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Posts Tagged ‘Canis Minor’

03/23/2017 – Ephemeris – a single headed Hydra

March 23, 2017 Comments off

Ephemeris for Thursday, March 23rd.  The Sun will rise at 7:39.  It’ll be up for 12 hours and 19 minutes, setting at 7:59.  The Moon, 3 days past last quarter, will rise at 5:48 tomorrow morning.

In the southern evening sky can be found the constellation of Hydra the water snake.  Unlike the mythical monster Hercules fought of the same name this Hydra has but one head, which is its most distinctive part.  At 9 p.m. look to the south.  The head of Hydra is located directly to the left of Procyon the bright star in Orion’s little dog Canis Minor, and to the right of the star Regulus in Leo.  Hydra’s head is a small distinctive group of 6 stars that make a loop and the snake’s slightly drooping head.  At that time the sinuous body of Hydra sinks below the horizon in the southeast.  As it gets later in the evening the rest of Hydra’s body will slither to just above the southeastern horizon below the planet Jupiter this year and the bright star Spica in the constellation of Virgo.

Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Hydra

Finding Hydra animation for 9 p.m. March 23rd 2017. Created using Stellarium.  Click on image to enlarge.

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02/16/2017 – Ephemeris – The Winter Circle

February 16, 2017 Comments off

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

The Winter Circle of 1st magnitude stars. Created using my LookingUp program.

01/26/2017 – Ephemeris – Is it a dachshund or a hot dog?

January 26, 2017 Comments off

Ephemeris for Thursday, January 26th.  The Sun will rise at 8:07.  It’ll be up for 9 hours and 36 minutes, setting at 5:43.  The Moon, 1 day before new, will rise at 7:40 tomorrow morning.

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 is it a hot dog?  You decide.  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 11 and a half light years away.  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

Orion and hunting dogs

Procyon and Orion’s hunting dogs animation also showing the Winter Triangle asterism*. Created using Stellarium and GIMP.

* Asterism – an informal constellation like the Big Dipper, the Northern Cross, or the Summer Triangle.  Not one of the 88 official constellations.

02/16/2015 – Ephemeris – The little Dog Star

February 16, 2016 Comments off

Ephemeris for Tuesday, February 16th.  The Sun will rise at 7:42.  It’ll be up for 10 hours and 29 minutes, setting at 6:12.   The Moon, 1 day past first quarter, will set at 3:45 tomorrow morning.

Procyon is  the bright star to the east or left of Betelgeuse in the sky tonight, which puts it in the east-southeast at 9 tonight.  Procyon is the brightest of the two stars in Canis Minor, Orion’s little hunting dog.  Procyon is sometimes called the Little Dog Star for that reason.  The Dog Star Sirius is a ways below and right of it.  The name Procyon means “Before the Dog”, because Procyon, though east of Sirius, rises before it due to its more northerly position.  This only works if one is north of 30 degrees north latitude.  South of that, Sirius rises first.  Procyon is a white star 11 and a half light years away, 3 light years farther than Sirius, and like Sirius it has a faint white dwarf companion.  It’s a bit less than half the Sun’s age.

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

Procyon, Sirius and the stars of winter. Created using Stellarium

Note that at their rising Procyon is higher in the sky than Sirius.

There are some grid lines on the chart.  The ones running from lower left to upper right are lines of declination, which are like latitude lines on the Earth.  On this chart they are 10º apart.  The line that intersects the horizon at the east compass point is the celestial equator.  It will meet the western compass point at the horizon.  As the Earth rotates the stars and planets will move westward in the direction of these declination lines.  The lines that run from upper left to lower right are hour lines of right ascension.  Here they are 15 degrees or one hour apart,  The Earth rotates 360º in a sidereal* day.  360 divided by 24 hours gives 15º an hour.  So the celestial sphere of stars and planets will slide 15º westward in a sidereal hour.

*  A sidereal day, rotation with respect to the stars, is about 4 minutes shorter that the solar day, the day and time we keep based on the Sun.  The Sun moves about one degree eastward each day, so the rotation has to catch up that one degree each day.  The rotation of one degree takes 4 minutes.  I’ll let you work that one out for yourself.

02/08/2016 – Ephemeris – The celestial unicorn

February 8, 2016 Comments off

Ephemeris for Monday, February 8th.  The Sun will rise at 7:53.  It’ll be up for 10 hours and 6 minutes, setting at 6:00.  The Moon is new today, and won’t be visible.

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 bright 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 whose central star cluster can be seen in a telescope but the nebulosity requires a camera to capture and store its light.

Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Moniceros the unicorn. Created using Stellarium.

Monoceros the unicorn. Created using Stellarium.

Rosette Nebula

Rosette Nebula in the infrared from the Spitzer Space Telescope. Credit: NASA/JPL/Caltech

01/28/2016 – Ephemeris – This post has gone to the dogs

January 28, 2016 Comments off

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

Orion and his hunting dogs revealed in animation. Created with Stellarium and GIMP.

01/07/2016 – Ephemeris – The Orion entourage

January 7, 2016 Comments off

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

Orion Entourage

The Orion Entourage as seen at 9 p.m. January 7, 2016. Created using Stellarium

Orion photograph

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.