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Canis Major - The Great Dog
Evrey hunter needs hunting dogs as companions and the Great Hunter Orion is no exception. Orion has two dogs as companions, Canis Major (the Great Dog) and Canis Minor (the lesser dog). Both of these faithful companions sit at the feet of Orion waiting for their next expedition.
In addition to being one of the companions of Orion, Canis Major is also the stellar home of Sirius, which is the brightest star in the night sky. When Canis Major is visible, the brilliant white light of Sirius shines like a searchlight in the sky. Although Sirius is not a very large star, being only about one and one-half times as large as our own Sun, its young age and relatively close distance combine to make it so bright.

When Can I see Canis Major?
Since Canis Major is located so close to Orion, you can see this constellation almost any time that Orion is visible. This means that the Great Dog is visible in the morning hours during the fall and in the evening during winter. Look below and to the left of Orion to find the bright light of Sirius. After you have located Sirius, find the rest of the bright stars in this constellation will be very easy.

The "Dog Days" of Summer
No doubt you have often heard the phrase "dog days of summer" used to describe the hottest part of the summer season. This phrase originated with the ancient Egyptians and Romans. The brightness of Sirius led them to believe that when Sirius was in conjuction with the Sun, that the heat of the Sun was increased by the heat of Sirius, leading to very uncomfortable conditions. We have since learned that the Sun produces all the heat without any outside aid, but it does make for an interesting story.

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