A SICK MOON

Evening Post, Volume CX, Issue 69, 18 September 1930, Page 26

A SICK MOON

CHILLS AND FEVER PUMICE WORLD'S TRIALS RECENT DISCOVERIES (Copyright.) Nowhere a web, or .wing, or crawling or moving thing. Everywhere an appalling silence, a thousand times more acute than the desert void of the Sahara. No afterglow, no dawn, no dusk. Objects stand etched, clean-cut studies in black.and white; shadows are sharpedged' as thunder clouds against a blue sky. Gravity pulls down a mountain, and there is do noise, mo dust. Ashes tossed in the air fall back in straight lines more slowly than snow flakes, undisturbed by the faintest breath of breeze. The.sky is dark without a wisp of cloud anywhere. And always in the centre of the heavens glows a great globe, eighty times as massive as the moon.

Is this a description, of nightmare land? Not at all. It is merely an account of how the moon would appear to a human standing on its surface —an account compiled from facts uncovered recent]} when a group of experts in all the physical silences co-operated in an effort to make the moon divulge its secrets. Every device known to the technicians, from the world's largest telescope to the smallest of microscopes, was brought to bear on moonshine. And while the scientists did not get all the information they wanted, they learned a number of new and surprising facts about our heavenly neighbour. A SICK MOON. The committee of distinguished men, appointed several years ago to make this intensive study of the moon, has completed its work, the members have compared notes and their papers are now in the hands of the father of the idea, President Merriam, of the Carnegio l'nstitution,-of Washington. Working both separately and jointly,, these diversely specialised savants enfiladed the moon, and the concerted attack lengthened out into a siege, which was only recently lifted. Yet, while the spoils of victory consist mostly of involved, data, one of the most interesting revelations to the layman is that the moon has a bad ease of chills and fever. To discover the symptoms of this lunar illness, two scientists, employing complicated moon thermometers perfected in the Mount Wilson Observatory, took the temperature of the side of the moon which is always turned to the earth, from moon rise to moon set, continuously every day and night for more than a year. They learned that as soon as sunlight streams across the earth-side of its face the moon's cold countenance is suffused with warmth — gets warmer and warmer until midday it is sizzling hot. Water would boil in the craters, if water were there. Then, as tho sun moves on, shadows colder I than ice and blacker than night creep across the pitted surface, and by midnight the temperature falls as low as 254: degrees below zero, Fahrenheit. I The moon, therefore, cannot bo thought of as the abode of life. Spores, or the seeds of life, may survive a short time in boiling water, but protoplasm in any form would instantly perish in bone-dry heat of 212 degrees, or over. Spores have been found, alive in the snow of Alpine peaks, but they are very rare, and tho climate of tho world's highest mountains is -warm iv comparison with the midnight moon. Where the temperature varies daily between 212 degrees above and 254 degrees bcr low zero life has no chance. WHAT MATTER? .Finding the moon a victim of chills and fever, the astronomers turned their very definite facts over to the experts on voleanism, geology, and physics. Tho latter promptly went to work to diagnose the moon's spasms in brder to learn its composition. Already they had granted that the moon could not be made of anything that would melt, because,every pock-mark in that stony face has been there since the first telescope was invented. It would have to be some kind of matter which would become boiling hot in sunshine and eight times as cold as ice in the shade. It would have to take in end give out 406 degrees on the thermometer every day without being seriously affected. Previously the amount of radiation delivered by the sun upon the moon's disc had been determined by Dr. Edison Pettito, of the Mount Wilson, staff. Knowing' that only r:iys with wave Jcngl.lis longer than ultra-violet rays can heat objects, he calculated exactly how much radiant energy struck every square milo of the moon's surface daily, for there were no clouds, no haze, no dust in the air—:n.o atmosphere to interfere with the flow of sunlight.; Lunar weather never changes save for a short time during eclipses. PUMICE. The physicists who undertook to find what has the same conductivity and convectivity as moon substance were Dr. Paul Epstein and Dr. P. E. Wright. Both had at hand the findings already reported by geologists and volcanists, together with information from other members of the committee; Working separately, the physicists- expert mented with various earthly materials, but nothing like sand, or granite, or lead, or lava, would take in and give out heat at exactly the moon's rate. At length they tried pumice—the granular, spongy framework of the foam which forms on lava and- hardens as the bubbles of gas in it escape. It proved to be moon material. For, in tho presence of the same amount of solar radiation as that received at the moon's surface, it heated, and in the absence of the radiation, it cooled. In other words, its conductivity and convectivity tallied-with the results the astronomers had obtained from tho moon. If a great jnuniee-covcred ball were substituted for the moon, they concluded, it would also have chills and fovcr —bo boiling hot at noon and several times colder than . tho North Pole at midnight. Volcanoes, it appears, have deeply dusted the pock-marked fiicc of the man in the moon with pumice. The violence of those ancient volcanoes is seen in the size of their craters, somo of which are seventy miles across —ten times the diameter of the earth's largest crater. When those great craters were in wild eruption, what a sight the "moon must have been! In the sunrise and sunset motion pictures, taken at the Mount Wilson Observatory, white light creeps across the craters 'in tho morning, and black shadows creep back during tho afternoon, without the slightest twilight, shimmerings along the edges. GIANT MUSCLES. If a man landed on the moon he would be both deaf and dumb. He might open his mouth, but no souud could come from his throat, because vibrating throat muscles produce sound waves only in air. Surrounded by a vacuum, his capillaries would burst and his eyes pop out. For, at fifteen pounds to the inch, a man on the earth is surrounded by about 35,000 pounds of air pressure, and his body has been built in adaptation to that pressure. Take the pressure away, and he would fare like a deep-sea fish suddenly raised to the surface. But, if he were strait-jacketed

in clothes which kept him from exploding, and carried his own supply of air, he would find himself performing miracles. At every stride he would step fifteen feet; and, if he should stumble over a precipice, instead of falling sixteen feet in a second, he would fall only two feet eight inches. The mighty muscles 'which man has developed to handle weights against the powerful pull of earth's surface gravitation would enable him to out-jump a kangaroo and play ball with boulders. He would weigh only ono-sixth as much ■is he weighed upon the earth, yet he would be six times stronger, because the pull of gravity, which determines weights and measures physical ability, is only one-sixth as strong on the moon as on the earth.