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super suns of the heavens
Below the western portion, at a point corresponding with 6 hours on our "dial," is a very bright star which twinkles with many colors. This is Canopus , the second brightest star of the heavens. If we turn to the right to face west, we observe a little to the south-west and close to the horizon the brightest star in all the heavens—Sirius.
Canopus is known to us as Alpha of the Ship Argo, and Sirius is the famous Dog-star, Alpha of the Big Dog. To the aborigines, the former was Waa, the Crow, a very powerful and wise old character; while the latter was the Eagle —possibly they connected the unwavering brilliance of the star with the extra-ordinary keenness of the eagle's eye. These two bright stars are examples of blazing suns much larger and hotter than our own. Although Canopus appears a little less brilliant than Sirius it is thought to be actually very much the brighter. Latest estimates (all astronomical figures are estimates rather than direct measurements) of the distances of these stars from the earth place Sirius about twice as far away as Alpha Centauri, and Canopus at least 50 times as far. If this is so, Sirius must be at least 15 times, and Canopus more than 10,000 times, as bright as the Sun. Some put the latter figure at 100,000, but, so great is the distance, that only a microscopically small portion of the emitted light reaches us.
If the positions of these two stars were reversed, Sirius would be invisible to the . naked eye while Canopus would appear many times brighter than any other heavenly object except the Sun and the Moon. It would be so brilliant that it would cause quite distinct shadows, and its glare would hide the other stars for some distance around it.
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