THE FLAMING MYSTERY.

Auckland Star, Volume LXII, Issue 233, 1 October 1932, Page 7 (Supplement)

THE FLAMING MYSTERY.

SUN AND SUNSPOTS. ENERGY BEYONI> CONCEPTION WHEN WILL THE CURTAIN FALL? What is a sunspot? You look at a spot through a. telescope and distinguish a central purplish patch. "Umbra," the astronomer calls it. Fringing it is the lighter "penumbra," a splendid structure of curling plumes and graceful filaments. Bridges of vapour sometimes arch the umbra and marvellous veils and clouds hover over it. From day to day structure and texture change. That black umbra— what is it? A rent in the dazzling surface of the sun, a hole through which we peer into an awful inferno? Astronomers thought so once. Now the spots are recognised as elevated, spinning funnels, flaming tornadoes, vortices out of which fiercely glowing gases are tossed to spread over the solar surface and to endure for days, weeks, months. The average one lasts no more than a week or two, but one was observed for a year and ■ a half. And the size! The earth could be dropped into most spots and never be missed. It is a small spot that measures less than the earth's diameter of 8000 miles. And there have been spots with a span of 145,000 miles. The sun has a surface temperature of at least 10,000 degrees Fahrenheit. At the centre, Eddington liolds, -the temperature must be 70,000,000 degrees. A speck of iron heated to the calculated temperature of the sun's interior would radiate enough heat to blast all life within a radius of 1000 miles. Ample Time for Geologists. The atoms in the sun are ia effect bottles of energy spilled throughout the universe in the form of light and heat. Yet so enormous is the sun's supply and so great is the energy content of each bottle that even after ihaving blazed for at least eeven or eight thousand million years—Jeans' estimate of the sun's age—there is still enough left for many more thoxisands of million years to come. The geologists now have all the time they demand to explain how the earth acquired its rocks, seas and continents. Jt cannot be denied that there is some guessing about these multi-millions K>f years, but it is guessing with a solid foundation, based as it is on the rela* tion between the eun's luminosity and its weight. The heavier a star, the brighter will it be. But the ratio between weight and luminosity is not what might, be supposed. If the sun were only half as massive as it is, it would radiate not one-half as much light and heat, but one-eighth. Similarly, if it were twice as heavy as it is, it would ehino not twice but eight times as brightly. About two thousand million years ago the sun had 1.00013 times its present weight. Eight thousand million years ago, when the earth was born, the sun must have been much as it is now. To the modern astrophysicist the sun is still young, though to the Victorians it was guttering to its end. ■ It is because of the relation of mass to brightness that both Jeans and Eddinjton agree on the siyi's age. Go back, say, 7,000,000,000,000 years, and the sun becomes impossibly heavy— about 100 times ae heavy as it is now. An age of seven or eight thousand million years gives just the right weight and brightness. But how does Jeans know what is the right brightness? By comparing the sun with other stars of the same type. It turns out that each square inch of the sun's surface radiates about 50 horse-power, which is generated by thp annihilation of matter at the rate of about a twentieth of an ounce in a century. For the sun as a whole this insignificant amount adds up to more than 4,000,000 tons a second. Tomorrow the sun will weigh 300,000,000,000 tons 'less than it does to-day. Yet it is so huge that it will shine for at least fifteen million million years longer. Falling Into Frozen Space. Until Jeans aud Eddingtoii gave us these new views, the sun was supposed to be a tremendous glowing ball of gae. But Jeans showed that a gaseous sun would either collapse or explode. He imagines tho core to be liquid. Only the outer wrappings are gaseous in the true sense. At the core, he holds, there aro superactive atoms much heavier than uranium or radium. We have 92 elements on the earth; if Jeans is right, ' there may be more deep in the solar core. i Since the sun is radiating itself away •: and losing 360,000,000,000 tons every ' day, its gravitational clutch on the | earth must be slackening. Jeans has calculated that we are spiralling from the sun at the rate of little more than a yard in a century. In a million million years we shall be 101,530,000 instead of 82,300,000 miles away. By that time the sun will have lost 6 per cent of its present heat through, radiation, and its energy-producing capacity will have been reduced by 20 per cent. The terrestrial temperature will be 54 degrees Fahrenheit lower than it is now, and the earth will be reduced to an icy >all swimming through space. If they iave not evaporated long before then, th.e oceans will be frozen masses. Map's Brief Hour in Eternity. Will man have perished? He has the power of creating an artificial environment for himself. Ho knows how to heat his homes and his factories. More than glacial cold is needed to exterminate him. But, as the earth drifts away with the passing of the centuries, a temperature that was once glacial and tolerable with the aid of science will approach the absolute zero of interstellar space. The curtain falls when the atmosphere is precipitated first in blizzards of carbon dioxide and finally in a downpour of liquid air. No inventive ingenuity can stave off death. AftVr having stumbled into a universe that v/as never destined for life, man wfl be blotted out by forces that were hostile to him from the beginning of time and over which he triumphed for a brief hour, "leaving the universe," in Jeans' words, "as though he had never been."