorrow morning.

After the Moon, the next targets for the small telescope are the planets. Saturn is getting pretty low in the southwest now so there’s only about another month when it’s really visible in steady skies. Of course Saturn has those beautiful rings which are now getting very thin and by the end of March next year they will be edge on to us and then begin to open up through the rest of 2025. One’s first impression of Saturn is generally that besides the rings it’s really tiny. It averages almost a billion miles from the Earth, and even though it’s the second-largest planet it looks very tiny at that distance. Saturn’s largest moon Titan can be seen near the planet it is the second-largest moon in the solar system.

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

This is not a photograph of Saturn. It is an image produced by the programCartes du Ciel or Sky Charts which is a free app for the PC. The rings are narrowing as Saturn approaches an equinox, which will be, for its northern hemisphere, the autumnal equinox. The rings, which orbit over Saturn’s equator, will go edge on to the Earth on March 23rd next year. The rings are about 150,000 miles in diameter however they are less than 100 feet thick so when they go edge-on to us, they will disappear, and so we will see only the thin shadow of the rings projected on the planet. Later, on May 6th, the Sun will pass through the ring plane, the actual date of the equinox, so they will not be illuminated and cast no shadow on the planet. So even though the rings open up a tiny bit for us, the rings will be dark and only appear as a black line against the planet.

Ephemeris: 01/15/2024 – The Moon is a great first target for that new telescope

January 15, 2024 Comments off

This is Bob Moler with Ephemeris for the Martin Luther King Jr. Holiday, Monday, January 15th. Today the Sun will be up for 9 hours and 11 minutes, setting at 5:27, and it will rise tomorrow at 8:16. The Moon, 2 days before first quarter, will set at 10:55 this evening.

The Moon is a great first target for that Christmas telescope. Over the weekend we began a new lunar month so that the Moon appears as a crescent in the southwestern sky after sunset. The first time I looked at the Moon with the telescope or looked at anything in the sky, actually, I found it very difficult to aim the telescope correctly. The field of view of the telescope is very small compared to what you can see with the naked eye. Always start with the lowest power eyepiece because it gives the widest field of view for finding what you’re looking for. It does take a little practice to learn how to aim a telescope, but the moon is a wonderful object to look at because it’s really big and very bright.

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

This may be what the waxing Crescent Moon looks like in a small telescope tonight, January 15th 2024. Select features of the Moon are annotated including several I haven’t mentioned before. There’s the keyhole looking constellation on the edge of Mare Fecunditatis named Gutenberg after the inventor of the printing press and also Franklin after Benjamin Franklin. Created using Stellarium, LibreOffice Draw, and GIMP.