The nearest star is the sun. It took the human race quite a few thousand years to discover this fact, for no objects could seem more unlike than the dazzling, burning sun and the coldly scintillating stars. It is the sun’s extreme closeness that makes the difference, and makes the sun so overwhelmingly important to us.
The amount of energy we receive from this nearest star is enormous, and the earth itself intercepts only a minute fraction of the sun’s rays; most of the energy goes rushing past into space. If the sun were made of coal, for example, it would have burnt itself out in a couple of thousand years. Astronomers racked their brains and decided that the sun obtained its energy from its slow contraction under gravity.
But if the sun were contracting, it must once have been bigger, and calculations showed that 50 million years earlier it would have embraced the earth. This obviously set a limit to the age of the earth. Geologists pointed out, however, that 50, 100, even 500 million years was not long enough for the changes our planet has seen - mountains worn away, chalk beds kilometers thick that had been laid down on the beds of vanished seas. They told the astronomers to look for a few more noughts. Not until the discovery of radioactivity did astronomers realize that gigantic stores of energy were locked up in the atoms themselves, and that the sun was able to tap that energy, which was sufficient to keep it shining for thousands of millions of years. But how does the sun tap the energy of matter?
Many of the ordinary elements are present in the sun. Some elements - radium, for example - are naturally unstable and continuously give out energy until they have decayed into less spendthrift substances such as lead. But radium could not account for such a vast generation of power over so long a period; the sun must have learnt the secret of releasing energy from “ordinary” matter. The first major clue to that secret came in 1868, when the newly developed spectroscope revealed an element in the sun not yet discovered on earth. The new element was named “helium,” and after an intensive search it was found in our atmosphere in minute quantities.
We know now that helium is the ash left when atoms of hydrogen are fused in the furnace of the sun. This type of “burning” is infinitely fiercer than ordinary combustion; it is an atomic rather than a chemical process, and takes place deep within the sun, under pressures and temperatures beyond imagination. Helium and hydrogen are vastly more abundant in the sun than all the other elements put together. Every second about four million tons of matter are converted into energy; to equal this output, we would have to explode 80,000 coal trucks full of TNT every second. The released energy batters its way up to the surface of the sun, hundreds of thousands of kilometers above. Then, in the form of light, heat and other radiations, it spreads out into space.
No man has ever seen the sun, or ever will. Only a small part of its radiation - narrow band of visible light - leaks down through the earth’s atmosphere, which filters out the ultra-violet and X-rays that would otherwise continually bombard us. At times the sun sends out sudden spurts of ultra-violet light that cause such intense electrification of the upper air that long-distance radio circuits are disrupted. In recent years it has been possible to make computer-simulated movies of the surface of the sun, and by speeding them up several hundred times to project on the screen the life story of cataclysmic solar events which may occupy hours of time and multiple millions of cubic kilometers of space. Some of these movies are awe-inspiring; they show immense fountains of glowing gases spurting to heights of a hundred thousand kilometers; bridges of incandescent gases, which could span a dozen earths, forming and crumbling; exact replicas of A-bomb bursts - but a thousand times as large - shooting up into space.
Watching these movies, you see the action of forces completely beyond our understanding. A slanting jet of incandescent gas, for example, will shoot out on a long, flat trajectory, reach its apex, and then whip back along its original path - as if a shell at the peak of its flight decided to return to the gun. And sometimes, thousands of kilometers above the sun’s surface, cascades of glowing matter will pour down from no apparent source, as if they were created high in the solar atmosphere.
Since the sun is purely gaseous, it is surprising that its surface is so sharply defined. Seen through the telescope, its edge is a perfect circle. One reason for the sharpness of the sun, edge is its intense gravity, 28 times that of the earth. On the sun an average man would weigh over two tons. Although many stars wax and wane in brilliance, the sun’s output of heat and light has changed little during the course of human history. But what of the future? What will happen when the sun starts to run out of fuel about the, year - A.D 10,000,000,000? The obvious assumption would be that the sun will gradually cool down to a dull red and finally gutter out into extinction. But the obvious assumption is not the correct one. The sun is not cooling down; it is warming up!
As the sun uses up its hydrogen fuel and the helium “ash” accumulates round its core, the rate of reaction will increase. Like a gambler who bets more and more frantically as he approaches the end of his resources, the sun will go out in a final blaze of glory. Within a span of a mere five million years it will increase its brilliance a hundred-fold, melting down the earth and the inner planets into balls of glowing lava. Then it will collapse swiftly to a tiny star only a few thousand kilometers in diameter. It will still be bright, but it will give out little more heat than the full moon does today. The minute star which finally gutters to extinction will not be anything we would recognize as the sun.
|How Great Thou Art...|
So, at least, runs the current theory, but to claim that is an accurate description of what must happen would be rash. Even when we have attained a complete understanding of the processes taking place inside the sun, we cannot be sure that external factors - clouds of interstellar dust into which it may run, for example -may not write new and unexpected chapters in its history. At any rate, we need not worry about the sun blowing up, or going out by ‘natural causes’, for the next few thousand years – at least scientifically…
How can anyone still doubt the existence and power of GOD ~ SB