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Ephemeris: 01/23/2025 – Conflict in the heavens

January 23, 2025 Comments off

This is Ephemeris for Thursday, January 23rd. Today the Sun will be up for 9 hours and 28 minutes, setting at 5:39, and it will rise tomorrow at 8:09. The Moon, 2 days past last quarter, will rise at 4:15 tomorrow morning.

There are several instances in the Greek heavens where constellations appear to interact with one another. This is true with Orion the hunter and Taurus the bull. Taurus, whose face is the letter V of stars, near Jupiter this year. The orangish star Aldebaran as his angry bloodshot eye is charging down on Orion, who has raised a lion skin shield on one arm and an upraised club in the other, ready to strike. They have been frozen in this pose for millennia. Stars below and right of the letter V of the Bull’s face suggest the front part of his body and his front legs charging at Orion. Orion also has two hunting dogs, Canis Major and Canis Minor. Canis Major with its dazzling star Sirius will rise around 6:21 on a line extending down from Orion’s belt.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

Looking southeast at 8 PM in late January 2025, a conflict frozen in time for millennia.
Looking southeast at 8 PM in late January 2025, a conflict frozen in time for millennia. Taurus the bull, with those wicked horns, is charging Orion the hunter. His lion skin shield is upraised, and his club ready to strike. This year Jupiter intrudes on the tableau. Created using Stellarium and GIMP.

Perhaps Jupiter is not intruding, because the Roman god Jupiter is the Greek god Zeus, who turned himself into a bull to carry off the maiden Europa. And Europa is with him still as Jupiter’s moon, and target of NASA’s recently launched Europa Clipper spacecraft.

Categories: Constellations, Ephemeris Program, Mythology, Observing Tags: , , ,

Ephemeris: 01/22/2025 – Let’s take our weekly look at the whereabouts of the naked-eye planets

January 22, 2025 Comments off

This is Ephemeris for Wednesday, January 22nd. Today the Sun will be up for 9 hours and 26 minutes, setting at 5:38, and it will rise tomorrow at 8:10. The Moon, 1 day past last quarter, will rise at 3:07 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. At 8 PM this evening four of the five naked eye planets will be out. Starting from the West we have Venus the brightest of all low in the west southwest. Directly below it will be the much dimmer Saturn. Jupiter, the second-brightest planet will be high in the southeast. Below and right of it is the letter V shape of stars that is the head of Taurus the bull. Farther below is the spectacular constellation of Orion the hunter. The 4th planet out is Mars, the third brightest planet now, with its distinctive reddish hue, near the star Pollux in Gemini. The fifth naked eye planet, Mercury, is too close to the Sun in the morning to be visible.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

An 8 PM January 22, 2025, planet panorama.
An 8 PM January 22, 2025 planet panorama. Venus and Saturn are in the west-southwest, and Jupiter is in the southeast. Mars is in the east. The orange line is the ecliptic, the path of the Sun in the sky, and near which all the planets are seen. Also shown are the zodiacal constellations. Click or tap on the image to enlarge it. Created using Stellarium.
The Moon as it might appear through a small telescope tomorrow morning, January 23, 2025
The Moon as it might appear through a small telescope tomorrow morning, January 23, 2025. Selected features are labeled. Created using Stellarium, LibreOffice draw, and GIMP.
Telescopic Saturn, Venus, Jupiter and Mars (north up) as they would be seen in a small telescope with the same magnification
Telescopic Saturn, Venus, Jupiter and Mars (north up) as they would be seen in a small telescope with the same magnification. All the planets are shown for tonight, 8 PM, January 22, 2025. Apparent diameters: Saturn 16.1″, its rings 37.5″, 3.3 degrees from edge on (closing); Venus 28.4″, 43.8% illuminated; Jupiter 44.6″; Mars, 14.3″. Planetary surface detail is more subtle than shown here. Jupiter’s moon Europa is behind the planet and will reappear on the east or trailing side of the planet around midnight EST (5:00 UT). The ” means seconds of arc, or 1/3600th of a degree. Click or tap 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 22, 2025. The night ends on the left with sunrise on the 23rd. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, January 22 and 23, 2025
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, January 22 and 23, 2025. Some of the columns are self-explanatory, others not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , ,

Ephemeris: 01/21/2025 – How to find the Great Orion Nebula

January 21, 2025 Comments off

This is Ephemeris for Tuesday, January 21st. Today the Sun will be up for 9 hours and 24 minutes, setting at 5:36, and it will rise tomorrow at 8:11. The Moon, at last quarter today, will rise at 2:01 tomorrow morning.

The constellation Orion the hunter is in the southeast at 8 PM. Its rectangle of four stars lean to the left and frame his belt of three stars in a straight line in the center of the rectangle. Below the belt is what appear to the unaided eye as three more stars arranged in a shorter straight line, his sword. Binoculars aimed at the middle stars of the sword will find a glowing haze around those stars. That is the Great Orion Nebula, also known as Messier 42 or M 42. It is the birthplace of stars, illuminated by a clutch of four hot young stars. Besides stars and protostars being born in the nebula, there are also many double planets not belonging to stars discovered by the James Webb Space Telescope. The planets are only detectable in the infrared, Webb’s specialty.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

An animated GIF for finding the Great Orion nebula, M 42
An animated GIF for finding the Great Orion nebula, M 42. Orion is oriented as it would appear in the southeast at 8:00 PM in late January. The nebula appears as a glow around what looks, to the naked eye, the center star of Orion’s sword. The glow of the nebula may be visible to the naked eye and in binoculars. But a low power telescope is the best way to see it. Created using stellarium, LibreOffice draw, and GIMP.
The stars and nebulae in Orion's Sword are photographed here in one of GTAS' members Dan Dall'Olmo's earlier photographs of the Great Orion Nebula
The stars and nebulae in Orion’s Sword are photographed here in one of GTAS’ members Dan Dall’Olmo’s earlier photographs of the Great Orion Nebula. The three stars of the sword seen by the naked eye are actually multiple stars rather than the single stars as in Orion’s Belt. In telescopes only the brightest part of the nebula shows up to the to the eye. However, the lower the power the brighter the nebula, and the more is visible. One of the cool things that is visible in a telescope is that blue streamer coming down on the left side of the nebula. It is about 1,344 light years away.

The blog’s archive has many other posts about the Great Orion Nebula and other nebulae in Orion.

Categories: Ephemeris Program, Nebula, Observing Tags: , , ,

Ephemeris: 01/20/2025 – The planets augment the Winter Hexagon

January 20, 2025 Comments off

This is Ephemeris for Martin Luther King Jr. Day, Monday, January 20th. Today the Sun will be up for 9 hours and 22 minutes, setting at 5:35, and it will rise tomorrow at 8:12. The Moon, 1 day before last quarter, will rise at 12:56 tomorrow morning.

The winter circle or more properly hexagon, seen in the winter sky this evening, has the addition of two planets, and they’re in the proper location so that they don’t spoil the hexagon. We start at the top with the star Capella high in the east. We move clockwise downward to Jupiter and below it the star Aldebaran. We drop lower to Orion’s knee and the star Rigel, then down to Sirius, low in the southeast, the brightest nighttime star, but doesn’t hold a candle to Jupiter. Then we go above left to Procyon and upwards and left to Mars, which is near Pollux, and finally back up to Capella. That’s that is our winter hexagon right now, so take it in while you can, before Jupiter and Mars move off and mess it up.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

The Winter Hexagon, right now, with Jupiter replacing Aldebaran and Mars replacing Pollux
The Winter Hexagon, for tonight at 8 PM, January 20, 2025, with Jupiter replacing Aldebaran and Mars replacing Pollux, but still keeping the basic shape of the hexagon. This will soon change as Jupiter and especially Mars eventually begin to move eastward. Created using Stellarium, LibreOffice Draw, and GIMP.

As for events happening on Earth: Resist!

Categories: Asterism, Ephemeris Program, Observing, Planets, Stars Tags: , , , , , , , ,

Ephemeris: 01/17/2025 – Venus passes Saturn in conjunction tomorrow

January 17, 2025 Comments off

We end this week of planetary events with this post:

This is Ephemeris for Friday, January 17th. 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, halfway from full to last quarter, will rise at 9:44 this evening.

Venus will pass the slower moving Saturn at about 11:00 tomorrow morning, so tonight and Saturday night are your best times to see these two planets at their closest. They will probably be slightly closer tomorrow night than tonight. This apparent meeting of two planets is called a conjunction. The two planets are not anywhere close to each other, in fact Venus is closer than the Sun right now, and Saturn is 10 times farther away than the Sun. They just happen to be near the same line of sight. From there both will lose their battle with evening twilight. Saturn will make it back to conjunction with the Sun first, ten days before Venus. Before that Mercury will pass in conjunction with Venus.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

Saturn and Venus are seen on three evenings around 6:30 PM: January 17th, 18th, and 19th
Saturn and Venus are seen on three evenings around 6:30 PM: January 17th, 18th, and 19th. The step is the sidereal day, not the solar day, so the stars would not move, and the motion shown is actually the planets motion against the stars. The sidereal day is 3 minutes 56 seconds shorter than the 24 hour day we call a solar day. Which means the stars set earlier by that amount each night. Created using Stellarium and GIMP.
An oblique perspective view of the solar system showing the line of sight from Earth to Venus and Saturn for the conjunction of January 18th 2025
An oblique perspective view of the solar system showing the line of sight from Earth to Venus and Saturn for the conjunction of January 18th 2025. Created using my LookingUp app , LibreOffice Draw, and GIMP.

Categories: Conjunction, Ephemeris Program, Naked-eye planets, Observing Tags: ,

Ephemeris: 01/16/2025 – Mars has the second most eccentric orbit of all the planets

January 16, 2025 Comments off

This is Ephemeris for Thursday, January 16th. 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, 3 days past full, will rise at 8:37 this evening.

The planet Mars has the second most eccentric orbit of all the planets, after Mercury. But with yesterday’s opposition of Mars it only came down to 59.7 million miles away. At its absolute closest to us, which occurred in 2003, Mars got down to 34.6 million miles away. Since Mars orbits the Sun in little less than two earth years we catch up to it a little farther down in its orbit every time. Mars closest approaches occur every 15 or 17 years. The last close approach was in 2018. The next closest approach will occur in 2035 a span of 17 years. The closest approach before 2018 occurred in 2003 the span between those two was 15 years. Even at closest approach Martian detail is hard to see with a small telescope.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

Looking at the apparent size of Mars for four oppositions
Looking at the apparent size of Mars for four oppositions. The first, in 2003, is the closest Mars has gotten to the Earth for the last 50,000 years according to some astronomers. The next closest approach was in 2018 the next Mars image shows how Mars appears in the current, unfavorable opposition. The last is the next closest appearance opposition which will be in 2035. Martian features are more subtle than they appear here. The large feature on the right side of each image is called Syrtis Major which translates to Great Swamp. The bright round spot below it is what is believed to be a large crater called Hellas. Created using Cartes Du Ciel (Sky Chart), assembled with GIMP, and labeled using LibreOffice Draw.
The Mars oppositions from the last closest opposition in 2018 to the next closest opposition in 2035
The Mars oppositions from the last closest opposition in 2018 to the next closest opposition in 2035, including tomorrow’s opposition of January 15th 2025. The tick marks on the orbits specify the perihelion or the closest a planet approaches the Sun and aphelion, the farthest. They are labeled for Mars, but they are not for the Earth. Earth’s perihelion comes in early January and aphelion occurs in early July. The difference in Earth’s perihelion and aphelion is only 3 million miles, for Mars it’s 30 million. Created using my LookingUp app, LibreOffice Draw and GIMP.
Categories: Ephemeris Program, Observing Tags: , ,

Ephemeris: 01/15/2025 – Our weekly look at the whereabouts of the naked-eye planets

January 15, 2025 Comments off

This is Ephemeris for Wednesday, January 15th. Today the Sun will be up for 9 hours and 12 minutes, setting at 5:28, and it will rise tomorrow at 8:15. The Moon, 2 days past full, will rise at 7:27 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. At 8 PM this evening four of the five naked eye planets will be out. Starting from the West we have Venus the brightest of all low in the west southwest. Left and a bit above it is Saturn. They will appear at their closest Friday and Saturday nights. Jupiter, the second-brightest planet will be high in the southeast. The 4th planet out is Mars, which is at opposition from the Sun tonight. Mars will not get this close to the Earth again until 2031. It shines with its reddish hue a third as bright as Jupiter in the eastern sky. On unusually close approaches, Mars can actually outshine Jupiter. The fifth naked eye planet, Mercury, is too close to the Sun on the morning side to be visible.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

A 8 PM January 15, 2025 planet panorama
A 8 PM January 15, 2025 planet panorama. Venus and Saturn are in the west-southwest, and Jupiter is in the southeast. Mars is in the east-northeast. The waning gibbous Moon is rising in the east-northeast. The first magnitude stars are also named. Click or tap on the image to enlarge it. Created using Stellarium.
The Moon tonight at 9 PM, January 15, 2025, as it might appear in a small telescope
The Moon tonight at 9 PM, January 15, 2025, as it might appear in a small telescope. Selected features are labeled. Created using Stellarium, LibreOffice Draw, and GIMP.

Translations of some lunar feature names according to Virtual Moon Atlas

Mare Cognitum – Sea of Knowledge
Mare Crisium – Sea of Crises
Mare Fecunditatis – Sea of Fruitfulness
Mare Frigoris – Sea of Cold
Mare Humorum – Sea of Moisture
Mare Imbrium – Sea of Showers
Mare Nectaris – Sea of Nectar
Mare Nubium – Sea of Clouds
Mare Serenitatis – Sea of Serenity
Mare Tranquillitatis – Sea of Tranquility
Mare Vaporum – Sea of Vapors
Montes Alpes – Alps Mountains
Montes Apenninus – Apennines Mountains
Oceanus Procellarum – Ocean of Storms
Sinus Iridium – Bay of Rainbows
Sinus Medii – Central Bay

Mare is pronounced Mar-e. Craters are named for persons, real or otherwise.

Telescopic Venus, Saturn, Jupiter and Mars
Telescopic Venus, Saturn, Jupiter and Mars (north up) as they would be seen in a small telescope with the same magnification. All the planets are shown for tonight, 8 PM, January 15, 2025. Apparent diameters: Venus 26.1″, 47.8% illuminated; Saturn 16.2″, its rings 37.8″, 3.7 degrees from edge on (closing); Jupiter 45.5″; Mars, 14.6″. Planetary surface detail is more subtle than shown here. Jupiter’s moon Europa is behind the planet and will reappear on Callisto’s side of the planet at 9:22 PM (2:22 UT). The ” means seconds of arc, or 1/3600th of a degree. Click or tap 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 15, 2025. The night ends on the left with sunrise on the 16th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, January 15 and 16, 2025. Some of the columns are self-explanatory, others not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

Categories: Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , ,

Ephemeris: 01/14/2025 – Mars reaches opposition tomorrow – What that means

January 14, 2025 Comments off

This is Ephemeris for Tuesday, January 14th. Today the Sun will be up for 9 hours and 10 minutes, setting at 5:27, and it will rise tomorrow at 8:16. The Moon, 1 day past full, will rise at 6:14 this evening. | Tomorrow the planet Mars will be in opposition to the Sun. That means it will rise at sunset and set at sunrise. This is the time we are closest to Mars or near closest to Mars of its current pass. Mars comes in opposition from the Sun about every 26 months on average. Currently, Mars is farther from the Sun than average. It has a large swing in distances from the Sun and so at this time moves slower than average. The time between oppositions is only 25 months currently. The various space agencies know that opposition time is the best time to launch spacecraft to Mars. However, they launch several months ahead of opposition for the spacecraft to arrive several months after opposition for the least amount of energy needed for the journey.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

The Mars oppositions from the last closest opposition in 2018 to the next closest opposition in 2035
The Mars oppositions from the last closest opposition in 2018 to the next closest opposition in 2035, including tomorrow’s opposition of January 15th 2025. The tick marks on the orbits specify the perihelion or the closest a planet approaches the Sun and aphelion, the farthest. They are labeled for Mars, but they are not for the Earth. Earth’s perihelion comes in early January and aphelion occurs in early July. The difference in Earth’s perihelion and aphelion is only 3 million miles, for Mars it’s 30 million. We’ll revisit this on Thursday. Created using my LookingUp app, LibreOffice Draw and GIMP.
Categories: Concepts, Ephemeris Program, Observing Tags: ,

Ephemeris: 01/13/2025 – The Moon will pass in front of Mars tonight

January 13, 2025 Comments off

This is Ephemeris for Monday, 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, at full today, will rise at 5:00 this evening.

Tonight we will be able to witness, if it’s clear of course, an event between the Moon and the planet Mars. The Moon will pass in front of the planet Mars this evening. The event is called an occultation. If you think of tonight’s full moon as being a clock face, Mars will disappear at about the 8 o’clock position of the Moon’s edge at 9:13 PM and will reappear near the 1 o’clock position at 10:20 PM. These times should be within a minute or two depending on where you are in the listening area. However, because the full moon is so bright it will be best to view this with binoculars, starting earlier in the evening so you can find Mars against the brightness of the Moon, while it’s still far away from the Moon’s edge. Good luck, and clear skies!

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

The occultation of Mars tonight, showing Mars' ingress and egress
The occultation of Mars tonight, January 13th 2025, showing Mars’ ingress at 9:13 PM in the Grand Traverse area and the egress at 10:10 PM. Mars is shown brighter and larger than it will appear. It may be hard to detect near the Moon with binoculars, and probably impossible with a naked eye, so start searching for it early. Created using Stellarium, LibreOffice Draw, and GIMP.
A world map showing the area where the occultation will be visible
A world map showing the area where the occultation will be visible, which includes the 48 contiguous United States, a good chunk of Canada, across the Atlantic and into West Africa. Don’t be fooled by the date of January 14th. Midnight January 14th Universal Time (UT) starts at 7:00 PM Eastern Standard Time on the 13th. Created using Occult 4.

If you are not in Northern Michigan the use of a program such as Stellarium will allow you to preview the occultation to derive the times of the ingress and egress times and positions for your location.

Categories: Astronomical Event, Ephemeris Program, Observing, Occultation Tags: ,

Ephemeris: 01/08/2025 – A weekly look at the whereabouts of the naked-eye planets

January 8, 2025 Comments off

This is Ephemeris for Wednesday, January 8th. Today the Sun will be up for 9 hours and 1 minute, setting at 5:20, and it will rise tomorrow at 8:18. The Moon, 2 days past first quarter, will set at 4:05 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. At 8:00 PM this evening four of the five naked eye planets will be out. Starting from the West we have Venus the brightest of all low in the west southwest. Above and left of that is Saturn. The waxing gibbous moon is high in the South at that time. Jupiter, the second-brightest planet will be high in the southeast. The 4th planet out is Mars which is low in the east northeast with its reddish hue giving it away. Next Monday the Moon will pass directly over the planet Mars in our evening sky. The fifth naked eye planet, Mercury, is too close to the Sun on it morning side to be visible.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

A 7 PM January 8, 2025, planet panorama
A 7 PM January 8, 2025 planet panorama. Venus and Saturn are in the southwest, and Jupiter is in the east. Mars is just rising in the east-northeast. Click or tap on the image to enlarge it. Created using Stellarium.
The Moon tonight, January 8, 2025, as it might appear in a small telescope
The Moon tonight, January 8, 2025, as it might appear in a small telescope. Selected features are labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Venus, Saturn, Jupiter and Mars
Telescopic Venus, Saturn, Jupiter and Mars (north up) as they would be seen in a small telescope with the same magnification. All the planets are shown for tonight, 7 PM, January 8, 2025. Apparent diameters: Venus 24.1″, 51.6% illuminated; Saturn 16.4″, its rings 38.2″, 4.0 degrees from edge on (closing); Jupiter 46.3″; Mars, 14.5″. Planetary surface detail is more subtle than shown here. Jupiter’s moon Io will disappear behind the planet later in the evening and reappear on the other side after midnight. The ” means seconds of arc, or 1/3600th of a degree. Click or tap 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
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on January 8, 2025. The night ends on the left with sunrise on the 9th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, January 8 and 9, 2025. Some of the columns are self-explanatory, others not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

Categories: Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , ,