Archive
02/01/2016 – Ephemeris – Previewing February
Ephemeris for Monday, February 1st. The Sun will rise at 8:02. It’ll be up for 9 hours and 48 minutes, setting at 5:50. The Moon, 1 day past last quarter, will rise at 2:34 tomorrow morning.
Let’s preview the month of February. It will be a day longer this year because it’s a leap year, the adjustment to keep the calendar in sync with the seasons. The daylight hours throughout February will be getting longer. Daylight hours will increase from 9 hours and 48 minutes today to 11 hours and 8 minutes on the 29th. The altitude of the sun at noon will increase from 28 degrees tomorrow to nearly 38 degrees at month’s end. The straits area will see the sun a degree lower. Local noon, by the way for Interlochen and Traverse City is about 12:56 p.m, which is mainly due to the fact that our standard time meridian happens to run through Philadelphia and the Sun is currently running 13 minutes slow.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addenda
February Star Chart
Star Chart for February 2016. Created using my LookingUp program. To enlarge in Firefox Right-click on image then click View image.
The planets and stars are plotted for the 15th at 9 p.m. EST. That is chart time. Note, Traverse City is located 45 minutes behind our time meridian. To duplicate the star positions on a planisphere you may have to set it to 45 minutes earlier than the current time.
Evening astronomical twilight ends at 6:56 p.m. EST on January 1st, increasing to 7:33 p.m. EST on the 29th.
Morning astronomical twilight starts at 6:56 a.m. EST on January 1st, and decreasing to 6:18 a.m. EST on the 29th.
Add a half hour to the chart time every week before the 15th and subtract and hour for every week after the 15th.
For a list of constellation names to go with the abbreviations click here.
- Pointer stars at the front of the bowl of the Big Dipper point to Polaris the North Star
- A leaky Big Dipper drips on Leo
Calendar of Planetary Events
Credit: Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC)
To generate your own calendar go to http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html
Times are Eastern Time. Some additions made to aid clarity.
Date Local Event Time EST Feb 01 Mo 3:48 am Moon-Mars: 3° S 01 Mo Venus: 31.4° W 03 We 2:05 pm Moon-Saturn: 3.8° S 04 Th 11:34 pm Moon South Dec.: 18.3° S 06 Sa 2:32 am Moon-Venus: 4.5° S 06 Sa 11:47 am Moon-Mercury: 3.9° S 06 Sa 7:59 pm Mercury Greatest Elongation: 25.6° West 08 Mo 9:39 am New Moon 10 We 3:46 pm Moon Descending Node 10 We 9:42 pm Moon Perigee: 364400 km 12 Fr 9:32 pm Mercury-Venus: 4° N 15 Mo 2:46 am First Quarter 16 Tu 2:41 am Moon-Aldebaran: 0.4° S 17 We 6:18 pm Moon North Dec.: 18.3° N 22 Mo 7:48 am Moon-Regulus: 2.7° N 22 Mo 1:20 pm Full Moon 23 Tu 10:58 pm Moon-Jupiter: 1.9° N 24 We 1:10 am Moon Ascending Node 26 Fr 10:28 pm Moon Apogee: 405400 km 28 Su 10:17 am Neptune Solar Conjunction 29 Mo 1:16 pm Moon-Mars: 3.9° S Mar 01 Tu Venus: 24.9° W
Comet C/2013 US10 (Catalina)
The track of Comet C/2013 US10 (Catalina) for February 2016. Created using Cartes du Ciel (Sky Charts).
The comet magnitudes, given after the date, are now pretty much on track. Comet is plotted every day at 10 p.m. EST (3 hr UT the next day). To monitor the brightness reports from observers go to http://www.aerith.net/comet/catalog/2013US10/2013US10.html.
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.
01/28/2016 – Ephemeris – This post has gone to the dogs
Ephemeris for Thursday, January 28th. The Sun will rise at 8:06. It’ll be up for 9 hours and 38 minutes, setting at 5:45. The Moon, 3 days before last quarter, will rise at 10:42 this evening.
The great winter constellation or star group Orion the Hunter, is located in the southern sky at 9:30 p.m. His elongated rectangle of a torso is vertical. In the center of the rectangle are three stars in a line that make his belt. As a hunter, especially one of old, he has two hunting dogs. The larger, Canis Major can be found by following the three belt stars of Orion down and to the left. There lies the brilliant star called Sirius, also known as the Dog Star. It’s in the heart of a stick figure dog facing Orion that appears to be begging. The smaller dog can be found by extending a line through Orion’s shoulder stars to the left. We find a bright star called Procyon. It and one other star make up the hot-dog shaped constellation of Canis Minor, the little dog.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Orion and his hunting dogs revealed in animation. Created with Stellarium and GIMP.
01/25/2016 – Ephemeris – Sirius the Dog Star
Ephemeris for Monday, January 25th. The Sun will rise at 8:09. It’ll be up for 9 hours and 31 minutes, setting at 5:41. The Moon, 2 days past full, will rise at 7:43 this evening.
While we’re waiting for the bright Moon to leave the evening sky, let’s look at another bright star. This one is the brightest of all, Sirius the Dog Star. The Dog Star name comes from its position at the heart of the constellation Canis Major, the great dog of Orion the hunter. The three stars of Orion’s belt tilt to the southeast and point to Sirius. The name Sirius means ‘Dazzling One’, a reference to its great brilliance and twinkling. The Romans thought Sirius added its heat to that of the Sun in summer to bring on the scorching Dog Days of July and August. Its ancient Egyptian name was Sothis, and its first appearance in the morning twilight in late June signaled the flooding of the Nile, and the beginning of the Egyptian agricultural year.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Orion’s Belt points to Sirius. Created using Stellarium.
01/12/2016 – Ephemeris – Down a lazy river to Achernar
Ephemeris for Tuesday, January 12th. The Sun will rise at 8:18. It’ll be up for 9 hours and 5 minutes, setting at 5:24. The Moon, 3 days past new, will set at 8:46 this evening.
There’s a long and sinuous constellation that’s part of the winter sky. It is Eridanus, which depicts a river. The river starts near the lower right corner of Orion, near the bright star Rigel and flows to the right then down near the southern horizon, then it meanders below the horizon. One has to travel to the far southern United States or even farther south to see the southern terminus of the river, the bright star Achernar. Writers over the ages have seen here the Nile and the earth circling river Ocean of the flat earth days. In fiction Star Trek’s Mr. Spock supposedly came from a planet called Vulcan orbiting a star in Eridanus, sometimes identified as 40 Eridani, a dim triple star system 16.5 light years away.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Eridanus with possible homes for Mr. Spock indicated. Created using Cartes du Ciel (Sky Charts).
In the chart above I’ve displayed that Bayer Greek letter designations and the Flamsteed numerical designations for the stars. There’s actually two candidate stars for Spock’s home world Vulcan. Epsilon (ε) is one. I’ve even mentioned it in prior posts. It’s 10.5 light years away. The star itself is 82% the mass of the Sun. It also has one and possibly two planets. The problem is that the star is young, lass than a billion years old. Any planet in the habitable zone of that star would be approximately the same state of development as the Earth 3 1/2 billion years ago.
The second star is 40 Eridani or Omicron 2 (ο2). The star is not labeled on the chart. It’s just above the “40” I marked on the chart. It is a triple star system that’s about 16.5 light years away. The brightest star is 84% the mass of the Sun, cooler, and about half as bright. The nearest of the companion stars comes almost as close as the orbit of Neptune to the primary star. The other one is much farther away. Though no planets have been found, a planet in the habitable zone would have a stable orbit. This star system is about a billion years older than the Sun, so it would be an ideal place to have an advanced civilization. Though the exact location of Vulcan has never been mentioned in any of the Star Trek series or movies, even Gene Roddenberry, the series creator has seemed to accept 40 Eridani as the location for Vulcan.
01/11/2016 – Ephemeris – Gemini, the half-brothers that are twins
Ephemeris for Monday, January 11th. The Sun will rise at 8:18. It’ll be up for 9 hours and 4 minutes, setting at 5:22. The Moon, 2 days past new, will set at 7:36 this evening.
Before the Moon brightens the evening sky, lets look at another of the winter constellations. The constellation Gemini, the Twins is visible high in the east-southeast, above and left of Orion the hunter at 9 p.m. The namesake stars of the two lads, will be at the left end of Gemini, vertically aligned. Castor is on top, while Pollux is below. From them come two lines of stars extending toward Orion that outline the two. In Greek mythology the lads were half brothers, Castor was fathered by a mere mortal, while Pollux was fathered by Zeus in the famous Leda and the swan affair, but were born together. When Castor was killed during the quest for the Golden Fleece, Pollux pleaded with Zeus to let him die also, so both appear together in the sky forever.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Gemini revealed by animation. Created using Stellarium and GIMP.
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.
01/04/2016 – Ephemeris – Some named stars in Orion and how to remember them
Ephemeris for Monday, 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, 2 days past last quarter, will rise at 3:49 tomorrow morning
Now that the Moon has fled let’s turn to the dark skies of winter and the magnificent constellation of Orion the hunter. At 9 p.m. he’s not yet completely upright in the southeast at 9 p.m. His seven bright stars make him easy to spot, starting with his belt of three stars in a straight line angling down to the left. It is inside a rectangle framing his shoulders and knees, leaning now to the left. The bright reddish star at the upper left corner is Betelgeuse, which according to a certain movie one shouldn’t say three-time in a row. The other shoulder star is a name familiar to Harry Potter fans, Bellatrix, though there’s nothing Lestrange about it. The lower right star is the bright blue-white Rigel. All in all a very impressive constellation.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Some of Orion’s star names. Orion at 9 p.m. January 4, 2016. Created using Stellarium.
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.
12/15/2015 – Ephemeris – Procyon the star that’s “Before the dog”
Ephemeris for Tuesday, December 15th. The Sun will rise at 8:13. It’ll be up for 8 hours and 49 minutes, setting at 5:02. The Moon, 3 days before first quarter, will set at 9:48 this evening.
Visible low in the east at 9:30 p.m. appears the star Procyon to its lower left is Sirius the brightest night-time star. Procyon is the bright star in the constellation Canis Minor, or lesser dog. I can find only one other star in Canis Minor. Perhaps it’s a hot dog. If Sirius, in Canis major is the Dog Star then Procyon should be the Little Dog Star. However Procyon is an interesting name. It means “Before the dog”, which is an allusion to the fact that Procyon, though east of Sirius actually rises before it. This is due to Procyon’s more northerly position. This effect doesn’t work south of the equator, however. Sirius will rise at about 9 tonight. Procyon is a star much like Sirius but is 32% farther away. It’s 11.4 to Sirius’ 8.6 light years away.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Procyon, Sirius and the stars of winter. Created using Stellarium
In the above chart, beside the constellation lines, we have the grid of right ascension, from lower left to upper right; and declination, from upper left to lower right. right ascension lines are like longitude on the Earth, while declination lines are latitude lines. They are tipped because I don’t live at either the equator or one of the poles. As the Earth rotates the Sun, stars and planets slide westward in the direction of the declination lines. Note that Sirius is closer to the horizon than Procyon. Also that Sirius is west of the 7 hour right ascension line. (Take my word for it.) Procyon is east of that line, thus Sirius is west of Procyon.
Other cool things can be seen in the chart. Note the declination line that touches the horizon at the east compass point and runs just above Orion’s belt. It is 0º declination, or the celestial equator. It extends to the west compass point on the western horizon. The Sun on the equinoxes will rise due east and set due west. The 6 hour right ascension line runs past Betelgeuse in Orion. At 23½º north declination, near Castor’s big toe in Gemini is where the Sun appears on the first day of summer, the summer solstice.
P.S. It was cloudy and rainy the last two days. Didn’t see a Geminid meteor again this year, keeping my record intact.
Bob Moler's Ephemeris Blog 