WONDERS OF SPACE

Taranaki Daily News, 13 July 1935, Page 1 (Supplement)

WONDERS OF SPACE

JEAN’S LATEST BOOK

(By the

Rev. B. Dudley,

F.R.A.S.)

Sir James Jeans in his Royal Institution lectures, during Christmas, 1933, "must have startled many of his hearers into interest in the starry skies. Children from eight years of age to veterans of more than 80 were attracted, and he interested them all. The lectures have been published in book form under the title, “Through Space and Time.” They are as easy to read as the stories of Charles Dickens, and the illustrations accompanying the chapters as illuminative as the sketches of “Phiz” and others, who gave so much additional life to the Dickens stories. Many of them are quite fresh, being specially prepared for the •book. None of them is a mere appendage to the volume.

Sir James takes his readers through space on a rocket, stopping in turn to investigate air, sky, moon, planets, sun, stars and neublae, first having, along with them, explored the earth, itself from the moment of its formation bn the coils of; gaseous matter drawn out of the sun •by a passing star, through its subsequent aeon-long evolution, until life appeared, and finally man. We see the •continents separating from one another, each becoming, as it were, a floating island, since down at and near the earth’s core matter is in a plastic condition. “The earth,” he states, “started •its existence in a hot mass of gas; it was born in a cataclysm which would probably stir up its various constituent substances, and mix them up, even if •they were not thoroughly mixed already. Then, as peace and calm succeeded to turmoil and confusion, the lighter substances would begin to float upwards, while the heavier would sink towards the centre of the earth,” At last begins •liquifactlon, and after this the earth starts to solidify. Mountains are pushed up and depressions formed in the surface layers. Mountains stand-up above the level of the land, says .the author, for just the same reason that ships stand up above the level of the sea—because they float, not, indeed, in water, but in plastic earth matter, which behaves like a liquid. He traverses Wegener’s theory that all the land which stood out above the sea some hundreds of millions of years ago could be fitted . together' to'make one continuous continent, which would then cover about a third of the face of the globe. In the chapter on the atmosphere, Sir James dealt with ancient and modem •theories, considers the operation of radio waves, and the Kennelly-Heaviside and Appleton layers of gas at. considerable heights, and the lower D layer, not more than 25 or 30 miles high. He shows what can be learned of the air by the passage through it of light and sound, the fall of meteorites, etc. Clouds and fogs, stonrfls and calms, auroral displays and •magnetic phenomena are all made as interesting as a novel. 1

In the chapter on the sky, Jeans describes the appearance of the heavenly •bodies as ' seen upon its background. Ancient beliefs and modern knowledge •are compared and contrasted. The earth’s long wobble of 26,000 years is explained as giving rise to certain changes in the positions of the constellations. Why do the moon, Mercury and Venus go •through “phases?” Why do shooting stars “shoot?” These questions end many more are. expounded to the satisfaction of the most exacting reader. Dealing with the moon, the author has a delightful chapter, the reason why this •body has no atmosphere, no water, no vegetation, no blue sky, no life, being given in most convincing terms. Why, on the other hand, it is so pitted and riddled with holes and craters, and why it keeps always one face directed to the earth, so that we can never see its other side, are other questions just as lucidly accounted for.

The planets, their origin, composition, history and possible destiny are brought under review one by one. The evidence <we have is against the habitability of any planet in the solar system except the earth, though Mars and Venus come ■nearest to possessing the conditions required for life. How Saturn got its rings, how the planets got their moons,' and why the earth’s satellite is so bigin-proportion ■to its primary, afford themes dor .consideration in this chapter on planets. So do comets, which are often connected with remoter planets. The sun’s story is made to be .of immense interest to the reader as he is told what it is made of, and how sunspots behave and give rise to mighty flames shooting up to hundreds or hundreds of thousands of miles in height. ■Photographs of one of these upheavals, 567,000 miles in length, are given. It is ■also explained how the spectroscope discovered in the suh those elements found ■in the earth—hydrogen, oxygen, nitrogen, iron, copper, gold and so forth. Indeed, “the universe appears to be built of the same kinds of bricks throughout,” we are reminded. This last statement is borne out in the enthralling chapter on the stars, which •are just “other suns than ours.” Exact modem measurements show that the nearest stars to us are almost exactly a million times as distant as the nearest planets, such as Venus or Mars. “We 'have already seen,” the author states, “how sparsely scattered the planets are in the solar system; it now appears that space is even more empty of stars than the solar system is of planets. Five fruits placed in the five continents of the earth —an apple in Europe, a pear in Asia, a cherry in America and so on—will give us a scale model showing the relation •between the sizes of the stars and their distances from one another.” If we take six wasps and set them flying blindly about in a cage 1000 miles long, 1000 miles broad and 1000 miles high, he says, we shall again have a model of the distance of the stars. The wasps will not bump into one another,- 1 or even pass Twa r to one another, at very frequent intervals. Here it is that Jeans expounds the likely theory that the planets were formed by the influence of another star passing our sun long ago. “It is most probably only when stars do this that planets like our earth come into existence. . . . For this reason, the birth of planets must be a rare event, and also, since the universe has not existed for ever, planets themselves must be very rare; . . .at the most favourable computation, it seems likely that only about one star in every hundred thousand can have a family of planets to take care of.” The last chapter, that on the nebulae, is as luminous in description as the nebulae in themselves, as seen from our distance, are dull. The two nearest of these objects are both about 800,000 light years distant. The faintest, as photographed in the world’s largest telescbpe, is 140,000,000 light years away. The significance of these bodies is. dealt with, as also is the unbelievably stranger fact that these far off cosmic systems seem to be flying apart at (in some cases) the rate of 15,000 miles a second—a million times the speed of an express train. Just as the stars are other suns than our own; so the nebulae arc other galaxies than ours—“other universes,” to employ a term which is liable to misunderstanding.