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Ephemeris: 01/30/2025 – What’s up with Betelgeuse
This is Bob Moler with Ephemeris for Thursday, January 30th. Today the Sun will be up for 9 hours and 45 minutes, setting at 5:49, and it will rise tomorrow at 8:02. The Moon, 1 day past new, will set at 7:20 this evening.
The constellation Orion is in the southeast at 8 PM, so what’s up with Betelgeuse. Betelgeuse is the bright reddish upper leftmost star of the torso of Orion the hunter, it’s in his shoulder. Betelgeuse has been acting up lately. In 2019 and 2020 Betelgeuse had dimmed significantly. Astronomers didn’t know why at the time, but found out later that it ejected a large cloud of gas and dust which blocked the light from the star. Since then Betelgeuse has increased its brightness significantly, so it’s much brighter than normal. Again, we don’t exactly know why. Some have speculated that Betelgeuse is will soon go supernova. We’ve known that for a while, but soon is measured in hundreds of thousands of years. So astronomers are keeping an eye on Betelgeuse to see what happens next.
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
Ephemeris: 01/23/2025 – Conflict in the heavens
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
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.
Ephemeris: 01/21/2025 – How to find the Great Orion Nebula
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
The blog’s archive has many other posts about the Great Orion Nebula and other nebulae in Orion.
Ephemeris: 12/27/2024 – Orion’s story
This is Ephemeris for Friday, December 27th. 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, 3 days before new, will rise at 6:32 tomorrow morning.
It may seem unfair that the greatest mythological hero Hercules gets a little constellation of dim stars on the border between the spring and summer constellations, while Orion, a virtual nobody, a hard luck hero gets the splashiest constellation in the sky. Orion’s claim to fame or infamy is how he died. And the Greeks had two completely different stories on how that happened. First, that he was killed by a sting of a giant scorpion represented by the constellation Scorpius, and second that he was killed by an arrow shot by the goddess he loved, the arrow being deflected by her brother who didn’t want her to marry a mere mortal.
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
Ephemeris: 12/02/2024 – Orion is rising in the evening
This is Ephemeris for Monday, December 2nd. Today the Sun will be up for 9 hours and 1 minute, setting at 5:03, and it will rise tomorrow at 8:02. The Moon, 1 day past new, will set at 5:47 this evening.
In the east, the central winter constellation Orion the hunter throws a leg over the horizon between 8 and 9 p.m. as Robert Frost told in his poem Star-Splitter. The upright rectangle that is his body on December evenings is tilted to the left as he rises, with a bright red star Betelgeuse at the top left of the rectangle, his shoulder. At the opposite corner is blue-white Rigel, a knee. In the center of the rectangle is a line of three stars nearly vertically aligned as he rises, which represents his belt. The stars of Orion’s belt are how many folks can find him. The Anishinaabek native peoples of this area call him the Wintermaker whose arms are held wide to encompass the winter stars. His rising in the evening heralds the coming of winter.
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
Ephemeris: 11/25/2024 – How to find Taurus the bull
This is Ephemeris for Monday, November 25th. Today the Sun will be up for 9 hours and 12 minutes, setting at 5:06, and it will rise tomorrow at 7:54. The Moon, 3 days past last quarter, will rise at 3:15 tomorrow morning.
Low in the east at 8 this evening and below the beautiful Pleiades star cluster is Taurus the bull. His face is a letter V shape of stars lying on its side, the star cluster Hyades, with the bright orange-red star Aldebaran at one tip of the V as its angry bloodshot eye. Aldebaran is actually about halfway between us and the cluster. Tonight it is to the right of the brilliant planet Jupiter. The Pleiades star cluster is in his shoulder. Taurus is seen charging downward at that hour, the rising constellation of Orion. Taurus in Greek mythology was the form the god Zeus assumed when he carried off the maiden Europa. Europa’s still with him as a moon orbiting Zeus’ Roman equivalent, the planet Jupiter.
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
Ephemeris: 05/27/2024 The evening sky is transitioning into summer
This is Bob Moler with Ephemeris for Memorial Day, Monday, May 27th. Today the Sun will be up for 15 hours and 14 minutes, setting at 9:17, and it will rise tomorrow at 6:02. The Moon, 3 days before last quarter, will rise at 1:36 tomorrow morning.
The sky tonight at 10:30 is beginning to show the transition from spring to summer. Antares in Scorpius is very low in the southeast, rising and chasing away Orion who has disappeared in the West. According to Greek mythology, at least in one story, Orion was killed by the sting of a giant scorpion and so neither he nor Scorpius the scorpion can be in the sky at the same time. The bright star Spica in Virgo the virgin is due South at that time, with Leo the lion in the southwest. Very high in the southeast is the star Arcturus. The Big Dipper is overhead. And in the east-northeast high up this is the bright star Vega, one of the stars of the summer triangle. The second star of the triangle Deneb is lower in the northeast. The third star has yet to rise.
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
Ephemeris: 03/12/24 – The story of the twins of Gemini
This is Bob Moler with Ephemeris for Tuesday, March 12th. Today the Sun will be up for 11 hours and 46 minutes, setting at 7:45, and it will rise tomorrow at 7:57. The Moon, 2 days past new, will set at 11:07 this evening.
A week ago I talked about how to find the constellation of Gemini the twins above and to the left of the constellation Orion. Today I’ll talk about their story. Gemini the twins are fraternal twins, Castor and Pollux. Their namesake stars are the brightest in Gemini, with Castor above and the brighter Pollux below and left. Pollux was fathered by the god Zeus who raped his mother in the Leda and the Swan incident, while Castor was fathered by a mortal. They both went on the quest for the Golden Fleece with Jason and the Argonauts. Unfortunately Castor was killed. Pollux loved his brother so much he petitioned Zeus for him to die also and join Castor in the underworld. Instead, Zeus placed them both in the sky where we see them as Gemini.
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
Ephemeris: 03/07/2024 – There’s a unicorn in there somewhere
This is Bob Moler with Ephemeris for Thursday, March 7th. Today the Sun will be up for 11 hours and 30 minutes, setting at 6:39, and it will rise tomorrow at 7:06. The Moon, 3 days before new, will rise at 6:35 tomorrow morning.
The constellation of Monoceros the unicorn is located in an area of sky to the left of Orion so it’s in the south at 8 pm, inside the Winter Triangle of stars, Betelgeuse in Orion; Sirius in the Great Dog, Canis Major; and Procyon in Canis Minor. If you don’t see anything there, it’s OK. Nobody sees real unicorns any more anyway. Are there any real unicorns? Anyway, there’s a great number of nebulae here in the Milky Way that runs through it, which unfortunately are too faint to be seen with amateur telescopes. However, it is a gold mine for amateur astronomers who are also astrophotographers using time exposures to record the faint nebulae here, including the famous Rosette Nebula!
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: 03/05/2024 – Finding Gemini the twins
This is Ephemeris for Tuesday, March 5th. Today the Sun will be up for 11 hours and 24 minutes, setting at 6:36, and it will rise tomorrow at 7:10. The Moon, 2 days past last quarter, will rise at 5:22 tomorrow morning.
The constellation of Gemini the twins can be seen high in the south at 8 pm tonight. It’s located above and left of the constellation of Orion. The two brightest stars at the upper left of the constellation have the twin’s names. They are Castor, the one to the upper right and Pollux the brighter one to the lower left. I tend to see the constellation as the two lines of stars from Castor and Pollux running down toward Orion as a silhouette of these two boys standing together. Others see them as two stick figures. At the bottom of the line of stars emanating from Castor, what I consider Castor’s foot, is a lovely star cluster which is visible in binoculars as a little fuzzy spot, but a telescope will show a great number of stars here called Messier 35 or simply M35.
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 