Forty Thousand Feet Skyward

If we are to perish eventually by atom blast, we should realize that we also live by it. Nothing in our ordinary lives is commoner than atomic fission. Only a person congenitally and totally blind can honestly say that he has never seen an atomic explosion. For this is what happens on the sun, on a scale so vast that it eludes our ability to visualize, much less comprehend. Were you impressed by the world-shaking column of heat and light that reared itself forty thousand feet skyward over Hiroshima and Bikini? Consider, then, that solar "prominences," flaring half a million miles into space, are commonplace on the mother-star. The calculable--if unimaginable--volume of radiant energy billowing outward into our universe is source and support alike of our planetary existence. Can we capture this power and put it to work? We can and we do.

It has been stored in coal, oil and waterpower. We release it rapidly or slowly, in large or small quantities. We carry it anywhere and everywhere, for any or all of thousands of purposes. Can we capture it directly? Yes! Man, who has tried to harness sun-power since the days of Phaethon, is now on the verge of seeing one of his most cherished dreams fulfilled. Helio-science has become new as tomorrow, with seven-league strides in several important directions. On the common level are new solar houses and practical sunshine traps for domestic use. Corresponding industrial applications are beginning to appear, particularly in the Soviet Union, where a new approach to sun-mirrors has yielded revolutionary results.

On the scientific level, projects have been initiated that, on completion, are going to change human life and living in many ways, and the potentialities of all these studies and developments are measurable only in terms of the sun's importance in our scheme of things. There was wholesome respect for the sun from the very beginning. Ra in Egypt and Phoebus Apollo in Greece are only two of a hierarchy of sun gods as numerous as the tribes of humanity. Physically, the sun appeared to the ancients as a brilliant disk about the size of the moon. Galileo's telescope, and Newton's pioneering spectroanalysis of sunlight, set helioscience on the broad highroad to modern times, along which it has been enlarged and illumined by the work of scientists like Fraunhofer, Einstein and Bethe.

Today's sun is neither god nor moon-sized disk, but a typical star of moderate proportions (as such things go), weighing in the region of 2,000,000,000,000,000,000,000,000,000 metric tons-two octillion. The sun's brightness is the brightness of atomic transmutation. According to H. A. Bethe's widely accepted "carbon cycle" theory, hydrogen atoms are being turned into atoms of helium, in the course of which a part of the sun's mass is "destroyed." The rate of destruction-4,200,000 metric tons per second-seems staggering to us, but the sun can lose weight at that rate and still last five and a quarter trillion years!