Archive
Ephemeris: 05/28/2024 – Finding Spica and Virgo
This is Ephemeris for Tuesday, May 28th. Today the Sun will be up for 15 hours and 15 minutes, setting at 9:18, and it will rise tomorrow at 6:01. The Moon, 2 days before last quarter, will rise at 2:06 tomorrow morning.
The Big Dipper, near the zenith at 10:30 pm points to several stars and constellations. It’s handle points to two bright stars. First we follow the arc of the handle to the bright orange star Arcturus, the 4th brightest nighttime star. The reason I say nighttime is that the Sun is a star also, but by definition is not out at night. The arc to Arcturus is a way to find Arcturus and a clue to its name. Arcturus, high in the south-southeast, lies at the base point of the kite shaped constellation of Boötes the herdsman. From Arcturus, straighten out the arc to a spike and one soon arrives at Spica a blue-white star in Virgo the virgin, now in the south. Spica is also sometimes pronounced ‘Speeka’.
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: 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: 05/09/2024 – How the Great Bear got her long tail
This is Ephemeris for Thursday, May 9th. Today the Sun will be up for 14 hours and 37 minutes, setting at 8:58, and it will rise tomorrow at 6:19. The Moon, 2 days past new, will set at 11:30 this evening.
As we see the Great Bear, Ursa Major in the sky with the Big Dipper as its hind end and tail, it seems apparent that the bear is unusual, because bears don’t have long tails. The peoples of the old world, Greeks and others, had a story of how the bear got his long tail. The God Zeus was responsible for the predicament that caused a young lady to be turned into the bear and placed her in the sky out of harm. Some question how he did this. To throw her into the sky, he probably didn’t want to grab the end with the teeth, so he grabbed the bear’s stubby tail whirled the bear around his head and threw her up into the sky where we see her today. Of course the tail was stretched. Some Native Americans did see a bear here too. But the three stars of the dipper’s handle were 3 hunters following the bear.
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
For the story of why the young lady, Callisto, was turned into a bear, check out this post of a week ago: https://bobmoler.wordpress.com/2024/05/02/…
Ephemeris: 05/07/2024 – Coma Berenices, a queen’s sacrifice
This is Ephemeris for Tuesday, May 7th. Today the Sun will be up for 14 hours and 32 minutes, setting at 8:55, and it will rise tomorrow at 6:22. The Moon is new today, and won’t be visible.
High in the south-southeast at 10:30 p.m. is a tiny and faint constellation of Coma Berenices, or Berenice’s Hair. In it are lots of faint stars arrayed to look like several strands of hair to the naked eye. The whole group will fit in the field of a pair of binoculars, which will also show many more stars. The story behind it was that Berenice was a real queen of Egypt, whose husband, the Pharaoh Ptolemy III, was away at war. This was in the days when the Greeks ruled Egypt after Alexander had conquered it. She offered her golden tresses to the gods for the king’s safe return. The hair, was placed in a temple. However, the offering disappeared when the king returned. Ever since then, the constellation of Coma Berenices has been seen to commemorate the queen’s sacrifice.
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
Do not confuse the Coma Berenices star cluster (Melotte 111 and Collinder 256) with the Coma Cluster (actually a supercluster of galaxies up to 300 million light years away) in the northern part of the constellation. The Coma Cluster contains upwards of 10,000 galaxies.
Ephemeris: 05/02/2024 – All about the constellation of Boötes and Ursa Major
This is Ephemeris for Thursday, May 2nd. Today the Sun will be up for 14 hours and 19 minutes, setting at 8:49, and it will rise tomorrow at 6:29. The Moon, 1 day past last quarter, will rise at 4:27 tomorrow morning.
Seen in the east at 10:30 p.m. tonight is the kite shaped constellation of Boötes the herdsman. The bright star Arcturus is at the bottom of the kite to the right. It is pointed to by the arc of the handle of the Big Dipper, higher in the east. Boötes represents a young hunter named Arcas, son of Callisto, a beautiful young lady who had the misfortune of being loved by Zeus the chief of the Greek gods. Zeus’ wife Hera, found out about it, and since she couldn’t punish Zeus, turned the poor woman into a bear. Arcas, many years later, unaware of the events surrounding his mother’s disappearance was about to kill the bear when Zeus intervened and placed them both in the sky to save her, as Arcas still pursues her across the sky nightly.
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: 04/29/2024 – Corona Borealis, the Northern Crown
This is Ephemeris for Monday, April 29th. Today the Sun will be up for 14 hours and 11 minutes, setting at 8:46, and it will rise tomorrow at 6:33. The Moon, 2 days before last quarter, will rise at 2:58 tomorrow morning.
About a third of the way up the sky in the east at 10 p.m. can be found a small but easily spotted constellation of Corona Borealis, the Northern Crown. It is located just below the kite shaped constellation of Boötes, with its bright star Arcturus at the right. The Northern Crown is a three-quarter circle of stars, like a tiara, with a brighter star Alphecca at the bottom. Alphecca in Arabic means “The bright star of the broken ring of stars”, which is an accurate description of it. Check it out now for later this year we expect to have a bright star appear just below it. That star is T Coronae Borealis a recurrent Nova or exploding star. They occur when a white dwarf star is orbiting with a large red giant star and accumulating gas from that red giant star until it explodes.
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: 04/25/2024 – Finding Hydra, the longest constellation
This is Ephemeris for Thursday, April 25th. Today the Sun will be up for 14 hours exactly, setting at 8:41, and it will rise tomorrow at 6:39. The Moon, 2 days past full, will rise at 11:00 this evening.
Stretching from midway up the sky in the southwest to low in the southeast at 10 p.m. can be found the constellation of Hydra the water snake, the longest constellation of all. Unlike the monster of the same name that Hercules slew, this Hydra has but one head, which is its most distinctive part. The head of Hydra is located between the bright stars Procyon in the southwest. Which is above the brighter star Sirius low in the sky, and Regulus in Leo the lion, higher in the south. Hydra’s head is a small but distinctive group of 6 stars that make a drooping loop to the right. The rest of Hydra wends its way in a reasonably straight line down to the southeastern horizon.
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: 03/26/2024 – The dimmest constellation of the Zodiac is Cancer the crab
This is Ephemeris for Tuesday, March 26th. Today the Sun will be up for 12 hours and 29 minutes, setting at 8:03, and it will rise tomorrow at 7:31. The Moon, 1 day past full, will rise at 9:44 this evening.
The dimmest constellation of the Zodiac is Cancer the crab. It is located high in the southeast at 9 PM between the backwards question mark that is the front of Leo the lion towards the lower left and Castor and Pollux of Gemini to the upper right. Its claim to more modern astronomical fame is the star cluster within it called the Beehive Cluster also known in ancient times as Praesepe the manger which looks like a fuzzy spot to the naked eye. In binoculars or a small telescope it shows up as a rather sparse open cluster of stars and to me the whole cluster appears somewhat triangular like an old-fashioned beehive. The Beehive cluster is relatively close to us at about 610 light years away.
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
Bob Moler's Ephemeris Blog 