Archive
02/04/2013 – Ephemeris – The celestial unicorn
Ephemeris for Monday, February 4th. The sun will rise at 7:57. It’ll be up for 9 hours and 58 minutes, setting at 5:56. The moon, 1 day past last quarter, will rise at 3:41 tomorrow morning.
Among all the constellations in the sky of animals real and mythical, there is also a unicorn. It’s called Monoceros, and inhabits the southeastern sky at 9 p.m. bounded by Orion on the right, Canis Major, the great dog below and Canis Minor, the little dog to the left. Unfortunately for observers without optical aid Monoceros, though large, is devoid of any but the faintest stars. Maybe that’s why no one sees unicorns anymore. It has many faint stars because the Milky Way runs through it. To the telescope it is a feast of faint nebulae or clouds of gas and dust, the birth place of stars, including the red rose of the Rosette Nebula, and the strange and tiny Hubble’s Variable Nebula. It has a wealth of wonders below the surface so to speak.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Moniceros the unicorn. Created using Stellarium.
01/22/2013 – Ephemeris – Sirius the Dog Star
Ephemeris for Tuesday, January 22nd. The sun will rise at 8:10. It’ll be up for 9 hours and 27 minutes, setting at 5:37. The moon, half way from first quarter to full, will set at 5:23 tomorrow morning.
The brightest star-like object in the evening sky is Jupiter high in the sky now. The second brightest star-like object is Sirius, also known as the Dog Star. It also is the brightest night-time star in our skies period. Tonight at 9 p.m. it’s located low in the southeastern sky. 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’ or ‘Scorcher’, a reference to its great brilliance and twinkling. Its Egyptian name was Sothis, and its appearance in the dawn skies 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
Winter Circle and Jupiter with Sirius at the bottom. Created using Stellarium.
01/11/2013 – Ephemeris – Sirius the Dog Star
Ephemeris for Friday, January 11th. The sun will rise at 8:17. It’ll be up for 9 hours and 6 minutes, setting at 5:23. The moon is new today, and won’t be visible.
The brightest star-like object in the evening sky is Jupiter high in the south around 9 p.m. The second brightest star-like object is Sirius, also known as the Dog Star. It also is the brightest night-time star in our skies period. Tonight at 9 p.m. it’s located low in the south southeastern sky. 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. Its Egyptian name was Sothis, and its appearance in the dawn skies 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
Sirius, Jupiter and the winter stars and constellations at 9 p.m. Created using Stellarium.
01/27/2012 – Ephemeris – The constellation Canis Major
Ephemeris for Friday, January 27th. The sun will rise at 8:07. It’ll be up for 9 hours and 36 minutes, setting at 5:43. The moon, 3 days before first quarter, will set at 10:49 this evening.
What kind of a hunter would the constellation Orion be without his trusty hunting dogs. The larger of the dogs is Canis Major which can be found if you extend Orion’s belt stars down to the left. There in the south southeast will appear the brightest night time star Sirius the Dog Star. It is in the heart of the dog, which appears to be begging. Well it’s tilted funny. Other than that it’s a pretty good representation of a dog as a stick figure. The name Sirius doesn’t mean Dog Star, but means Dazzling One due to its great brightness. It outshines all other night stars, only to be out shown by the planets Venus, Jupiter and occasionally Mars. Binoculars will show a nice little star cluster a short ways below Sirius known as M41.
* Times, as always are for the Traverse City/Interlochen area of Michigan.
Addendum
Orion and his Hunting Dogs. Created using Stellarium.
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.
04/26/11 – Ephemeris – Last chance to spot the winter constellations
Tuesday, April 26th. The sun rises at 6:40. It’ll be up for 13 hours and 59 minutes, setting at 8:40. The moon, 2 days past last quarter, will rise at 3:56 tomorrow morning
Lets face it we’re pretty sick of winter, what with all the relapses this month. But I’m never sick of the winter stars and constellations. With Leo and the other spring constellations taking over the skies from overhead to the south, the winter constellations are about to set in the west at 10 p.m. Orion’s rectangular torso is tipped to the right, his belt stars horizontal, 90 degrees from their rising orientation. The same is true of Castor and Pollux higher up which rose vertically and will set horizontally. The brightness and closeness of the stars here are a great contrast with the sparse numbers of stars visible overhead and to the south. That’s because the Milky Way runs through the winter stars and crosses to the north part of the sky.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Winter Stars Setting in Late April. Created using Stellarium.
Bob Moler's Ephemeris Blog 