Constellation Chart

The Greater Dog

The master of constellations in winter skies is Orion, and perhaps you'll agree that the master of stars should be alpha Canis Majoris, Sirius. The brightest star in heavens has the magnitude of -1.5, certainly it's no giant at an estimated 1.5 Sun diameters. Its brightness of worthy of special mention comes from the fact that the star is very close to our system at 8.6 light years away. In ancient Egypt, the appearance of Sirius in the eastern dawn sky was considered that indicates a flood of the Nile River, the observation of Sirius was important affair for farmers. The name of Sirius comes from the Greek meaning "scorching", because the ancient Greek had believed that the season of hot summer was caused when the Sun and Sirius lined up. It's surely that the right ascension of Sirius is near to that of the summer solstice.

Star's In Canis Major

Sirius

SIRIUS (Alpha Canis Majoris). From Orion, look south and to the east to find brilliant Sirius, as if one really needs directions to find the brightest star in the sky. Its name comes from the Greek word for "searing" or "scorching," certainly appropriate for a star that shines at the bright end of the "minus-second" (-1.46) magnitude.

Sirius is the luminary of the constellation Canis Major, the Greater Dog, which represents Orion's larger hunting dog, and as such is commonly referred to as the "Dog Star." So great is its prominence that it has two "announcer stars" that from the mid- northern hemisphere rise before it, Procyon and Mirzam. Famed from times long past, the first glimpse of Sirius in dawn announced the rising of the Nile in ancient Egypt. (It no longer does because of precession, the 26,000-year wobble of the Earth's axis.)

Sirius is also part of a large asterism, the Winter Triangle, the other two stars of which are Betelgeuse in Orion and Procyon in the smaller dog, Canis Minor. Because of its brilliance, Sirius is the champion of all "twinklers," the effect caused by variable refraction in the Earth's atmosphere. The star is bright in part because it is indeed rather luminous, 23 times more so than the Sun. Though a "main sequence" "dwarf star" that, like the Sun, shines by hydrogen fusion, it is twice as massive as our star, and as a result is hotter and brighter, its 9400 Kelvin temperature making it quite white.

But it is also bright to us because it is nearby, a mere 8.6 light years away, just double that of the closest star to the Earth, Alpha Centauri. Sirius's greatest claim to fame may be its dim companion. Though at eighth magnitude (8.44), visually some 10,000 times fainter than the bright star we see (which is called "Sirius A"), Sirius B is actually the hotter of the two, a blue-white 27,000 Kelvin. Though typically separated from each other by a few seconds of arc, Sirius B is terribly difficult to see in the glare of Sirius A.

The only way the companion star can be both hot and dim is to be small, smaller than Earth. The two orbit each other with a 50-year period at an average distance of 20 Astronomical Units (the AU the average distance between the Earth and the Sun), the orbital eccentricity carrying it from 31 AU to 8 AU and back again. From the orbit, we find that the little one has about the mass of the Sun. Called a "white dwarf," on the average it packs a metric ton into a cubic centimeter, roughly a sugar cube.

White dwarfs are the end products of ordinary stars like the Sun, tiny remnants that have run out of nuclear fuel. Most are balls of carbon and oxygen whose fates are merely to cool forever. Sirius B itself is the end product of a star that at one time was much more massive and brilliant than Sirius A is today.

M41 (NGC2287)

M41 (NGC2287) is an open cluster easily located 4 degrees south of Sirius, one of the brightest stars in heavens. You'll enjoy the impressive contrast of Sirius's dazzle light and the modest group of faint stars, M41. The cluster is positioned at about the west edge of winter's Milky Way, so you'll be fascinated with uncountable stars surrounding this object.

Galaxy's In Canis Major

NGC 2207

Explanation: Billions of years from now, only one of these two galaxies will remain. Until then, spiral galaxies NGC 2207 and IC 2163 will slowly pull each other apart, creating tides of matter, sheets of shocked gas, lanes of dark dust, bursts of star formation, and streams of cast-away stars.

IC 2163

Astronomers predict that NGC 2207, the larger galaxy on the left, will eventually incorporate IC 2163, the smaller galaxy on the right. In the most recent encounter that peaked 40 million years ago, the smaller galaxy is swinging around counter-clockwise, and is now slightly behind the larger galaxy. The space between stars is so vast that when galaxies collide, the stars in them usually do not collide.

NGC2354

NGC2354 is a medium sized open cluster at the southern Canis Major, about 1.5 degrees east of delta CMa. The cluster has an apparent diameter of 20 arc minutes and a magnitude of 6.5, and it can be easily found by using a noticeable triangle that forms the hind leg of Great Dog as a guide. You can appreciate another small open cluster of NGC2362 only 1.3 degree ENE from NGC2354. This minor one has a size of only 8 arc minutes, so it should be fairly difficult to distinguish the cluster from the normal stars through binoculars. This image has captured the cluster at the upper left-hand side, it's over exposured around nuclei because of its high-dense stellar distribution.

NGC2359

NGC2359 is a small diffused nebula lying about 9 degrees northeast of Sirius. The nebula has a small size of about 10 arc minutes in span, a dimmed shape can be detected by naked eyes through telescopes. Some observers call the nebula "Duck Nebula" from its figure. The nebula consists of two parts of north and south ones, a vast and indistinct northern part forms a head of duck and a deep southern region forms a bill. NGC2359 contains a special star of "Wolf-Rayet star". Only 300 are discovered in the all celestial sphere until now. It's considered that massive stellar atmosphere is spread out in high velocity, and many emission spectrums are observed.

NGC4449

Canis Major (the Larger Dog) is dominated by brilliant Sirius, which lies to the upper left of center. Mirzam is to the right, while much dimmer Mulipein is to the left. The triangle down near the bottom, below Sirius, is composed (clockwise from the lower left) of Aludra, Wezen, and bright Adhara. Omicron-1 lies directly between Wezen and Sirius, while Omicron-2 is just to the right (to the west of) Omicron-1. Sirius is at the southern apex of the Winter Triangle. Canis major lies to the east of Orion, the two here seen in context. M 41 is a fine open cluster

NGC2360

Planetary Destinations In Canis Major

HD HD47536

Parent Star: HD HD47536 (KO III) in the constellation of Canis major is located at a distance of 401.18 Light Years from our Solar system. Co-ordinates are Right Ascension: 06 37 47.6189 & Declination: -32 20 23.045. The apparent Magnitude of the star is 5.261. The Inner Edge of Habitability Zone is 6.06 AU & the Outer Edge of Habitability Zone: 18.88 AU. Orbiting around HD47536 is planet HD47536 b is believed to be a Clarified Jovian and its exitence has been confirmed. The Planets Appearance is a Blue and cloudless. The planet is positioned out side of Habitability Zone at Mean Orbital Distance of 1.61 AU and the planet Orbits around the star every 712.13 ± 0.31 Days and was discovered by SETIAWAN J., HATZES A., von der LUHE O., PASQUINI L. NAEF D., da SILVA L., UDRY S., QUELOZ D. & GIRARDI L in 2002.