Page:Popular Science Monthly Volume 46.djvu/492

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THE POPULAR SCIENCE MONTHLY.

ponents not exceeding 0·8″, position angle 64°. Σ 958 is a pretty double, both stars being of the sixth magnitude, distance 5″, p. 257°. Still finer is Σ 1009, a double, whose stars are both a little above the seventh magnitude and nearly equal, distance 3″, p. 156°. A low power suffices to show the three stars in 19, their magnitudes being six and a half, seven and a half, and eight, distances 15″, p. 312°, and 215″, p. 358°. Webb describes the two smaller stars as plum-colored. Plum-colored suns?

At the opposite end of the constellation are two fine doubles, Σ 1333, magnitudes six and a half and seven, distance 1·4″, p. 39°; and 38, magnitudes four and seven, distance 2·9″, p. 235°.

Under the guidance of map No. 6 we turn to Leo, which contains one of the leading gems among the double stars, γ, whose components, of third and fourth magnitudes, are respectively yellow and green, the green star, according to some observers, having a peculiar tinge of red. Their distance apart is 3·5″, p. 114°, and they are undoubtedly in revolution about a common center, the probable period being about four hundred years. The three-inch glass should separate them easily when the air is steady, and a pleasing sight they are.

The star ι is a closer double, and also very pretty, magnitudes four and eight, colors lemon and light blue, distance 2·7″, p. 65°. Other doubles are τ, magnitudes five and seven, distance 95″, p 170°; 88, magnitudes seven and nine, distance 15″, p. 320°; 90 triple, magnitudes six, seven and a half, and ten, distance 3·5″, p 209°, and 59″, p. 234º; 54, magnitudes four and a half and seven distance 6·2″, p. 102°; and 49, magnitudes six and nine, distance 2·4″, p. 158°.

Leo contains a remarkable variable star, R, deep red in color, and varying in a space of a hundred and forty-four days from the fifth to the tenth magnitude. It has also several nebulæ, of which only one needs special mention, No. 1861. This is spindle-shaped, and large telescopes show that it consists of three nebulae. The observer with ordinary instruments finds little to see and little to interest him in these small, faint nebulæ.

We may just glance at two double stars in the small constellation of Sextans, situated under Leo. These are: 9, magnitudes seven and eight, distance 53″, p. 292°; and 35, magnitudes six and seven, distance 6·9″, p. 240°.

Coma Berenices (map No. 6) contains several interesting objects. Let us begin with the star 2, a double, of magnitudes six and seven and a half, distance 3·6″, p. 240°. The color of the smaller star is lilac. This hue, although not extremely uncommon among double stars elsewhere, recurs again and again, with singular persistence, in this little constellation. For instance, in the very next star that we look at, 12, we find a double whose