« PreviousContinue »
(If a straight line, connecting Almaack with Merach, be produced southwesterly, 8° farther, it will reach to Delta, a star of the 3d magnitude in the left breast. This star may be otherwise known by its forming a line, N. and S. with two smaller ones on either side of it; or, by its constituting, with two others, a very small triangle, S. of it.
(Nearly in a line with Almaack, Merach and Delta, but curving a little to the N. 7° farther, is a lone star of the 2d magnitude, in the head, called Alpheratz. This is the N. E. corner of the great "Square of Pegasus," to be hereafter described.
It will be well to have the position of Alpheratz well fixed in the mind, because it is but one minute west of the great equinoctial colure, or first meridian of the heavens, and forms nearly a right line with Algenib in the wing of Pegasus, 14° S. of it, and with Beta in Cassiopeia, 30° N. of it. If a line, connecting these three stars, be produced, it will terminate in the pole. These three guides, in connexion with the North Polar Star point out to astronomers the position of that great circle in the heavens from which the right ascension of all the heavenly bodies is measured.
HISTORY-The story of Andromeda, from which this constellation derives its name, is as follows: She was daughter of Cepheus, king of Ethiopia, by Cassiopeia. She was promised in marriage to Phineus, her uncle, when Neptune drowned the kingdom, and sent a sea monster to ravage the country, to appease the resentment which his favourite Nymphs bore against Cassiopeia, because she had boasted herself fairer than Juno and the Nereides. The oracle of Jupiter Ammon was consulted, and nothing could pacify the anger of Neptune unless the beautiful Andromeda should be exposed to the sea monster. She was accordingly chained to a rock for this purpose, near Joppa, (now Jaffa, in Syria,) and at the moment the monster was going to devour her, Perseus, who was then returning through the air from the conquest of the Gorgons, saw her and was captivated by her beauty.
"Chained to a rock she stood; young Perseus stay'd
His rapid flight, to woo the beauteous maid."
He promised to deliver her and destroy the monster if Cepheus would give her to him in marriage. Cepheus consented, and Perseus instantly changed the sea monster into a rock, by showing him Medusa's head, which was still reeking in his hand. The enraged Phineus opposed their nuptials and a violent battle ensued, in which he, also, was turned into a stone by the petrifying influence of the Gorgon's head.
The morals, maxims, and historical events of the ancients, were usually communicated in fable or allegory. The fable of Andromeda and the sea monster, might mean that she was courted by some monster of a sea-captain, who at tempted to carry her away, but was prevented by another more gallant and suc. cessful rival.
THE FISHES. This constellation is now the first in order, of the 12 constellations of the Zodiac, and is usually represented by two fishes tied a considerable distance apart, at the extremities of a long undulating cord, or riband. It occupies
Describe the magnitude and position of Delta. How may this star be otherwise known? Describe the position and magnitude of Alpheratz. What position does this star occupy in the great square of Pegasus? Why is it important to have the position of this star well fixed in the mind? What is the present order of the Fishes among the constellations of the Zodiac? How is it represented? Describe its outline and space in the heavens.
a large triangular space in the heavens, and its outline at first is somewhat difficult to be traced.)
In consequence of the annual precession of the stars, the constellation Pisces has now come to occupy the sign Aries; each constellation having advanced one whole sign in the order of the Zodiac. The sun enters the sign Pisces, while the earth enters that of Virgo, about the 19th of February, but he does not reach the constellation Pisces before the 6th of March. The Fishes, therefore, are now called the "Leaders of the Celestial Hosts."-See Aries.
That loose assemblage of small stars directly south of Merach, in the constellation of Andromeda, constitutes the Northern Fish, whose mean length is about 160, and breadth, 7. Its mean right ascension is 15°, and its declination 250 N. Consequently, it is on the meridian the 24th of November; and, from its breadth, is more than a week in passing over it. The Northern Fish and its riband, beginning at Merach, may, by a train of small stars, be traced, in a S. S. easterly direction, for a distance of 33°, until we come to the star El Rischa, of the 3d magnitude, which is situated in the node, or flexure of the riband. This is the principal star in the constellation, and is situated 20 N. of the equinoctial, and 53 minutes east of the meridian.
Seven degrees S. E. of El Rischa, passing by three or four very small stars we come to Mira, in the Whale, a star of about the 3d magnitude, and known as the Wonderful Star of 1596. El Rischa may be otherwise identified by means of a remarkable cluster of five stars in the form of a pentagon, about 150 E. of 4.Sce Cetus.
From El Rischa the riband or cord makes a sudden flexure, doubling back across the ecliptic, where we meet with three stars of the 4th and 5th magnitude situated in a row 3° and 4 apart, marked on the map Zeta, Epsilon, Delta From Delta the riband runs north and westerly along the Zodiac, and terminates at Beta, a star of the 4th magnitude, 11° S. of Markab in Pegasus.
This part of the riband including the Western Fish at the end of it, has a mean declination of 50 N., and may be seen throughout the month of November, passing the meridian slowly to the W., near where the sun passes it on the 1st of April Twelve degrees W. of this Fish, there are 4 small stars situated in the form of the letter The two Fishes, and the cord between them, make two sides of a large triangle, 30 and 400 in length, the open part of which is towards the N. W When the Northern Fish is on the
What are the size and position of the Northern Fish? When, and how long is it on the beridian? How may it be traced? What is the principal star in this constellation, and where is it situated? How far, and in what direction from Alpha, is Mira, in the Whale? By what peculiar appellation is this star known? What is the direction of the riband from Alpha? What stars do we meet with, where the riband doubles back across the eclipt? What is the direction of this part of the riband from Delta, and where does it terinate? What are its mean declination, and the time of its passing the meridian? What striking cluster is seen about 120 W. of the Western Fis? What geometrical figure Dry be conceived to be formed by the two Fishes and the cord between them? Where is the Western Fish when the Northern is on the meridian?
meridian, the Western is nearly 2 hours past it. stellation is bounded N. by Andromeda, W. by Andromeda and Pegasus, S. by the Cascade, and E. by the Whale, the Ram and the Triangles.
When, to enable the pupil to find any star, its direction from another is given, the latter is always understood to be on the meridian.
After a little experience with the maps, even though unaccompanied by directions, the ingenious youth will be able, of himself, to devise a great many expedients and facilities for tracing the constellations, or selecting out particular
HISTORY.-The ancient Greeks, who have some fable to account for the origin of almost every constellation, say, that as Venus and her son Cupid were one day on the banks of the Euphrates, they were greatly alarmed at the appearance of a terrible giant, named Typhon. Throwing themselves into the river, they were changed into fishes, and by this means escaped danger. To commemorate this event, Minerva placed two fishes among the stars.
According to Ovid, Homer, and Virgil, this Typhon was a famous giant. He had a hundred heads, like those of a serpent or dragon. Flames of devouring fire darted from his mouth and eyes. He was no sooner born, than he made war against heaven, and so frightened the gods, that they fled and assumed different shapes. Jupiter became a ram; Mercury, an ibis; Apollo, a crow; Juno, a cow; Bacchus, a goat; Diana, a cat; Venus, a fish, &c. The father of the gods, at least, put Typhon to flight, and crushed him under Mount Etna.
The obvious sentiment implied in the fable of this hideous monster, is evidently this: that there is in the world a description of men whose mouth is so "full of cursing and bitterness," derision and violence, that modest virtue is sometimes forced to disguise itself, or flee from their presence.
In the Hebrew Zodiac, Pisces is allotted to the escutcheon of Simeon. No sign appears to have been considered of more malignant influence than Pisces. The astrological calendar describes the emblems of this constellation as indicative of violence and death. Both the Syrians and Egyptians abstained from eating fish, out of dread and abhorrence; and when the latter would represent any thing as odious, or express hatred by hieroglyphics, they painted a fish.
In using a circumpolar map, face the pole, and hold it up in your hands in such a manner that the part which contains the name of the given month shall be upperinost, and you will have a portraiture of the heavens as seen at that time. The constellations about the Antarctic Pole are not visible in the United States; those about the Arctic or northern pole, are always visible.
CASSIOPEIA is represented on the celestial map, in regal state seated on a throne or chair, holding in her left hand the branch of a palm tree. Her head and body are seen in the Milky Way. Her foot rests upon the Arctic Circle, upon which her chair is placed. She is surrounded by the chier personages of her royal family. The king, her husband, is on her right hand-Perseus, her son-in-law, on her left-and Andromeda, her daughter, just above her.
This constellation is situated (26° N. of Andromeda, and midway between it and the North Polar Star. It may be
What are the boundars of this constellation? How is the constellation Cassiopeia By whom is she surrounded? How is this constellation SIMA & STUDY Komeda and the polar star?
seen, from our latitude, (at all hours of the night, and may be traced out at almost any season of the year.) Its mean declination is 60° N. and its right ascension 120. It is on our meridian the 22d of November, but does not sensibly change its position for several days for it should be remembered that the apparent motion of the stars becomes slower and slower, as they approximate the poles.)
(Cassiopeia is a beautiful constellation, containing 55 stars that are visible to the naked eye; of which five are of the 3d magnitude, and so situated as to form, with one or two smaller ones, the figure of an inverted chair.)
"Wide her stars
Dispersed, nor shine with mutual aid improved;
(Caph, in the garland of the chair, is almost exactly in the
equinoctial colure, 30° N. of Alpheratz, with which, and the Polar Star, it forms a straight line.) [See note to Andromeda.] Caph is therefore on the meridian the 10th of November, and one hour past it on the 24th. It is the westernmost star of the bright cluster. Shedir*, in the breast, is the uppermost star of the five bright ones, and is 5° S. E. of Caph:) the other three bright ones, forming the chair, are easily distinguished, as they meet the eye at the first glance.
There is an importance attached to the position of Caph that concerns the mariner and the surveyor. It is used, in connexion with observations on the Polar Star, for determining the latitude of places, and for discovering the magnetic variation of the needle.
It is generally supposed that the North Polar Star, so called, is the real immove able pole of the heavens; but this is a mistake. It is so near the true pole that it has obtained the appellation of the North Polar Star; but it is, in reality, more than a degree and a half distant from it, and revolves about the true pole every 24 hours, in a circle whose radius is 1° 35'. It will consequently, in 24 hours, be twice on the meridian, once above, and once below the pole; and twice at its greatest elongation E. and W. [See North Polar Star.]
The Polar Star not being exactly in the N. pole of the heavens, but one degree and 35 minutes on that side of it which is towards Caph, the position of the latter becomes important as it always shows on which side of the true pole the polar star is.)
There is another important fact in relation to the position
Shedir, from El Seder, the Seder tree; a name given to this constellation by Ulugh Beigh.
When may it be seen from this latitude? When is it on our meridian? How is the motion of the stars affected as they approach the poles? How many principal stars in this constellation, and what is their appearance? Describe the situation of Caph. When is Caph on the meridian? What is the relative position of Shedir? Why is the position of Caph important?
of this star. It is equidistant from the pole, and exactly opposite another remarkable star in the square of the Great Bear, on the other side of the pole. [See Megrez.] It also serves to mark a spot in the starry heavens, rendered memorable as being the place of a lost star. Two hundred and fifty years ago, a bright star shone 5° N. N. E. of Caph, where now is a dark void!
On the 8th of November, 1572, Tycho Brahe and Cornelius Gemma saw a star in the constellation of Cassiopeia, which became, all at once, so brilliant, that it surpassed the splendour of the brightest planets, and might be seen even at noonday! Gradually, this great brilliancy diminished, until the 15th of March, 1573, when, without moving from its place, it became utterly extinct.)
Its colour, during this time, exhibited all the phenomena of a prodigious flame-first it was of a dazzling white, then of a reddish yellow, and lastly of an ashy paleness, in which its light expired. It is impossible, says Mrs. Somerville, to imagine any thing more tremendous than a conflagration that could be visible at such a distance.) It was seen for sixteen months.
Some astronomers imagined that it would reappear again after 150 years; but it has never been discovered since.) This phenomenon (alarmed all the astronomers of the age, who beheld it; and many of them wrote dissertations concerning it.
Rev. Professor Vince, one of the most learned and pious astronomers of the age, has this remark:-The disappearance of some stars may be the destruction of that system at the time appointed by the DEITY for the probation of its inhabitants; and the appearance of new stars may be the for mation of new systems for new races of beings then called into existence to adore the works of their Creator."
Thus, we may conceive the Deity to have been employed from all eternity, and thus he may continue to be employed for endless ages; forining new systems of beings to adore him; and transplanting beings already formed into hap pier regions, who will continue to rise higher and higher in their enjoyments, and go on to contemplate system after system through the boundless universe. LA PLACE says:-"As to those stars which suddenly shine forth with a very vivid light, and then immediately disappear, it is extreinely probable that great conflagrations, produced by extraordinary causes, take place on their surface.. This conjecture, continues he, is confirmed by their change of colour, which is analogous to that presented to us on the earth by those bodies which are set on fire and then gradually extinguished."
The late eminent Dr. Good also observes that-Worlds and systems of worlds
What memorable spot does Caph serve to mark out? Describe the phenomenon of the lost star. What does Mrs. Somerville say of it? How long was it seen? Has any thing been discovered of it since? How did this phenomenon affect the astronomers of the age? What does Vince say of the disappearance of some stars, and the new appearance of others? Repeat the observations of Dr. Good upon the subject of new stars appearing and disappearing.