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Ephemeris: 01/12/2024 – Mercury is at greatest western elongation from the Sun today
This is Ephemeris for Friday, January 12th. Today the Sun will be up for 9 hours and 6 minutes, setting at 5:24, and it will rise tomorrow at 8:17. The Moon, 1 day past new, will set at 6:49 this evening.
The planet Mercury is reaching its greatest western elongation or separation west of the Sun today at a 23.5 degrees angle, which is pretty good actually, although the angle above the horizon where we see Mercury at this point in the year is not the best. However, Venus can be used to spot Mercury because Mercury will be to the lower left of Venus. Binoculars are always helpful in spotting Mercury for the first time. From now until about a week from now Mercury will not move very much in relationship to Venus, but it will be getting somewhat brighter as its phase goes from half illuminated to more gibbous towards full. Early in the spring it will be seen in the evening sky, at a little bit better angle above the horizon, although it will be it will not be as far away from the Sun. Created using Stellarium and GIMP.
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
Ephemeris: 01/10/2024 – Where have the naked-eye planets wandered off to this week?
This is Ephemeris for Wednesday, January 10th. Today the Sun will be up for 9 hours and 2 minutes, setting at 5:21, and it will rise tomorrow at 8:18. The Moon, 1 day before new, will rise at 8:59 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. Mars will rise too close to sunrise to be seen, however. Saturn and Jupiter are the evening planets. Saturn can be seen moving from low in the southwest to setting in the west-southwest at 9:06 pm. Jupiter will be moving from high in the south to the west by midnight and will set at 2:31 am. Venus, the brilliant morning star, will rise in the east-southeast at 5:44 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.
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
Ephemeris: 01/09/2024 – Betelgeuse, Betelgeuse, nope I’m not saying it again
Jan 9. This is Ephemeris for Tuesday, January 9th. 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 before new, will rise at 8:04 tomorrow morning.
The constellation Orion has two first magnitude stars, the most famous of these is Betelgeuse. It is a red supergiant star in Orion’s shoulder. Its name actually means Armpit of the Central One. Betelgeuse is about 500 light years away, and it is many hundreds of thousands of times brighter than the Sun, and it’s thought to be almost as big as the orbit of Jupiter. For all its size it’s only about 20 times the mass of the Sun. Some call it a red-hot vacuum. Betelgeuse has been interesting lately, first dimming for a period of time and now somewhat brighter than normal. Astronomers are wondering what’s going on with it. Betelgeuse is a type of star that will end with the supernova explosion. The question is when. Perhaps sometime in the next 100,000 years.
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
Ephemeris: 01/08/2024 – Orion vs Taurus: conflict for the ages
This is Ephemeris for Monday, January 8th. Today the Sun will be up for 9 hours even, setting at 5:19, and it will rise tomorrow at 8:19. The Moon, 3 days before new, will rise at 6:58 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 with orangish 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 7:30 on a line extended down from Orion’s belt.
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
Ephemeris: 01/05/2024 – The Great Orion Nebula
This is Ephemeris for Friday, January 5th. The Sun will rise at 8:20. It’ll be up for 8 hours and 56 minutes, setting at 5:16. The Moon, 2 days past last quarter, will rise at 3:18 tomorrow morning.
The constellation Orion the hunter is in the south-southeast at 9 p.m. Its upright rectangle of four stars frame his belt of three stars in a straight line and still tilt a bit to the left. Below the belt is what appear to the unaided eye as three more stars arranged vertically, 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 M42. It is the birthplace of stars, and is even 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). They may be different for your location.
Addendum
Ephemeris: 01/04/2024 – Viewing Orion’s Belt
This is Ephemeris for Thursday, January 4th. The Sun will rise at 8:20. It’ll be up for 8 hours and 55 minutes, setting at 5:15. The Moon, 1 day past last quarter, will rise at 2:10 tomorrow morning.
Orion’s belt of three stars is one of the most noticeable star groupings in the sky. There are no other groups of three bright stars in a straight line visible anywhere else in the sky. The star’s names from left to right are Alnitak, Alnilam and Mintaka. They are actually a bit farther away than the other bright stars of Orion. Alnilam, the center star, is over three times the distance of red giant Betelgeuse above them and over twice as far as blue white giant star Rigel below them. Alnilam is 375 thousand times brighter than the Sun. These three stars were also known as Frigga’s Spindle by the Norsemen. Frigga, also known as Freya, is the goddess from which we get the name of the day of the week we call Friday.
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
Ephemeris: 12/27/2023 – Our last look at the naked-eye planets for 2023
This is Ephemeris for Wednesday, December 27th. Today the Sun will be up for 8 hours and 49 minutes, setting at 5:08, and it will rise tomorrow at 8:19. The Moon, 1 day past full, will rise at 5:30 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. Mercury and Mars rise too close to sunrise to be seen. Saturn and Jupiter are the only evening planets. Saturn can be seen moving from low in the southwest to setting in the west-southwest at 9:54 pm. Jupiter will be moving from the high in the southeast to the west-southwest, by midnight and will set at 3:24 am. The Moon, the night after it being full, will be in Gemini tonight, not that any of its stars will be visible, making the sky bright. Venus, the brilliant morning star, will rise in the east-southeast at 4:56, am, and be a brilliant beacon in the morning, shining in the southeast by before the bright morning twilight claims it around 8 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
Ephemeris: 12/25/2023 – This year’s Christmas Stars
Merry Christmas! This is Ephemeris for Christmas Day, Monday, December 25th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:07, and it will rise tomorrow at 8:18. The Moon, 1 day before full, will set at 8:25 tomorrow morning.
The real star of Bethlehem is probably not what is popularly depicted as a bright star in the sky, rather it was something subtle, only noticed by some astrologers. However, gracing our skies tonight we do have, in the morning and again in the evening, two bright star-like objects. I call them star-like objects because they’re planets. In the morning we have brilliant Venus off in the southeast at 7:30 in the morning, and early in the evening we have bright Jupiter in the south. Jupiter is bright enough that when Venus is not in the sky it is sometimes mistaken for it, although Venus would never be seen in the south* in the evening, it’s always too close to the Sun. Again have a Merry Christmas!
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.
* Except from the North Pole. From there all directions are south.
Addendum
Ephemeris: 12/20/2023 – Where are the naked-eye planets this week?
This is Bob Moler with Ephemeris for Wednesday, December 20th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:04, and it will rise tomorrow at 8:16. The Moon, 1 day past first quarter, will set at 2:21 tomorrow morning.
Let’s find out where the naked-eye planets have wandered off to this week. Three of those five planets are now visible, but Mercury sets too close to sunset to be seen. And Mars rises too close to sunrise. Saturn and Jupiter are the only evening planets visible. Saturn can be seen moving from low in the south-southwest to setting in the west-southwest at 10:19 pm. Jupiter will be moving from the high in the southeast to the west-southwest, and will be up most of the night until 3:53 am. The slightly waxing gibbous Moon will be seen to the right of Jupiter tonight. Venus, the brilliant morning star, will rise in the east-southeast at 4:56, am, and be a brilliant beacon in the morning, shining in the southeast by 7 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
Ephemeris: 12/18/2023 – The Moon tonight
This is Bob Moler with Ephemeris for Monday, December 18th. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:03, and it will rise tomorrow at 8:15. The Moon, 1 day before first quarter, will set at 11:50 this evening.
Tonight’s Moon is just about exactly one day before first quarter it’s a six-day-old Moon. Each quarter of the revolution of the moon is just about one week. A lunar month comes out to 29 1/2 days which is a little bit more than 28 days which should be four weeks. That’s pretty close. The illuminated part of the moon that we’re looking at first quarter I consider the most interesting half of the Moon with a good mixture of lowlands which are the seas which are the dark grayer parts of the Moon and the highlands which are very roughly cratered, and are actually higher than the lowlands, or the seas. So if you could put water on the Moon without evaporating it, this is where the water would be. Early telescopic astronomers did think that’s where the water was. Of course the Moon has no atmosphere and the water would just evaporate.
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
Bob Moler's Ephemeris Blog 