COSMIC RADIATION.

Auckland Star, Volume LXIV, Issue 88, 15 April 1933, Page 6 (Supplement)

COSMIC RADIATION.

MYSTERY - STILL JEALOUSLY

GUARDED.

ASCENT INTO STRATOSPHERE.

RESULTS OF EXPERIMENTS.

(By PROFESSOR AUGUST? PICCARD)

Althougft 'our studies of the records and observations so carefully and laboriously made by Max Cosyns and myself on our second flight into the stratosphere in August are not yet com•plete, wo have already learned enough through our a'nalyses to confess with a clear conscience that nothing has been proved so far: cosmic radiation still jealously guards Its secret. - We ascended atiout 53,672 ft above sea level, exceeding the altitude of my previous flight by more than 1000 ft, but many more balloon expeditions will have to be undertaken, and especially at least one successful ascension in the polar regions, where the effects of the mag-1 netic waves may be observed. We are now in a position, however, as a result of the observations m Aurnist, to check up on one hypothesis evolved after my first fliglxt of the year before. That is: Cosmic radiation does not come from cosmic space at all, but is produced in the uppermost strata of the earth s atmosphere. . I know it is difficult to explain m terms easily understandable to the layman the theory of cosmic radiation. People ask: "What are cosmic rays and what is cosmic radiation?" My answer is simple: "We do not know. Charting Space. From the purely unscientific or mechanical viewpoint of practical aeronautics it can be said, that we have learned to chart uninhabited space, space which sooner or later may become the "stratoways" of future transportation and communication, much as the ancient-, mariners first learned to chart untravelled seas. The stratosphere, into which a short while ago all things that breathe dared not venture without' grave risk to life, now can be visited comparatively easily and absolutely safely. Everyone knows human life cannot exist without artificial respiration at altitudes much above 20,000 ft or 25,000 ft. _ At 53,672 ft it is impossible to without such respiration, both because of the lack of oxygen and the low atmospheric pressure. The human body is made to withstand atmospheric pressures up to 15,000 ft or 20,000 ft altitude. Pressure of half an atmosphere can be borne comfortably. This is about 17,400 ft. Heights between 22,000 ft and 27,000 ft' have been borne without artificial respiration. Over that man cannot-go unless enclosed in an airtight cabin provided with oxygen and protected from cold or heat. Unanswered Questions. But to get back to cosmic radiation, the study of which was the primary object of the ascent, and to sum up <s>nly the principal questions which remain unanswered thus far. Where are cosmic raya produced? How are cosmic rays produced? What is the nature of cosmic radiation ? ... The theoretical physicist undoubtedly approaches .an answer to these questions onca the experimenter has succeeded, with a high degree of accuracy, in determining some of the-properties of . cosmic rays. Cosyns and I sought to determine the intensity and so far as possible the direction from which cosmic rays come, at various altitudes in the free atmosphere. In this year's ascent we naturally profited from previous errors. We climbed slowly, under perfect conditions, Cosyns busying himself with his instruments almost as soOn as we had left the ground. We remained aloft as long as necessary, although we could easily and comfortably have remained up longer had there not been the prospect of drifting out' over thd Adriatic Sea or the Mediterranean. Consequently, it might be said that our aeronautic objectives were fully attained. T-n our study of cosmic radiation we reasoned that if cosmic radiation reaches ns out of cosmic space, and if 'it is homogeneous, an observer in an ascending balloon should notice an increase in reactions according to an immutable, simple law —the relative increase in radiation must be proportional to the quantity of air traversed by the ascending balloon. In other radiation most increase by a certain constant percentage of its momentary value for each centimetre the barometer dtops. Whore are Cosmic Rays Produced ? The results of our, observations were very surprising. In the higher altitudes we found neither a greater nor any constant increase. We, found rather a smaller increase than would be required by the fulfilment of what we had regarded as immutable law. This truth cannot to-day be challenged or disputed. Professor Regener, who sent unoccupied recording balloons into far higher altitudes than we Were able to penetrate, discovered this fact during the summer. His balloons climbed to an altitude which the barometer measured ■with a pressure of 25 m.m. At our highest point the mercury tube "showed 72.5 m.m. by the long barometer and 74 m.m. by lie short barometer. In my first ascent, when we reached 15,780 meters altitude, the barometer registered 75.2 m.m. Our direct readings from the Fnrs confirmed the deductions made by Professor Regener from his recording balloon reports. Two theories appear to me as most plausible in seeking to explain the phenomena. First, as I said before, cosmic radiation does not come from cosmic space, as we had at first believed, but is produced in the uppermost strata of the earth's atmosphere. Second, the hard and most penetrating portions of cosmic radiation do come from cosmic space, but the softer, strongly-ionised components are a'sort of secondary radiation produced by the ' impact of the hard rays on the air molecules. If the second theory is the correct one, the abscnce of the softer components can be explained by assuming that the cosmic rays are produced in the extremely attenuated matter of cosmic space, or else by assuming that the earth's magnetic field causes a deviation of the soft components toward the magnetic poles of our planet, where they are awaiting the visit of another Fnrs expedition. I hope that very soon investigations into the stratosphere in the Hudson Bay region will be undertaken. Valuable information should bo obtained to support or break down this theory. Naturally such an ascent will be difficult and feL: v

dangerous, and should be undertaken by scientists acquainted with and acclimated to sub-polar conditions. The balloon might easily drift out over the polar ice cap or descend in the depths of the Canadian wilderness. The crew must be equipped and prepared to make its way back to civilisation. Our second objective was the determination of the direction of cosmic rays. To our surprise we discovered, when in the stratosphere, that our tests indicated there is no directional effect noticeable in recording cosmic rays. Whether the tube wa3 vertical or horizontal the number of rays' recorded over a given period was the same. They were on the average constant within a margin of about one per thousand. Complete absence of earthly noises, which do not penetrate the stratosphere, made the most delicate observations possible. How can we explain this pheomenon? To my mind it indicates that cosmic radiation is produced in the atmospheric strata . where the Fnrs was suspended—above, below and on all sides of us. To a person on the earth's surface cosmic radiation certainly comes from above, and has a distinct directional tendency, like rain pouring from the clouds. In the stratosphere we noticed that cosmic radiation comes to the observer from all directions at once and uniformly. The physicist Kolhorster, working with testa and holding theories quite different from ours, evolved the same hypothesis several months earlier. Unfortunately, however, for the hypothesis we have enunciated, it is not the only one which can be advanced to explain the absence of any directional characteristics of cosmic radiation in the stratosphere. Various other reasons could be given or suppositions advanced with equal force in. explanation of the phenomenon we observed. Many further tests must be made before we can either discard or accept the theory. Riddles Still Unsolved. As I said before, we can declare with entire honesty and sincerity that at present nothing definite has been proved. Cosmic radiation guards well its mysteries. But nevertheless a hypothesis which would have been unthinkable a few months ago must be recognised, and enters into competition with all other hypotheses—that of the statospheric origin of cosmic radiation. The tempting feature of the new hypothesis is that it seems easily to explain why this mysterious radiation is independent of the earth's direction in space and is not a definite function, therefore, tof either sidereal or solar time. In conclusion I would like to repeat that the experiments thus far have not been without appreciable results, but that much is yet to be done before we call even begin to answer the many riddles that confront us in our quest of knowledge of cosmic radiation. To physicists like myself and my colleagues Cosyns and Kipfer, it is a Sublime feeling to know that we are approaching a solution and that we may soon peer behind the veil of mysteries. Whatever our future discoveries may be, wherever our quest may lead, it is certain there will be great strides forward in the near future. —(N.A.N.A.)