Of the effect of the Precession of the Equinoxes, to which Emerson refers, we have already spoken. But it is a long time in the future that Vega will begin, or rather resume, its reign as the Star of the North. And, curiously enough, when that time comes the northern hemisphere will have its Summer Solstice when the sun is just opposite to the place which it now occupies at that season, and when Antares will be no more a summer star, but will flash its ruddy light upon the snows of a winter longer and colder than the winters that we know, while Orion will blaze above the summer landscapes. This immense revolution, some have thought, may be the measure of the “Great Year” of Plato, and if the chronology adopted for dating the early remains of civilization recently uncovered in Crete is correct, we have evidence that mankind has persisted through one of these vast periods, and that nations flourished round the Mediterranean when Vega was formerly the Pole-star.
The beauty of Vega, which has been admired and commented on from the earliest times, is much enhanced when it is viewed with a telescope. Then the blueness of its light becomes evident, and one is the more astonished at the unquestionable fact that it outshines the sun a hundred times. A sapphire sun, a hundred times more brilliant than ours! The proper motion of the solar system, which carries us through space about twelve miles per second, is bearing us almost directly toward Vega, so that as future ages unroll the star should become brighter and brighter with decrease of distance, until eventually it may outshine every other orb in the firmament, and put Sirius himself to shame by its overpowering splendor.
The little star Epsilon (ε), the northernmost one of the pair near Vega, is a celebrated quadruple, easily seen as such with a telescope of moderate power.
A little less than half way from Beta (β) to Gamma (γ) the telescope discovers the wonderful “Ring Nebula,” a delicate circle of nebulous light with a star in the centre. This star is more conspicuous in photographs than in telescopic views. This object has been regarded as a visual proof of the correctness of Laplace’s theory of the origin of the solar system from nebulous rings surrounding a central sun, but the Lick photographs show that the ring in this case is of a strangely complex constitution. Beta is both a binary and a variable star.
Buried in the Milky Way, east of Lyra, lies the great “Northern Cross” in the constellation Cygnus. It is more perfect than the famous “Southern Cross,” and much larger. The star Alpha (α), at the head of the main beam of the cross, is also called Denib, the “Tail,” as it is situated in the tail of the “Swan,” Cygnus. Its parallax is undetermined, and Newcomb placed it in his “XM” class, described under Spica in Chapter I. The Milky Way is exceedingly beautiful in Cygnus. Note particularly the broad gaps and rifts in it. Around and above the head of the cross there are dark spaces, which are specially impressive when the eyes are partly averted from them. Downward from Cygnus the stream of the galaxy is seen to be partially split longitudinally. It resembles a broad river meandering, in the droughts of the “dog days,” over flats and shallows, and interrupted with long sand-bars. How can stars have been thrown together into such forms? What whirls and eddies of the ether can have made these pools of shining suns?
The star in the foot of the cross, Beta (β), or Albireo—a beautiful name without signification, since Allen shows that it originated in a blunder (see his Star Names and Their Meanings)—is one of the most attractive objects in the heavens for those who are fortunate enough to possess a telescope. The smallest glass easily shows it to be double, and the combination is unrivalled for beauty, the larger star being a pale topaz and the smaller a deep sapphire. Their magnitudes are three and seven, and their distance apart about 34″. I have separated them with a field-glass.
Cygnus contains one of the nearest stars in the sky, a twinkler not too easily seen with the naked eye—a striking proof of the fact that the mere faintness of a star is in itself no indication of excessive distance. This is known as 61 Cygni, and will be found on [Chart X]. It is a double, possible binary, easily separated with a small telescope, the distance being about 21″. The distance of 61 Cygni is about 40,000,000,000,000 miles. It was long known as the second nearest star in the sky, the nearest being Alpha Centauri in the southern hemisphere; but at least one nearer one has more lately been discovered, and it, too, is a very small star. The combined luminosity of the two stars in 61 Cygni is only one-tenth that of the sun. Amid so many giants it is reassuring to find a sun smaller than ours; it restores our self-esteem to find that our solar hamlet is not the very least in the empire of space.
Southeast of Cygnus, near the eastern shore of the starry river, is Aquila, the “Eagle.” Its chief star, Altair, “Eagle,” recalls Antares, not by its color, for it is not red but white, but by the singular arrangement of two small stars standing one on either side of it. Here, too, the Milky Way is very splendid, attaining astonishing brightness lower down, in Scutum Sobieskii, “Sobieski’s Shield.” The naming of this constellation was a posthumous reward to the heroic king, John Sobieski, for saving Europe by the defeat of the Turks under the walls of Vienna, after their victorious advance from Constantinople, emphasized in the public mind by the appearance of Halley’s Comet, had seemed to threaten a Moslem conquest. Twice Halley’s Comet had alarmed Europe in connection with the Turks, first in 1456, after they had taken Constantinople, and again in 1682 when they swept upon Vienna, so that it was a natural thought to associate Sobieski’s victory with some “sign in the sky,” and a more appropriate one could hardly have been found than the “shield,” bossed with star-clusters, which Hevelius selected for the purpose. The southern part of the constellation Aquila is sometimes called Antinous. For the beautiful Oriental legend of the Spinning Damsel and the Magpie Bridge connected with Aquila and Lyra, see Astronomy with the Naked Eye. Newcomb gives Altair ten times the luminosity of the sun.
The constellations Delphinus and Anser et Vulpecula will be dealt with in the next chapter. In the mean time let us turn to the western half of the sky.
Just west of the meridian, near the zenith, gleams the glorious Northern Crown, Corona Borealis. The head of Serpens is right underneath it. It is, perhaps, the most charming of all asterisms. It could hardly be called anything else than a crown or a wreath. The perfection of the figure is surprising. If its stars were larger it would be the cynosure of the sky, but small as they are they produce an effect of ensemble that could not have been exceeded if human hands had arranged them there. The superior brightness of one of them, Alpha “Gemma,” or “The Pearl,” adds greatly to the effectiveness of the combination. It is the work of a master jeweller! Yet, as I have elsewhere shown, this curious assemblage of stars is but a passing phenomenon, for they are travelling in various directions, with various speeds, and in the course of time the Northern Crown will dissolve like a figure in the clouds. In Greek mythology it was generally called the Crown of Ariadne. Just under the star Epsilon (ε) is a wonderful variable, which in 1866 suddenly blazed up to the second magnitude, and was for a time regarded as a new star. Nothing is known of its periods of change. It is not now visible to the naked eye.