This region is altogether one of the most brilliant in the entire firmament. We must no longer postpone our homage to the brightest star in the sky, the magnificent Sirius, which shines on the left below Orion: it returns every year toward the end of November. This marvelous star, of dazzling brilliancy, is the first, α, in the constellation of the Great Dog, which forms a quadrilateral, the base of which is adjacent to a triangle erected from the horizon.
When astronomers first endeavored to determine the distance of the stars, Sirius, which attracted all eyes to its burning fires, was the particular object of attention. After long observation, they succeeded in determining its distance as 92 trillion kilometers (57 trillion miles). Light, that radiates through space at a velocity of 300,000 kilometers (186,000 miles) per second, takes no less than ten years to reach us from this sun, which, nevertheless, is one of our neighbors.
The Little Dog, in which Procyon (α, of first magnitude) shines out, is above its big brother. With the exception of α, it has no bright stars.
Fig. 13.—Winter Constellations.
Lastly, toward the southern horizon, we must notice the Hydra, Eridanus, the Whale, the Southern Fish, the Ship, and the Centaur. This last constellation, while invisible to our latitudes, contains the star that is nearest to the Earth, α, of first magnitude, the distance of which is 40 trillion kilometers (25 trillion miles).
Fig. 14.—Spring Constellations.
The feet of the Centaur touch the Southern Cross, which is always invisible to us, and a little farther down the Southern Pole reigns over the icy desert of the antarctic regions.