Antares is _the_ summer star, and with it and the Scorpion we will begin. Not so bright as Arcturus or Vega, which are now high aloft, it has a charm peculiar to itself, arising partly from its fervid color, partly from its surroundings, and partly from its position, not too high above the southern horizon, which renders observation of the star comparatively easy. The color is so distinctive that one might think that he could recognize Antares chromatically if it were suddenly transported to some other region of the sky and placed amid a strange environment. Sometimes a flash of its fiery rays, striking sidewise into the eye as one is looking elsewhere, startles the observer like a red meteor. It is well named Antares--“Anti-Mars.” With the telescope the wonder of color is increased, for close by the great star the glass reveals a smaller one of a _vivid green_, an all but incredible combination of complementarily tinted suns. And these suns are undoubtedly actually linked together into a system, so that, if there are planets revolving around both or either, the inhabitants of those planets may behold the spectacle of two suns, one crimson and the other emerald! The large star is of the first magnitude, and the small one of the seventh; angular distance 3″.7. The companion of Antares is historically associated with the most interesting of American astronomers, a man whose life was a romance, Gen. O. M. Mitchel. When his long-cherished design of setting up a great telescope in America was at last fulfilled, at Cincinnati, in 1845, one of his first achievements was the discovery, to the surprise of the astronomers of Europe, of the green star hiding in the rays of Antares. At times it has been seen emerging from behind the moon, after an occultation, ahead of its red comrade. With a parallax of 0″.02, Newcomb estimated the luminosity of Antares at nine hundred times that of our sun, and yet the spectroscope indicates that it is a dying sun, fast approaching extinction. In its younger days it may have been an orb of prodigious splendor.