THE WONDERS OF THE SPATIAL UNIVERSE.

Evening Star, Issue 18045, 12 August 1922, Page 2

THE WONDERS OF THE SPATIAL UNIVERSE.

The first thing that interested man was the world outside him; the last thing the world inside him. And in the outside world the -sun and stars were primary. Astronomy was probably the earliest of the sciences.- Ho had to begin with the naked eye. With , it ho could see only some* 6,000 stars. • It was a small universe to the earliest explorers of the earth and sky. But with the invention of the telescope it expanded enormously. It multiplied the power of the eye two-hundred-fold. Photography come to the aid of the telescope, and the star-sown spaces widened out tilt the mind reels back bewildered at their distance. The human mind has gone on inventing instruments wherewith to gather up the light that is streaming about our earth from these star-sown spaces of the heavens. The latest of these eyes is the telescope recently erected at the Mount Wilson Observatory, in California —the largest instrument of the kind in the world. As this is one of the wonderful achievements of the human mind, we may Mve some account of it right hero. » # « ■» The lens is lOOin in diameter. Five tons of glass were needed for its construction. As np melting crucible would hold that amount of glass it was melted in three different ones, and then all wore poured

into one mould and mixed so as to get perfect consistency, for the least bubble or flaw would mar the lines and make It useless. The work was done in the forest of St. Gobain, in the Department of the Aisne, in France, and it was finished before the Great War broke out. It was shipped via Galveston to California. The polishing of the lens was completed there. It had to bo hollowed by polishing till about one ton of the glass was gently scoured away by emery paste and rouge. After years of shaping and polishing a trifling defect was found in one part of the mirror, but such a trifle would have distorted its reflection and rendered useless the calculations. What was to be done? Were the ten patient years of work in the casting to be rendered useless? That could not be endured. So nine months more wore spent in polishing, and at last the flaw was removed and the work finished. But the next problem was to get it up the 6,000 ft of rugged mountain where the observatory was situated. The lens, packed in so’ft mapping and in an airtight chest, was hoisted on a motor waggon, and it started on its zigzag journey uphill. Its safety was watched over by fifteen alert men, who guarded it against any jolt, or stone, or other dangerous thing that might lie in its upward nine miles of a winding course/ Happily all went well, and the precious burden reached the mountain-top and was finally placed in position, and is now gathering into its enormous eye the lights from the vast unknown worlds that have hitherto been hidden from us. It is a wonderful story of achievement. “The foresight, care,and skill,” says the waiter from whom we laavo condensed the foa-egoing account, “ that have carried this great work through to success are a rare example of the persistent search for knowledge which slowly alters the story of mankind. It is always going on, and to these patient seekers after knowledge we owe a debt wo can never pay.” « * « * This wonderful telescope enables us to see nearly half as many more stars as we had previously been able to do. It will show us over 300,000,000 —the only eye on this earth that can reveal to us an extra hundred million. Where, then, are we in the matter of runs and space? Last year Professor White told the Astronomical Society in Dunedin that, travelling at a mile a minute, one would reach the moon in live months, the sun in 178 years, and Neptune, the outermost member of our solar system, in 5,000 years. But to reach the nearest fixed star it would take over forty million years! That gives some indication of the vastness of space. The bow and arrow argument of Lucretius long ago, to logically prove it infinite, gets near confirmation in facts like these. And they go on accumulating. This new telescope adds immensely to their significance. Hitherto attempts to determine the size of our universe have been largely guesswork; but we aro constantly gaining fresh information that enables ns to base our answer in ascertained facts. The astronomers at Mount Wilson, with the aid of this new telescope, tell us “that in the particular universe of stars to which our solar system belongs light would take a million years to travel from one edge of the universe to the other. A little thought and calculation will reveal the astonishing significance of this. Light travels at 186,000 miles a second. A member of the Astronomical Society of France calculates that our universe is nearly six million million million miles across from edge to edge.” And astronomers work out the width of our universe as 5,850,715,600GOO, 000,000 miles. Wo have been speaking of what is called an “island universe.” Astronomers moan by this not the absolute extent of space, hut only “a star system of limited extent occupying only a part of space”—nu island in the great sea of space. How much more there is outside of this island God only knows. We get additional food for wonder when we think of the distances of some of these stars from us. By the telescope at Mount Wilson there has been found and photographed a vast spiral nebula, of unknown billions of miles in diameter, and ha the process of throwing off a new world. The distance of this nebula from our earth is nearly six million million miles. Take, again, what is known as the Magellanic Cloud, so called after its discoverer, the daring navigator, Magellan, But it Is only recently that’ any real knowledge of these stars has been obtained. A hundred thousands have been counted, but there are myriads more uncfi.stinguisbable ou the blaze of light. The Magellanic cluster of stars and sains is also spiral in shape. They are 60,000 light years from us, and when you remember that light takes eight minutes to reach ns from the sun—i.e., about 95,000,000 of miles—we get some idea of the immense distance of the Magellanic Cloud. It works out to about 15,000 million million miles. But Dr Trumpet 1 , of the Lick Observatory, who is one of the astronomers on his way to watch the eclipse of *the sun in September, told a Wellington audience of certain giant stars at such enormous distances as from 36,000 to 200,000 light years. Ho said astronomers were divided in their opinion as to whether these clustei's were beyond the borders of our universe or not. But the size of some of these stars is hardly less astonishing than their distance from us. Bolelgeuze, for example, one of the stare

of the constellation Orion, ha* ft diameter of 260 million miles —that is. more than 300 .times the diameter of the sun—and it would talc© 27 million suns like ours to equal Belelgenao in bulk; and when we remember that this is 1,300,000 times larger than our earth wc get some conception of the enormous size of this star. ff * « • It will be hr order now and here to consider for a little the wonder of light itself. We are so familiar with its effects that its amazing mystery overcomes us like a summer cloud without our special wonder. Hitherto the undulatory theory of light has held the field. But if Professor Einstein’s contention should prove correct wc must go hack again to Newton’s explanation. That was that every beam of light consisted of countless billions of little particles of matter, unthinkably small. Professor Planck, an assistant of Professor Einstein, calculates that a quantum —that is, a single particle—of a beam of light is a 3,000-miUionth of the smallest bit of energy that we can measure. “Unless 3.000 of these quanta fall on our eyes we do not perceive any light at sll. So small are they that 100,000 million million million millions would not weigh a gram. ... A fin© chemical balance will weigh a 700th part of a gram, and, the fcest balance ever made was 100,000 times more sensitive. But to weigh a quantum of light the scale would have to be a thousand million million million times raoro sensitive still.” Professor Einstein’s theory requires further confirmation before it is finally established. And it is hoped that the coming eclipse of the sun in September, for which astronomers and scientists are now preparing, will furnish the requisite data for a definite conclusion one way or the other. Meanwhile we may consider the wonder of light as it appears on the undulatory theory. The wind blows over a cornfield, waving the head's hither and thither; but they stay in their places, fixed by their roots. So with light. But if light is a wave it must travel on something. So came the assumption of what is called ether—a marvellous sort of elastic substance on which the waves of light are home to and from us. Let us think, then, of light, with its attendant ether. * * « » Light travels from the sun to us at the rate of 11,000,000 miles a minute. It is carried by the ether—these light waves —in countless billions. They advance in perfectly straight lines. The different colors are made by the differences in the rate of vibration. But in addition to its direct advance there are countless transverse waves caused by the reflection and refraction from the earth. Yet there is no chaos, no jostling or confusion —everything moving in perfect order and harmony. Were this not so the vision of things would be a blur. Wo have seen the care that had to be taken in regard to the glass of the great telescope. Were the ether imperfect at any point it would throw the whole out of position and jumble’ up the vision. And when we think that the glass is not the 100 inch of the telescope, but as ■wide as fhe universe, what ■ a marvel are this unity and uniformity of movement! Now follow these lines into the little opening of the human eye. Here wo come on wonders beside which these others, great as they arc, pale into iftsignificance. ' In every second hundreds of billions of vibrations (light waves) ai'e passing through that little slit of skin behind which the eye is situated —vibrations from the flowers, trees, plains, mountains, clouds, and the multitudinous things invisible. These are pouring through into the eye in countless numbers every instant we have it open upon the world. # # # » And hero is the amazing thing ; somewhere between tho eye and the grey specks of matter that wo call the brain a power takes hold of these countless billions of light waves, sorts them according to their vibrations, and labels them blue, green, red, yellow, violet, etc., with a swiftness surpassing a lightning flash. For tho pyschologist tells ns that color is uot in things; it is in the mind that looks at them. The colons which take us captive, in the light of the world, the magic of a popny or a rose, or the glory of a sunrise or sunset, are all due to a difference in the vibration of tho ether that carries and distributes the light waves through tho universe. The vibrations reproduce themselves to our consciousness, and, according to the number of them, tho mind in a flash translates and interprets them as the blue of tho sky, the crimsoii of a sunset, the green of a hillside, or tho pink flush of a rose. Nobody can tell how it is done. Nobody can tell how the mere movement of particles of tho grey matter of the brain becomes consciousness and talks of colors that ©harm and captivate with their wonder and beauty. Yet hero between the little opening .slit of the eyes and the mysterious grey matter that constitutes the brain more and greater work is done in every instant of time than that achieved by all the machinery of the world. And it is done with an ease so swift and unconstrained that we are not conscious of it. If this bo tho result of mere chance collocations of .atoms that we call the world and man, wo may as well dismiss the word rationality from the vocabulary of human speech. Lord Kelvin once asked Liebig, the famous chemist, if ho believed the grass and flowers grew by mere chemical forces. And Liebig replied : “ No, no more than I believe a hook of botany describing them could grow by chemical forces.” The old Hebrew poet ages ago was probably as near the meaning and significance of it all when lie spoke of the Eternal covering Himself with light as with a- garment.