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Canis Major, the Great Dog, is visible during the winter months in the Northern Hemisphere.
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Canis Major

Canis Major is known as the Great Dog. In Greek myth, it is said that this constellation, along with Canis Minor, are Orion's hunting dogs. Canis Major was one of the most important constellations in ancient times because the brightest star in the sky is part of it.

Sirius, the Dog Star, is one of the brightest objects in the night sky. Only the Moon, Venus, Jupiter and Mars are brighter. Those that lived near the Nile River used the star to signal the flooding of the Nile. This special occasion represented the return from the dead of the Sun god Osiris.

Canis Major is very easy to find during the months of November through March. First locate Orion the Hunter, and imagine a straight line through his belt. Follow the line to the southeast, and you will see Sirius perched right below it. Sirius is the nose of the dog. His body stretches to the southeast, and his front leg is to the west of Sirius.

Not only is Sirius bright, but it is also mysterious. Ancient civilizations described the star as red and fiery, but today it is very white. Scientists can't explain this phenomenon. With the exception of Sirius, Canis Major doesn't contain any significant stellar objects. M41 is an open cluster just south of Sirius; it is visible on clear nights. There are a few nebulae and galaxies, but they are too faint to see even with a small telescope.

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