Wonders of the Universe—Star Photography—The Infinity of Space.

In another chapter we have lightly touched upon the greatness of the Universe, in the cosmos of which our earth is but an infinitesimal speck. Even our sun, round which a system of worlds revolve and which appears so mighty and majestic to us, is but an atom, a very small one, in the infinitude of matter and as a cog, would not be missed in the ratchet wheel which fits into the grand machinery of Nature.

If our entire solar system were wiped out of being, there would be left no noticeable void among the countless systems of worlds and suns and stars; in the immensity of space the sun with all his revolving planets is not even as a drop to the ocean or a grain of sand to the composition of the earth. There are millions of other suns of larger dimensions with larger attendants wheeling around them in the illimitable fields of space. Those stars which we erroneously call "fixed" stars are the centers of other systems vastly greater, vastly grander than the one of which our earth forms so insignificant a part. Of course to us numbers of them appear, even when viewed through the most powerful telescopes, only as mere luminous points, but that is owing to the immensity of distance between them and ourselves. But the number that is visible to us even with instrumental assistance can have no comparison with the number that we cannot see; there is no limit to that number; away in what to us may be called the background of space are millions, billions, uncountable myriads of invisible suns regulating and illuminating countless systems of invisible worlds. And beyond those invisible suns and worlds is a region which thought cannot measure and numbers cannot span. The finite mind of man becomes dazed, dumbfounded in contemplation of magnitude so great and distance so amazing. We stand not bewildered but lost before the problem of interstellar space. Its length, breadth, height and circumference are illimitable, boundless; the great eternal cosmos without beginning and without end.

In order to get some idea of the vastness of interstellar space we may consider a few distances within the limits of human conception. We know that light travels at the rate of 186,000 miles a second, yet it requires light over four years to reach us from the nearest of the fixed stars, travelling at this almost inconceivable rate, and so far away are some that their light travelling at the same rate from the dawn of creation has never reached us yet or never will until our little globule of matter disintegrates and its particles, its molecules and corpuscles, float away in the boundless ether to amalgamate with the matter of other flying worlds and suns and stars.

The nearest to us of all the stars is that known as Alpha Centauri. Its distance is computed at 25,000,000,000,000 miles, which in our notation reads twenty-five trillion miles. It takes light over four years to traverse this distance. It would take the "Empire State Express," never stopping night or day and going at the rate of a mile a minute, almost 50,000,000 years to travel from the earth to this star. The next of the fixed stars and the brightest in all the heavens is that which we call Sirius or the Dog Star. It is double the distance of Alpha Centauri, that is, it is eight "light years" away. The distances of about seventy other stars have been ascertained ranging up to seventy or eighty "light years" away, but of the others visible to the naked eye they are too far distant to come within the range of trigonometrical calculation. They are out of reach of the mathematical eye in the depth of space. But we know for certain that the distance of none of these visible stars, without a measurable parallax, is less than four million times the distance of our sun from the earth. It would be useless to express this in figures as it would be altogether incomprehensible. What then can be said of the telescopic stars, not to speak at all of those beyond the power of instruments to determine.

If a railroad could be constructed to the nearest star and the fare made one cent a mile, a single passage would cost $250,000,000,000, that is two hundred and fifty billion dollars, which would make a 94-foot cube of pure gold. All of the coined gold in the world amounts to but $4,000,000,000 (four billion dollars), equal to a gold cube of 24 feet. Therefore it would take sixty times the world's stock of gold to pay the fare of one passenger, at a cent a mile from the earth to Alpha Centauri.

The light from numbers, probably countless numbers, of stars is so long in coming to us that they could be blotted out of existence and we would remain unconscious of the fact for years, for hundreds of years, for thousands of years, nay to infinity. Thus if Sirius were to collide with some other space traveler and be knocked into smithereens as an Irishman would say, we would not know about it for eight years. In fact if all the stars were blotted out and only the sun left we should still behold their light in the heavens and be unconscious of the extinction of even some of the naked-eye stars for sixty or seventy years.

It is vain to pursue farther the unthinkable vastness of the visible Universe; as for the invisible it is equally useless for even imagination to try to grapple with its never-ending immensity, to endeavor to penetrate its awful clouded mystery forever veiled from human view.

In all there are about 3,000 stars visible to the naked eye in each hemisphere. A three-inch pocket telescope brings about one million into view. The grand and scientifically perfected instruments of our great observatories show incalculable multitudes. Every improvement in light-grasping power brings millions of new stars into the range of instrumental vision and shows the "background" of the sky blazing with the light of eye-invisible suns too far away to be separately distinguished.

Great strides are daily being made in stellar photography. Plates are now being attached to the telescopic apparatus whereby luminous heavenly bodies are able to impress their own pictures. Groups of stars are being photographed on one plate. Complete sets of these star photographs are being taken every year, embracing every nook and corner of the celestial sphere and these are carefully compared with one another to find out what changes are going on in the heavens. It will not be long before every star photographically visible to the most powerful telescope will have its present position accurately defined on these photographic charts.

When, the sensitized plate is exposed for a considerable time even invisible stars photograph themselves, and in this way a great number of stars have been discovered which no telescope, however powerful, can bring within the range of vision. Tens of thousands of stars have registered themselves thus on a single plate, and on one occasion an impression was obtained on one plate of more than 400,000.

Astronomers are of the opinion that for every star visible to the naked eye there are more than 50,000 visible to the camera of the telescope. If this is so, then the number of visible stars exceeds 300,000,000 (three hundred millions).

But the picture taking power of the finest photographic lens has a limit; no matter how long the exposure, it cannot penetrate beyond a certain boundary into the vastness of space, and beyond its limits as George Sterling, the Californian poet, says are—

"fires of unrecorded suns
That light a heaven not our own."

What is the limit? Answer philosopher, answer sage, answer astronomer, and we have the solution of "the riddle of the Universe."

As yet the riddle still remains, the veil still hangs between the knowable and the unknowable, between the finite and the infinite. Science stands baffled like a wailing creature outside the walls of knowledge importuning for admission. There is little, in truth no hope at all, that she will ever be allowed to enter, survey all the fields of space and set a limit to their boundaries.

Although the riddle of the universe still remains unsolved because unsolvable, no one can deny that Astronomy has made mighty strides forward during the past few years. What has been termed the "Old Astronomy," which concerns itself with the determination of the positions and motions of the heavenly bodies, has been rejuvenated and an immense amount of work has been accomplished by concerted effort, as well as by individual exertions.

The greatest achievements have been the accurate determination of the positions of the fixed stars visible to the eye. Their situation is now estimated with as unerring precision as is that of the planets of our own system. Millions upon millions of stars have been photographed and these photographs will be invaluable in determining the future changes and motions of these giant suns of interstellar space.

Of our own system we now know definitely the laws governing it. Fifty years ago much of our solar machinery was misunderstood and many things were enveloped in mystery which since has been made very plain. The spectroscope has had a wonderful part in astronomical research. It first revealed the nature of the gases existing in the sun. It next enabled us to study the prominences on any clear day. Then by using it in the spectro-heliograph we have been enabled to photograph the entire visible surface of the sun, together with the prominences at one time. Through the spectro-heliograph we know much more about what the central body of our system is doing than our theories can explain. Fresh observations are continually bringing to light new facts which must soon be accounted for by laws at present unknown.

Spectroscopic observations are by no means confined to the sun. By them we now study the composition of the atmospheres of the other planets; through them the presence of chemical elements known on the earth is detected in vagrant comets, far-distant stars and dimly-shining nebulae. The spectroscope also makes it possible to measure the velocities of objects which are approaching or receding from us. For instance we know positively that the bright star called Aldebaran near the constellation of the Pleiades is retreating from us at a rate of almost two thousand miles a minute. The greatest telescopes in the world are now being trained on stars that are rushing away towards the "furthermost" of space and in this way astronomers are trying to get definite knowledge as to the actual velocity with which the celestial bodies are speeding.

It is only within the past few years that photography has been applied to astronomical development. In this connection, more accurate results are obtained by measuring the photographs of stellar spectra than by measuring the spectra themselves. Photography with modern rapid plates gives us, with a given telescope, pictures of objects so faint that no visual telescope of the same size will reveal them. It is in this way that many of the invisible stars have impressed themselves upon exposed plates and given us a vague idea of the immensity in number of those stars which we cannot view with eye or instrument.

Though we have made great advancement, there are many problems yet even in regard to our own little system of sun worlds which clamor loudly for solution. The sun himself represents a crowd of pending problems. His peculiar mode of rotation; the level of sunspots; the constitution of the photospheric cloud-shell, its relation to faculae which rise from it, and to the surmounting vaporous strata; the nature of the prominences; the alternations of coronal types; the affinities of the zodiacal light—all await investigation.

A great telescope has recently shown that one star in eighteen on the average is a visual double—is composed of two suns in slow revolution around their common center of mass. The spectroscope using the photographic plate, has established within the last decade that one star in every five or six on the average is attended by a companion so near to it as to remain invisible in the most powerful telescopes, and so massive as to swing the visible star around in an elliptic orbit.

The photography of comets, nebulae and solar coronas has made the study of these phenomena incomparably more effective than the old visual methods. There is no longer any necessity to make "drawings" of them. The old dread of comets has been relegated into the shade of ignorance. The long switching tails regarded so ominously and from which were anticipated such dire calamities as the destruction of worlds into chaos have been proven to be composed of gaseous vapors of no more solidity than the "airy nothingness of dreams."

The earth in the circle of its orbit passed through the tail of Halley's comet in May, 1910, and we hadn't even a pyrotechnical display of fire rockets to celebrate the occasion. In fact there was not a single celestial indication of the passage and we would not have known only for the calculations of the astronomer. The passing of a comet now, as far as fear is concerned, means no more, in fact not as much, as the passing of an automobile.

Science no doubt has made wonderful strides in our time, but far as it has gone, it has but opened for us the first few pages of the book of the heavens—the last pages of which no man shall ever read. For aeons upon aeons of time, worlds and suns, and systems of worlds and suns, revolved through the infinity of space, before man made his appearance on the tiny molecule of matter we call the earth, and for aeons upon aeons, for eternity upon eternity, worlds and suns shall continue to roll and revolve after the last vestige of man shall have disappeared, nay after the atoms of earth and sun and all his attending planets of our system shall have amalgamated themselves with other systems in the boundlessness of space; destroyed, obliterated, annihilated, they shall never be, for matter is indestructible. When it passes from one form it enters another; the dead animal that is cast into the earth lives again in the trees and shrubs and flowers and grasses that grow in the earth above where its body was cast. Our earth shall die in course of time, that is, its particles will pass into other compositions and it will be so of the other planets, of the suns, of the stars themselves, for as soon as the old ones die there will ever be new forms to which to attach themselves and thus the process of world development shall go on forever.

The nebulae which astronomers discover throughout the stellar space are extended masses of glowing gases of different forms and are worlds in process of formation. Such was the earth once. These gases solidify and contract and cool off until finally an inhabited world, inhabited by some kind of creatures, takes its place in the whirling galaxy of systems.

The stars which appear to us in a yellow or whitish yellow light are in the heyday of their existence, while those that present a red haze are almost burnt out and will soon become blackened, dead things disintegrating and crumbling and spreading their particles throughout space. It is supposed this little earth of ours has a few more million years to live, so we need not fear for our personal safety while in mortal form.

To us ordinary mortals the mystery as well as the majesty of the heavens have the same wonderful attraction as they had for the first of our race. Thousands of years ago the black-bearded shepherds of Eastern lands gazed nightly into the vaulted dome and were struck with awe as well as wonder in the contemplation of the glittering specks which appeared no larger than the pebbles beneath their feet.

We in our time as we gaze with unaided eye up at the mighty disk of the so called Milky Way, no longer regard the scintillating points glittering like diamonds in a jeweler's show-case, with feelings of awe, but the wonder is still upon us, wonder at the immensity of the works of Him who built the earth and sky, who, "throned in height sublime, sits amid the cherubim," King of the Universe, King of kings and Lord of lords. With a deep faith we look up and adore, then reverently exclaim,—"Lord, God! wonderful are the works of Thy Hands."