Page:Popular Science Monthly Volume 46.djvu/310

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296
THE POPULAR SCIENCE MONTHLY.

present too close for ordinary telescopes, although it was once within their reach; Σ 729, double, magnitudes six and eight, distance 2″, p. 26°, the smaller star pale blue. Try it with a four inch, but five-inch is better; Σ 816, double, magnitudes six and half and eight and a half, distance 4″, p, 289°; ψ 2, double, magnitudes five and a half and eleven, distance 3″, or a little less, p. 322°; 905, star cluster, contains about twenty stars from eighth to eleventh magnitude; 1267, nebula, faint, containing a triple star of eighth magnitude, two of whose components are 51" apart, while the third is only 1·7″ from its companion, p. 85°; 1376, star cluster, small and crowded; 1361, star cluster, triangular shape, containing thirty stars, seventh to tenth magnitudes, one of which is a double, distance 2·4″.

Let us now leave the inviting star-fields of Orion and take a glance at the little constellation of Lepus, crouching at the feet of the mythical giant. We may begin with a new kind of object, the celebrated red variable R Leporis (map No. 1). This star varies from the sixth or seventh magnitude to magnitude eight and a half in a period of four hundred and twenty-four days. Hind's picturesque description of its color has frequently been quoted. He said it is "of the most intense crimson, resembling a blood-drop on the black ground of the sky." It is important to remember that this star is reddest when faintest, so that if we chance to see it near its maximum of brightness it will not impress us as being crimson at all, but rather a dull, coppery red. Its spectrum indicates that it is smothered with absorbing vapors, a sun near extinction which, at intervals, experiences an accession of energy and bursts through its stifling envelope with explosive radiance, only to faint and sink once more. It is well to use our largest aperture in examining this star.

We may also employ the five-inch for an inspection of the double star ι, whose chief component of the fifth magnitude is beautifully tinged with green. The smaller companion is very faint, eleventh magnitude, and the distance is about 13″, p. 337°.

Another fine double in Lepus is κ, to be found just below ι; the components are of fifth and eighth magnitudes, pale yellow and blue respectively, distance 2⋅5″, p. 360°; the third-magnitude star a has a tenth-magnitude companion at a distance of 35″, p. 156°, and its neighbor β (map No. 2), according to Burnham, is attended by three eleventh-magnitude stars, two of which are at distances of 206″, p. 75°, and 240″, p. 58°, respectively, while the third is less than 3″ from β, p. 288°; the star γ (map No. 2) is a wide double, the distance being 94″, and the magnitudes fourth and eighth. The star numbered 45 is a remarkable multiple, but the components are too faint to possess much interest for those who are not armed with very powerful telescopes.