The Music of the Spheres/Chapter 4

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4384372The Music of the Spheres — Chapter IV.Florence Armstrong Grondal


THE TWO DIPPERS AND DRACO, THE DRAGON
These stars circle about Polaris, the North Star, and are visible at any hour during the night throughout the year.

CHAPTER IV

THE TWO SKY DIPPERS AND DRACO, THE DRAGON

The Big Dipper

A Broken handled duplicate of the old fashioned tin dipper that used to hang by the well, lies twinkling in the northern half of the sky. This Dipper is ornamented with seven bright stars although a telescope or a field-glass will disclose dozens more encrusted on its handle and a starry phosphorescence in its bowl.

This Dipper may be found near the zenith, almost overhead, during the early evening hours in April and May; it is west of the North Star in July and August, near the northern horizon in October and November and in the east during January and February.

Although every twenty-four hours this Sky Dipper swings completely around the North Star, half of the journey is invisible because the strong light of the sun prevents us from seeing the stars in the daytime.

"The fiery sun, when wheeling up heaven's height,
Obscures the stars and the moon's holy light."
Leonidas.

The stars, however, rise two hours earlier every month and this brings the Dipper, when observed during the early hours of darkness, to different positions in the sky during the different seasons.

Since this conspicuous star figure travels completely around the arctic circle of the heavens in twenty-four hours, the space within this circle has been likened to a great star clock, the two outer stars on the bowl—called "The Pointers"—forming the hour hand which always points toward the center of the clock marked by the North Star. With a little attention anyone may learn to judge the time by this timepiece and wager as much on it as the Carrier in Shakespeare's King Henry IV who looks up as he enters the Inn Yard with his lantern and remarks:

"Heigh-ho! An't be not four by the day, I'll be hanged, Charles' Wain is over the new chimney, and yet our horse is not packed."

The Big Dipper is called "Charles' Wain" in England, the bowl being the wagon or wain, and the stars on the handle, the horses. It is also called "David's chariot" and the "Plowshare." In Rome these seven bright stars were called "Septentriones" or "The Seven Plowing Oxen"; in Greece, simply the "Triones."

"'Twas the time when all things are silent, and Boötes had turned his wain with the pole obliquely directed among the Triones."

Ovid's Metamorphoses.

Boötes, so the story runs, being of an ingenious turn of mind, tilled his land in fine order by inventing the plow which he hitched to two oxen. For this he was given the title of the "Herdsman" or the "Ox-driver" and placed in the heavens to follow the stars of the Big Dipper which resembles a "wain" or a plow. Boötes' constellation, though very large, is formed of faint stars,—with the exception of one brilliant golden-yellow star which may be located by drawing a curve from the end of the Big Dipper's handle.

The little star just above the star in the crook of the handle of the Dipper is sometimes spoken of as a 'rider.' The Arabs call these two stars a "Horse and its Rider," the English call the rider "Jack-on-the-Middle-Horse," while the Germans call him "Hans-on-the-Middle Horse." Hans chose this position in preference to any other on the face of the earth or in the kingdom of Heaven.

Astronomers have still another name for the Horse and its Rider. To them it is a "naked-eye double," the tiny star being called "Alcor," and the one on the Dipper's handle just below it, "Mizar." A 3-inch telescope discloses a still closer companion to Mizar which has a decided greenish tinge in its light. Of the two stars composing Mizar, each one is itself composed of two, which revolve around a common center of gravity in a period to be counted in thousands of years. This wonderful law of gravitation which holds not only planets in their orbits, but also stars, was discovered by Sir Isaac Newton, an English philosopher and mathematician. Two stars revolving around a common center of gravity in this manner are called a "binary"; in the case of Mizar and its companion, each of the two visual components is called a "spectroscopic binary." The brighter component was discovered to be a binary in 1889 by E. C. Pickering with the aid of a spectroscope and the fainter component was found to be a spectroscopic binary in 1908 by Frost and Lee. Alcor is also a spectroscopic binary.

The stars are such an exceedingly great distance from the earth that even though they are in constant motion, they do not seem to change their relations to other stars through long periods of time. The whole configuration of the Big Dipper will some day be changed because its stars are traveling in various directions. Through the skill of various scientists this infinitesimal difference in motion is detected and recorded,—not only that a star is moving, but which way and how fast! Thus the spectroscope exploded the old idea that the stars were "fixed." The facts, however, are amazing and one must immediately readjust his ideas of what constitutes big and little, fast and slow, for in studying astronomy the small distances on our earth and the vast distances in space, and man-made speed and God-made speed, can hardly even be compared.

The stars of the Big Dipper are an exceptional group for they are all bright stars of the second magnitude, with the exception of Megrez at the junction of the handle to the bowl. These seven stars, and the "Rider," were given names by the Arabian astronomers, and although modern astronomers prefer for the most part a Greek letter prefixed to the genitive case of the Latin name of the constellation—such as β Ursae Majoris—these names are rather interesting to know. Starting from the top of the Big Dipper's handle, the Arabian names are as follows: Benetnasch, Mizar, Alioth, Megrez, Phaed, Merak, and Dubhe.

The Little Dipper

The "Little Dipper" hangs on the Pole of the Heavens, swinging swiftly around night after night, century after century. It hangs stiffly, as a dipper should, from the bright golden nail of the North Star. From its appearance, it would seem that the rapid motion near the pivot of the starry dome had caused its handle to bend forward at a most precarious angle—surely nothing less than the immortality conferred upon it as a part of Ursa Minor could prevent it from flinging its bowl through the depths of space and whirling henceforth an uninteresting stub of a handle.

The Little Dipper is rather faintly outlined, the only bright stars being those which mark the extremities. The two more conspicuous stars were named "The Guards" for it was thought that they protected the "hole in which the axle of the earth is borne." This "hole," which was imagined as keeping in place the north pole of the heavens, is marked by the North Star. To be exact, the North Star does not mark its precise location but is about twice the diameter of the moon away from it. Such a small distance, however, is scarcely discernible to the eye.

As mentioned before, all the stars travel in unchanged order along their arcs from east to west except this one star which marks the north pole of the heavens. There is no star directly above the pole of the southern hemisphere of our earth. The North Star, or "Polaris," is therefore the only star which remains in an apparently fixed position in the sky, and all the other stars visible to us whirl around it as a center, although in most cases only a portion of their arcs may be seen. If the earth should falter or halt in its rotation, so would the whirl of the stars, and this remarkable exhibition, which is only a delusion dependent on the motion of the earth, would immediately cease to be.

Polaris has a minute blue companion star which may be viewed in a 2- or 3-inch telescope.

The most reliable method of establishing a true meridian in surveying is to take observations on Polaris. "Amid the blue ice and rose-petal night of the pole" this star is, of course, in the very dome of the sky, and Admiral Peary once had the unique distinction of having it shine directly over his head. But in any other location, this star burns like the light of a signal fire marking the north, and its steady, never-failing presence has always heartened and given a feeling of security to travelers, as well as being useful to surveyors.

The Two Bears and Their Stories

The two sky Dippers are only the flanks and the tails of the whole constellations which are called the "Great Bear" and the "Little Bear." Their names are usually written in Latin—"Ursa Major" and "Ursa Minor."

The tail of the Great Bear, outlined by the bright stars of the Big Dipper's handle, is the most clearly marked portion of his anatomy. So inordinately proud is he of this huge appendage, (which is also, the most clearly marked figure in the sky), that, so old legends assert, he gazes jealously at the lone bright star on the end of the Little Bear's tail in hopes that some day he may gain possession of it and add it to his own. This is another reason why the "Guards" have been placed to watch the North Star.

The feet of this Bear extend to three pairs of stars set nearly equidistant, although there are no stars for one of his forefeet. The Arabs call these the "Doe's Leaps." The Bear's head is sprinkled with a scattered group of faint stars on a line with the bowl of the Dipper.

This interesting creature is most impressive when in the springtime his shadowy, star-decked form crosses the sky near the zenith. He seems closest then and we cramp back our necks to get a better view of this ancient Bear about whom is twined so many legends.


"The Bear that prowled all night about the fold
Of the North Star."
Lowell.

Later, during the autumn months, he walks along the rim of the horizon in the north, but there too often, sad to relate, he is more than half obscured by the mists and fogs which hover about near the surface of the earth.

Many attempts have been made to account for the ridiculous length of the brightly-jeweled tails of the star-bears. Richard A. Proctor in "Easy Star Lessons" suggests that as the star maps were arranged by astronomers who being aware of the many legends but who had themselves never seen a bear, naturally supposed the three bright stars in the handle of the Big Dipper to be Ursa Major's tail and so drew it. Since the Big Dipper was made part of Ursa Major or the Great Bear, the Little Dipper, whose seven principal stars resemble those of Ursa Major, was made part of Ursa Minor, the Little Bear.

Howe remarks in his "Descriptive Astronomy" that the "length of the little fellow's tail might be ascribed to environment." 'Tis reasonable indeed. With the tip of it fastened to the North Star for a pivot it might stretch after being swung round for a few centuries. Perhaps, to go still further, this is the reason it is now so thin and therefore faint, and also why it is broken. The quaint theory of Dr. Thomas Hood, who wrote early in the 17th century, is also quoted as a possible reason for the length of the Great Bear's tail:

"Imagine that Jupiter, fearing to come nigh unto her teeth layde hold on her tayle, and thereby drew her up into heaven, so shee of herself, being very weightie, and the distance from the earth to the heavens very great, there was great likelihood that her tayle must stretch.
"Other reason know I none."

Ursa Major was not a real bear, however, but a beautiful and most unfortunate Arcadian nymph, named Callisto, who had been transformed by Juno, Queen of the Immortals, into this great shaggy creature. Years afterward, Callisto's son Arcas, then a boy half-grown, met the bear on a lonely pathway on the mountains and shot an arrow at the creature. Happily, as was often the way with the gods, Jupiter looked down just then, stopped the arrow in its flight and changed the young boy also into a bear. The bears were then raised to the sky and placed among the stars, for Jupiter straightway:

"Snatched them through the air
In whirlwinds up to heaven and fixed them there."
Ovid's Metamorphoses. (Addison's Trans.)

The place is even yet easily located on account of the clearly marked outlines of the Dippers.

This sympathy on the part of Jupiter aroused Juno to such a jealous rage that she immediately sought a way to bring discomfort to the Bears, particularly to the Bear which was Callisto. It seems that the Greeks believed that the stars enjoyed a dip in the western waves of the ocean before disappearing to the darkness below the horizon, and seeing in this a chance for revenge, Juno harnessed up her peacocks and drove to the palace of Oceanus, the ancient God of the Ocean Stream. Here the goddess found the Ocean God (who was one of the Titans and ruled before Neptune's time), and calling him up from the briny depths inveigled that deity to swear by the river Styx that he would drive the "seven Triones" away from his "azure waters" every time these stars appeared and never, under any circumstances, would he share his hospitality with the Bears. After the long journey from the east across the dimly lighted heavens, this was a hardship difficult to endure, yet to this day, since a god's decree may never be changed, the two Bears turn as they approach the ocean and dare not even linger to sniff the spray. While all the other constellations immerse their stars beneath the waves, these poor creatures again ascend the steep slope of the sky and repeat the big circle about the pole of the heavens with never a rest—nor a bath.

But travelers have quietly observed these stars in a latitude south of 40 degrees, and have noticed, as they approached the equator, that the Bears slip their feet into the sea and still farther south

"despite of Juno, lave
Their tardy bodies in the boreal wave."

Allen, in "Star Names and Their Meanings," comments on the singularity that peoples separated by an impassable ocean had like ideas concerning the resemblance of Ursa Major to a bear.

"Whence came the same idea into the minds of our North American Indians? Was it by accident? The conformation in no way resembles the animal,—indeed the contrary; yet they called them Okuari and Paukunawa, words for bear, long before they were visited by white men. In justice, however, to their familiarity with a bear's anatomy, it should be said that the impossible tail of our Ursa was to them either Three Hunters or a Hunter and two dogs in pursuit of the creature, the star Alcor being the pot in which to cook her. They thus avoided the incongruousness of the present astronomical ideas of Bruin's makeup, although their cooking utensil was inadequate."

According to this legend, which is related from a monograph on "The Celestial Bear" by Stansbury Hagar, the whole bear is represented by the stars of the Big Dipper. The first hunter, who is the first star in the handle of the Dipper, was called the robin and carried the bow with which to kill the bear. The chicadee, the second star in the handle of the Dipper, carried the pot, the little star Alcor, in which to cook the bear. The third hunter, the moosebird, carried the sticks with which to build the fire. Four other hunters followed besides the three represented by the stars in the Dipper's handle.

The chase continues throughout the summer until part of the hunters disappear below the horizon. About mid-autumn the Bear rises up to defend herself but is pierced by an arrow of the robin, and the autumn leaves are stained scarlet from his wounds. The spirit of the dead Bear enters into another Bear and the chase begins again and so keeps up eternally. In the Indian version the group of stars above the hunters (which is the Bear's head in the Ursa Major of the Greeks), is the Bear's den. This den is picturesquely situated on the northern horizon early in the spring and, to the mind of the Indian, the great Bear seems as if it were just emerging after a long winter's hibernation.

There is also an old Iroquois Indian tale which claims that at one time in the distant past the bear had a fine bushy tail but that this tail was frozen off one cold winter when the foolish animal endeavored to catch a fish by letting the long appendage hang through a hole in the ice. In those days, perhaps, the bears were vain creatures,—which might explain, in part, why the star-jeweled tails on the shadowy forms of Ursa Major and Ursa Minor are held with the upright pride of a cat with nine kittens as these mammoth plantigrades nightly promenade on their circular path around the Pole.

Draco, the Dragon

A sinuous line of stars divides the figures of the Great and Little Bears. These stars lie on the huge body of Draco, the Sky Dragon, whose length coils halfway around the axis of the world.

Draco is sometimes called the "Guardian of the Stars," the stars being the golden apples which hang from the pole-tree in the Garden of Darkness. This is rather a pretty conceit as the Dragon's Eyes, represented by the stars Alwaid and Etanin, never rest, that is, never set below the northern horizon of Greece.

The above title was probably suggested by the legend which tells of Laden, the sleepless dragon, that guarded the tree of golden fruit in the Garden of the Hesperides. This garden lay near the feet of Atlas, the giant Titan, who sat on a mountain in northern Africa supporting the dome of the heavens. The bright eyes of this snake were at that time aided in their wakefulness by the silvery, lilting voices of the Hesperides, daughters of Hesperus, whose name was given to the beautiful Evening Star so often seen in this direction. According to one legend, Hercules slew this dragon in order to pick the gleaming fruit and bring it to his cousin Eurystheus as his eleventh Labor, but that this Dragon could be identical with the sky dragon, Draco, whose head lies just beyond the heel of Hercules, is somewhat discounted by other legends which claim that Hercules temporarily supported the weight of heaven while Atlas went down to the garden and got the apples from his nieces. In return for this favor, Atlas gained a little rest.

It has also been suggested that perhaps Draco was the monster "with a body more huge than any mountain pine" and "a roar like a fire among the woodlands," which was entwined around a beech tree in the Grove of Mars, the War-god, at the eastern end of the Euxine (which we now call the Black Sea). On this beech tree was nailed the golden fleece of the wondrous ram which flew into the sky and aided two persecuted children to escape. To obtain this fleece, Orpheus drugged the snake with music while Jason stepped across the mighty coils and tore the golden wool from the tree. After the Argonautic expedition, both the ram and the dragon were placed among the stars.

Still another legend relates that when the gods and the earth-born giants waged their mighty war to gain possession of Olympus, a huge crawling monster had the audacity to anger the Goddess Minerva who seized it and hurled it far into the heavens where it caught on the axis of the world, and froze into immobility before it had time to unwind its contortions. The only time on record that this dragon ever revived from its stupid torpor was when Phæthon, son of Apollo, lost control of the steeds of his sun-chariot and the heated vehicle swerved northward from the beaten path.


"Then the folded Serpent next the frozen pole,
Stiff and benumb'd before, began to roll,
And rag'd with inward heat, and threatened war."
Ovid's Metamorphoses.

Although there are a number of opinions as to just which dragon in legend is represented by Draco, the constellation is a very important one, for one of its stars, a star named Thuban, was at one time our Pole Star. Indeed, in 2300 B. C. the Pharaohs of Egypt looked up at Thuban as their Pole Star. As their Pole Star! But where was our faithful North Star during 2300 B. C., and how could our earth's pole swing from this point in the heavens to one half the way between the "Guards" on the tiny bowl of the Little Dipper, and Mizar on the crook of the handle of the Big Dipper? This strange phenomenon not only happened but happens regularly, for the earth "reels like a top" as well as "whirls," although the reeling motion is so much slower than the whirling motion that while it whirls once on its axis in a day, it reels around only once in 25,000 years. During this time the earth's axis describes a circle from Thuban, through the present Pole Star, around through Vega and back again. Vega may be easily located for it crosses the zenith in the late evenings of summer, a beautiful bluish-white star of the first magnitude. It will be about 11,500 years or about 13,500 A. D. before this blue star will again shine above the northern pole of our earth.

It was not an uncommon thing in olden times to build temples dedicated to the observation of certain stars. It is believed that the great pyramid of Cheops, built 4600 years ago, was so constructed that the light of Thuban, then the Pole Star, would shine down its great stone tube at the time the star was at its lower culmination. Olcott in "Starlore of All Ages" tells us that the idea was to conduct the ray of light from Thuban through the passage opening high up in the side of the pyramid, to the eye of a god hidden far down beneath its foundations. When viewed from the bottom of the tunnel, which ends in a room hollowed out of solid stone, it is said that the mouth appears but little larger than the moon's diameter. It is interesting to note that the pyramid of Cheops is the mightiest structure the world has ever seen. According to Herodotus, 100,000 men were employed constantly on this work for 20 years. But the rays of Thuban can no longer shine down the 380 feet of stone tube to light the eye of the god hidden in its depths, for the reeling of the earth has caused the tube to be out of the star's line of light. It may happen again in 21,000 years, however—if the pyramid is still there.

In China there is an observatory 4000 years old which Samuel G. Bayne in his little book the "Pith of Astronomy" speaks of visiting. Here is a slanting granite wall in which two eyeholes had been bored for the sole purpose of sighting Thuban.

Changes in the universe are very gradual and although 4000 years seems a long time to the limited mind of a human being, it is but little in comparison to the vast periods of time which must pass before a visible change can be noticed in the heavens. We speak of these years nonchalantly, but astronomers have had to work hard and patiently in order to make such assertions and to back them up with sufficient proof.

Traveling backward in imagination on the circle that our pole has taken 25,000 years to describe in the sky, and again imagining the star which we now see as our Pole Star as the Pole Star of that by-gone era, what a difference we find in the appearance of the earth! Herds of strange and savage animals are scattered here instead of thriving villages and cities, and man, in equally savage state, wanders about the hills and plains alone or in straggling bands. In traveling forward 21,000 years again to the time only 4000 years ago when Thuban, on the coils of the Dragon, shone as our Pole Star, we come to comparatively recent times; civilization on our earth has made great advances, not the least of them being that it has raised its head and has noted that there are not only stars but that the stars differ from one another. Probably during this era the Chinese chose the Dragon for their national emblem.

The principal interest in the constellation of Draco is, of course, the star Thuban. It is interesting to locate this ancient Pole Star which lies on the tail of Draco, just above the handle of the Big Dipper, and reflect that this star was once the hub of the starry universe, with the Big Dipper whirling round and round it in a close circle.