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12/27/2013 – Ephemeris – The star Procyon: “Before the Dog”
Ephemeris for Friday, December 27th. The sun will rise at 8:18. It’ll be up for 8 hours and 50 minutes, setting at 5:08. The moon, 2 days past last quarter, will rise at 3:48 tomorrow morning.
Yesterday I talked about the brilliant star Sirius, the dog star pointed to by the stars of the belt of Orion. Today we’ll look at another dog star. Procyon, the bright star in Canis Minor, the lesser dog. It is pointed to by the top two stars in the Orion rectangle Bellatrix and Betelgeuse. One of the translations of Procyon means “Before the Dog”. This seemingly odd title is explained that even though Procyon is east of Sirius and all things being equal, well at least latitude or declination the eastern star should rise after the western star. However Procyon is north of Sirius and if one is sufficiently north of the equator, the eastern most star can rise first. This is what happens. Procyon is a bit farther away than Sirius and isn’t quite as bright either.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Procyon is already up as Sirius rises. Procyon also sets after Sirius. Created using Stellarium.
Note: Stellarium approximates atmospheric extinction, that is dims objects when they are near the horizon an effect due to looking through more of the Earth’s atmosphere when looking close to the horizon. That’s why Sirius looks rather fainter than in yesterday’s image.
03/04/2013 – Ephemeris – The Winter Circle
Ephemeris for Monday, March 4th. The sun will rise at 7:14. It’ll be up for 11 hours and 20 minutes, setting at 6:34. The moon, at last quarter today, will rise at 2:34 tomorrow morning.
The winter skies are blessed with more first magnitude stars than any other season. 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 and downward, we come to Aldebaran in the face of Taurus the Bull and brighter nearby Jupiter. 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 Orion’s other hunting dog, Then above 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 and Jupiter for March. Created using Stellarium.
01/29/2013 – Ephemeris – Procyon, the Little Dog Star
Ephemeris for Tuesday, January 29th. The sun will rise at 8:04. It’ll be up for 9 hours and 43 minutes, setting at 5:47. The moon, 3 days past full, will rise at 8:52 this evening.
The constellation Orion has two hunting dogs. We’ve seen Canis Major the greater dog at Orion’s feet with Sirius in its heart. The lesser dog, Canis Minor iS level with Betelgeuse in Orion’s shoulder and off to the left. Just two stars mark it. Is it a dachshund or maybe a hot dog? It’s brighter star’s name is Procyon which means “Before the dog”, an odd title. It means that though east of Sirius, it rises before Sirius, due to its more northerly position in the sky. In many ways Procyon is nearly a twin of Sirius. It shines with the same white color, although a bit cooler, and has a white dwarf companion like Sirius. It’s a bit farther away than Sirius 8 light years. Procyon is at a distance of 11.46 light years. Procyon, Betelgeuse and Sirius make the winter triangle.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Winter Circle and Jupiter with Procyon to the far left. Created using Stellarium.
02/20/2012 – Ephemeris – The Winter Circle
Ephemeris for President’s Day, Monday, February 20th. The sun will rise at 7:35. It’ll be up for 10 hours and 41 minutes, setting at 6:17. The moon, 1 day before new, will rise at 7:01 tomorrow morning. | The winter skies are blessed with more first magnitude stars than any other season. Six of these stars lie in a large circle centered on the seventh. This circle is up at 9 p.m. Starting high overhead is Capella in Auriga the charioteer. Moving down clockwise is 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, lowest of these stars in the south southeast. Moving up and left is Procyon in Canis Minor, Above Procyon is Pollux in Gemini the twins. All these are centered on Betelgeuse the bright red star in Orion’s shoulder.
* 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
12/20/11 – Ephemeris – Procyon, the “Little Dog Star”
Tuesday, December 20th. The sun will rise at 8:15. It’ll be up for 8 hours and 48 minutes, setting at 5:04. The moon, 3 days past last quarter, will rise at 4:45 tomorrow morning.
Visible low in the east at 9 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. Procyon is a star much like Sirius but farther away. [It’s 11.41 to Sirius’ 8.6 light years away. And like Sirius it even has a small white dwarf star in its system.]
* Times, as always are for the Traverse City/Interlochen area of Michigan. Text in brackets was omitted in the audio program due to time constraints.
Addendum
Procyon, Sirius and the stars of winter. Created using Stellarium
The grid lines are right ascension and declination, analogous to longitude and latitude on the earth. Looking eastward the right ascension lined run from the upper left to the lower right. Thus Procyon is definitely farther east than Sirius.
Bob Moler's Ephemeris Blog 