Flows trembling, wave on wave, from sun to sun,
And whitens the long path to heaven’s extreme:
Distinguished tract!“
From an attentive examination of the stars with good telescopes, many that appear only single to the naked eye, are found to consist of two, three, or more stars. The late Dr. Maskelyne observed the α Herculis to be a double star, and other astronomers have discovered many more to be double. Dr. Herschell has found 700; of these about forty had been observed before. The following will serve as a specimen, and afford the observer a few objects for his attention. α Herculis is a beautiful double star: the two bodies are apparently unequal: the largest is red, and the smallest of a blueish color inclining to green. γ Andromedæ, double, very unequal: the larger of a reddish white color; the smaller a fine bright sky blue, inclining to green. β Lyræ, quadruple, unequal white, but three out of the four inclined to red. ε Bootis, double, very unequal, larger, of a reddish color; the smaller is blue, or of a faint lilac color. α Lyræ, double, very unequal; the larger is a fine brilliant white, the smaller dusky.
New stars sometimes appear, while others disappear. Several stars mentioned by ancient astronomers are not now to be found: several are now visible to the naked eye, which are not mentioned in ancient catalogues; and some stars have suddenly appeared, and again after a considerable interval vanished. Fortunio Liceti, a celebrated physician, who died in 1656, in Padua, published a treatise, entitled, “De novis Astris et Cometis.” In it he gives us an ample account of the several new stars spoken of by the ancients, among which he mentions that remarkable one which appeared A.D. 389, near the Eagle. It was as bright as the planet Venus, for the space of three weeks, but afterwards entirely disappeared. In the ninth century, the Arabian astronomers, Massahala, Haly, and Albumazar, observed a new star in the 15th degree of Scorpio, whose light equalled that of the moon in her first octant: it was visible for four months. Cyprianus Leovitius relates, that in the reign of the emperor Otho, A.D. 946, a new star was seen between the constellations of Cepheus and Cassiopeia; and also that another was seen A.D. 1264, very near the same part of the heavens, which had no proper motion. One of the most celebrated of the new stars is that discovered by Cornelius Jansen, November 8, 1572, in the chair of Cassiopeia: it exceeded Sirius in brilliancy, and Jupiter in apparent magnitude; it gradually decayed; and, after sixteen months, disappeared. On the 13th of August, 1596, David Fabricius observed a new star in the neck of the Whale, and it disappeared after October in the same year, but was supposed to be again discovered in the year 1637. In the year 1600, William Jansen discovered a changeable star in the neck of the Swan. It was seen by Kepler, who wrote a treatise upon it, and determined its place to be 16° 18ʹ ♒, and 55° 30ʹ or 32ʹ north latitude. Ricciolus saw it in 1616, 1621, and 1624. Cassini saw it again in 1655; it increased till 1660; then decreased, and at the end of 1661 it disappeared. In November, 1665, it appeared again, and disappeared in 1681. In 1715 it appeared, as it does at present, and is of the sixth magnitude. In 1686, Kircher observed χ in the Swan, to be a changeable star in the neck of that constellation; and, from twenty years’ observations, the period of the return of the same phases was found to be 405 days. In 1604, Kepler discovered a new star near the heel of Serpentarius, so very brilliant that it exceeded every fixed star, and even Jupiter, in apparent magnitude. For more recent discoveries, see Dr. Herschell’s paper, “On the proper Motion of the Sun and the Solar System, with an account of the several changes that have happened among the fixed stars since the time of Mr. Flamsteed,” vol. lxxiii, of the Philosophical Transactions, or the fifteenth of the Abridgment.
All the stars seem to have a common and general motion about the pole of the ecliptic, at the rate of a degree in seventy-two years; this is occasioned by the precession of the equinoctial points. In consequence of this apparent motion, the constellations change their positions in regard to the equinoctial points. Hence it is, that the constellation Aries now is in the sign Taurus, and Taurus occupies the sign Gemini. It has been the common opinion that the fixed stars have no real motion, but the accurate observations of modern astronomers show, that some of them have a motion peculiar to themselves, by which they slowly change their places. Thus Arcturus is found to approach the ecliptic about four minutes in 100 years; and its distance from a small star near it has been sensibly changed during the last century. Sirius seems to recede from the ecliptic about two minutes per century. Similar motions have been observed in Aldebaran, Rigel, the eastern shoulder of Orion, the Goat, the Eagle, &c. Other stars have been observed to have a motion in different directions. Perhaps all the stars have similar motions, which are performed by certain fixed laws in spaces, which, though very large in reality, yet, because of their immense distance, subtend at the earth angles so very small, as in some cases to be quite imperceptible, while in other cases they may be observed, as in the stars above-mentioned; and on this rational supposition the appearance and disappearance, and variations in magnitude, of some stars may be accounted for.
The fixed stars do not appear to be all regularly disseminated through the heavens, but the greater part of them are collected into clusters; and it requires a large magnifying power, with a great quantity of light, to distinguish separately the stars which compose these clusters. With a small magnifying power, and small quantity of light, they only appear as minute whitish spots, much like small light clouds, and thence they are called nebulæ. The number of nebulæ was formerly imagined to be about 103; but Dr. Herschell, early in the year 1784, had discovered 469 more, and since then has given a catalogue of 2,000 nebulæ which he has discovered. The most careful and accurate observations give great reason to conclude, that they all consist of large masses or clusters of stars at prodigious distances from our system. Dr. Herschell is of opinion the starry heaven is replete with these nebulæ, and that each of them is a distinct and separate system independent of the rest. The milky way he supposes to be that particular nebulæ in which our sun is placed; and, in order to account for the appearance it exhibits, he supposes its figure to be much more extended towards the apparent zone of illumination, than in any other direction; which is a supposition that he thinks allowable, from the observations he has made on the figures of other nebulæ.
That there are other worlds, beside our earth, inhabited by rational beings, endued with bodily constitutions adapted to the nature and economy of the respective planets for which they are destined, is a conjecture that approaches the nearest to certainty. There is scarcely any doubt now remaining amongst philosophers, that our moon is a habitable globe. The most accurate observations that have been made with the most powerful telescopes, have confirmed the opinion. The surface of the moon seems to be diversified by high mountains, large valleys, and small and larger collections of water; consequently she resembles our earth; and there can be no doubt that our earth serves as a moon to the moon, whose inhabitants, comparing it with the sun, may well say,
——“gives us his blaze again
Void of its flame, and sheds a softer day;“