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11/06/2017 – Ephemeris – Taurus’ angry red eye, Aldebaran
Ephemeris for Monday, November 6th. The Sun will rise at 7:27. It’ll be up for 9 hours and 57 minutes, setting at 5:24. The Moon, 3 days past full, will rise at 7:52 this evening.
Last night the Moon passed in front of or occulted the bright star Aldebaran. Above right of Moon tonight is Aldebaran the bright orange star with a V shape of other stars in the face of Taurus the bull. Aldebaran appears at the lower left tip of that letter V laying on it’s side. With the bright Moon, it might take binoculars to pull out the faint stars of the V. Aldebaran isn’t actually part of the group, called the Hyades star cluster. The cluster is about 153 light years away, while Aldebaran is 65 light years away. The star has an orange hue because its surface is cooler than the Sun’s. However Aldebaran is 44 times larger in diameter, and shines 425 times brighter than the Sun. The name Aldebaran means “Follower” because it follows the Pleiades star cluster above it.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Aldebaran in the Hyades (unlabeled), with also the Pleiades, unlabeled, at the top and the Moon. at 9 p.m., November 6, 2017. Created using Stellarium.
09/12/2017 – Ephemeris – The Moon will hide the bright star Aldebaran after sunrise this morning
Ephemeris for Tuesday, September 12th. The Sun will rise at 7:18. It’ll be up for 12 hours and 40 minutes, setting at 7:58. The Moon, 1 day before last quarter, will rise at 12:13 tomorrow morning.
This morning during daylight at around 8:40*. the bright star Aldebaran will disappear behind the Moon. Binoculars or a small telescope can be used to spot Aldebaran, the bright star in the constellation Taurus the bull’s eye. Taurus and the rest of the winter constellations are visible before sunrise. The sky needs to be absolutely clear to be able to spot the event. The star will be seen to approach the bright side of the Moon. The star will reappear around 9:53 a.m.* on the dark western edge of the Moon. These events are called occultations. They come from the word occult, which means hidden. In actuality the solar eclipse of three weeks ago was a spacial case of an occultation for those in the path of totality.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
* The disappearance and appearance times for Aldebaran are within a couple of minutes for Western Michigan. For other locations in the occultation path Stellarium will give pretty good times for the events by modeling the occultation as I did below. Like a solar eclipse where you are determines the timing of the event.
Addendum
Map of where the occultation is visible. For the area bounded in red, the occultation is visible in the daytime. Credit: Occult4 by IOTA.
Position of the Moon in the sky near the start of the occultation, 8:35 a.m. September 12, 2017. Created using Stellarium.
Aldebaran and the Moon at 8:35 a.m. September 12, 2017. Created using Stellarium.
Aldebaran reappearing from behind the Moon at 9:53 a.m. September 12, 2017. Created using Stellarium.
02/16/2017 – Ephemeris – The Winter Circle
Ephemeris for Thursday, February 16th. The Sun will rise at 7:40. It’ll be up for 10 hours and 32 minutes, setting at 6:12. The Moon, 2 days before last quarter, will rise at 12:17 tomorrow morning.
The winter skies are blessed with more first magnitude stars than any other season. These are the twenty-one brightest stars in the sky. Six of these stars lie in a large circle centered on the seventh. This circle is up all evening now that we are in the heart of winter. Starting high overhead is Capella in Auriga the charioteer. Moving clockwise, we come to Aldebaran in the face of Taurus the Bull. Then down to Orion’s knee we find Rigel. Down and left is the brightest star of all Sirius the Dog Star in Canis Major Orion’s large hunting dog, lowest of these stars in the south. Moving up and left there is Procyon in Canis Minor, Then above it is Pollux in Gemini the twins. All are centered on Betelgeuse in Orion.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Winter Circle of 1st magnitude stars. Created using my LookingUp program.
01/23/2017 – Ephemeris – The rabbit that got away
Ephemeris for Monday, January 23rd. The Sun will rise at 8:10. It’ll be up for 9 hours and 29 minutes, setting at 5:39. The Moon, half way from last quarter to new, will rise at 5:17 tomorrow morning.
Orion, the central winter constellation is seen in the south-southeast at 9 p.m. He is a hunter, but is preoccupied in defending himself from the charge of Taurus the bull to the upper right. At Orion’s feet, and unnoticed by him is the small constellation of Lepus the hare. It’s very hard to see a whole rabbit in its eight dim stars: however, I do see a rabbit’s head, ears and shoulders. A misshapen box is the head and face of this critter facing to the left. His ears extend upwards from the upper right star of the box, and the bend forward a bit. Two stars to the right of the box and a bit farther apart show the front part of the body. The free computer program at Stellarium.org shows a whole rabbit facing the opposite direction.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
An animation showing the stars, constellations and artwork of Lepus, Orion and Taurus. Created using Stellarium and GIMP.
12/12/2016 – Ephemeris – The Moon will cover the eye of the bull tonight
Ephemeris for Monday, December 12th. The Sun will rise at 8:11. It’ll be up for 8 hours and 51 minutes, setting at 5:02. The Moon, 1 day before full, will set at 7:21 tomorrow morning.
Late tonight the nearly full moon will pass in front of the bright star Aldebaran. This will be a difficult event to spot due to the brightness of the Moon. It will take a telescope at least to spot Aldebaran, the bright star the is the bloodshot eye in the face of Taurus the bull. It might help to spot Aldebaran an hour or two early, while it’s some distance left of the Moon. Aldebaran will disappear at the Moon’s left edge, while its a tiny distance from the bright edge of the Moon at around 10:54 p.m. Aldebaran will reappear at about 12:09 a.m. Make sure to start observing several minutes early since these are low precision times, plus your location affects the times. These times are most accurate in the Western Lower Peninsula of Michigan.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon moves from west to east, so the occultation events will happen earlier to the west and later to the east. Planetarium programs can be used to simulate the position of the Moon and stars and can be used to estimate the occultation start and end times. To be accurate your location longitude and latitude must be entered in the program.
The times I developed are from the free program Cartes du Ciel and are within a minute of that provided by the more accurate program Occult4, which can be downloaded for free at the site below. Planetarium programs are close enough, however. Occult4 is somewhat difficult to use.
If you’re out keep a look out for some bright Geminid Meteors. Their shower will reach its peak tomorrow night.
Start of the occultation at 11:54 p.m EST December 12, 2016. The grid is altitude and azimuth. Created using Cartes du Ciel.
End of the occultation at 12:09 a.m EST December 13, 2016. The grid is altitude and azimuth. Created using Cartes du Ciel.
Path of the occultation. Locations between the bright boundaries would see the occultation at night. Created by the software program Occult4 by the International Occultation Timing Association.
An animation created by Occult4 of the occultation of Aldebaran and some of the dimmer stars of the Hyades.
Eclipse and occultation information and software can be accessed at http://occultations.org/ the website of IOTA, the International Occultation Timing association.
11/28/2016 – Ephemeris – The Hyades the star cluster in the face of Taurus the bull
Ephemeris for Monday, November 28th. The Sun will rise at 7:57. It’ll be up for 9 hours and 7 minutes, setting at 5:04. The Moon, 1 day before new, will rise at 7:45 tomorrow morning.
Rising in the east now is the bright star Aldebaran an orange star that’s at one end of the sideways letter V of stars that is the head of Taurus the bull. Above it is the jewel-like Pleiades or Seven Sisters star cluster. There’s more to Taurus, like it’s freakishly long horns and front part of its body. But you can say you’ve seem Taurus, if you can spot his face. That V of stars is actually a star cluster called the Hyades, and in Greek Myth were the half-sisters of the Pleiades, also fathered by the god Atlas. Both the Hyades and Pleiades are being pursued by Orion, which as Robert Frost put it is throwing a leg over the eastern horizon at 8 to 9 pm. He isn’t the only one following the Pleiades, the name Aldebaran means “The Follower”.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
An animation showing the Hyades, Taurus, Orion and the Pleiades. Created using Stellarium and GIMP. Click on image to enlarge.
Closeup of the Hyades and the Pleiades. Created using Stellarium.
01/29/2016 – Ephemeris – The rabbit that got away
Ephemeris for Friday, January 29th. The Sun will rise at 8:05. It’ll be up for 9 hours and 40 minutes, setting at 5:46. The Moon, 2 days before last quarter, will rise at 11:40 this evening.
Orion, the central winter constellation is seen in the south at 9 p.m. He is a hunter, but he’s preoccupied with the charge of Taurus the bull from the upper right. At Orion’s feet, and unnoticed by him is the small constellation of Lepus the hare. It’s very hard to see a rabbit in its eight dim stars: however, I do see a rabbit’s head ears and shoulders. A misshapen box is the head and face of this critter facing to the left. His ears extend upwards from the upper right star of the box, and the bend forward a bit. Two stars to the right of the box and a bit farther apart hint at the front part of the body. In Lepus telescopes can find M79, a distant globular star cluster, one of the few of these compact clusters visible in the winter sky.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
An animation showing the stars, constellations and artwork of Lepus, Orion and Taurus. Created using Stellarium and GIMP.
As you can see, the image above of Lepus isn’t how I imagine the hare as I mentioned in the text.
01/07/2016 – Ephemeris – The Orion entourage
Ephemeris for Thursday, January 7th. The Sun will rise at 8:19. It’ll be up for 8 hours and 59 minutes, setting at 5:18. The Moon, 2 days before new, will rise at 6:42 tomorrow morning.
The whole Orion entourage is now visible in the southeast at 9 p.m. Orion the hunter with stars at his shoulders and knees and has a belt of three stars in a straight line. He has one arm upraised holding a club from the reddish star Betelgeuse and in the other arm he’s holding a lion skin shield fending off an attack from Taurus the bull above and right of him. Following the belt stars to the lower left we come to the brightest night-time star Sirius the Dog Star in the heart of Canis Major, his great hunting dog. Making a nearly equilateral triangle with Sirius and Betelgeuse is Procyon the little dog star in Canis Minor, Orion’s other small hunting dog. Hunched at the distracted Orion’s feet is the small constellation of Lepus the hare.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Orion Entourage as seen at 9 p.m. January 7, 2016. Created using Stellarium
Orion and the head of Taurus photograph by myself January 4, 2016 at 11:30 p.m. It’s a stack of 5 untracked 20 second exposures.
Limiting magnitude is about 8, so you’re seeing stars you’d see with binoculars. The glow off to the left s from Traverse City, the center of which is 6 miles away to my northeast. I’m looking south here to get out of the glow, so Orion is more upright. I didn’t quite make it. My southwest through northwest is the darkest.
As you can probably guess I’ve got a new camera for my birthday/Christmas, a Canon EOS Rebel T5, and I’m investigating its astrophotographic capabilities. So expect some more “new” actual photographs on these posts.
12/17/2015 – Ephemeris – The bright star Aldebaran the “follower”
Ephemeris for Thursday, December 17th. The Sun will rise at 8:14. It’ll be up for 8 hours and 48 minutes, setting at 5:03. The Moon, 1 day before first quarter, will set at 12:07 tomorrow morning.
The central constellation of winter Orion, will be rising the east-southeast at 9 p.m. Above it is Taurus the bull. The bright orange star in Taurus is Aldebaran. Aldebaran appears at the lower left tip of a letter V group of stars that is the face of the bull. Aldebaran isn’t actually part of the group, called the Hyades star cluster. The cluster is about 151 light years away, while Aldebaran is 65. The star has an orange hue because its surface is cooler than the sun’s. However Aldebaran is 44 times larger in diameter, and shines 425 times brighter than the sun, if you include the infrared which our eyes can’t detect, or 150 times brighter in visible light. The name Aldebaran means “Follower” because it follows the Pleiades star cluster above through the night.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Aldebaran, the Hyades and Pleiades star clusters. Created using Stellarium.
Three views of Taurus the bull and Orion the hunter for 9 p.m. on December 8, 2015. Created using Stellarium and GIMP.
12/10/2015 – Ephemeris – What’s a charioteer doing holding goats?
Ephemeris for Thursday, December 10th. The Sun will rise at 8:08. It’ll be up for 8 hours and 53 minutes, setting at 5:02. The Moon, 1 day before new, will rise at 7:59 tomorrow morning.
Rising now more than half way up the sky in the east at 9 p.m. will be the bright star Capella and its pentagonal constellation Auriga the Charioteer. Auriga appears to be hunched down sideways in the sky in his chariot carrying 4 goats. Capella is the mother goat, and a slim triangle of stars near her are her kids. Perhaps the kids in the chariot were such a distraction that he crashed. So maybe the gods placed them in the sky as a warning. In fact that triangle is an asterism widely known as the Kids. The Milky Way runs through Auriga and it is the home of several star clusters that appear as fuzzy spots in binoculars. Capella for us in northern Michigan never sets. It is a winter star that can be seen year round. It’s disconcerting to spot it scraping the northern horizon in July.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Auriga and neighboring constellations for 9 p.m. December 10, 2015. Created using Stellarium and GIMP.
Bob Moler's Ephemeris Blog 