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BACKGROUND OF SPACE EXPLORATION
PEOPLE the world over speak of the "Space Age" as beginning with the launching of the Russian Sputnik on 4 October 1957. Yet Americans might well set the date back at least to July 1955 when the White House, through President Eisenhower's press secretary, announced that the United States planned to launch a man-made earth satellite as an American contribution to the International Geophysical Year. If the undertaking seemed bizarre to much of the American public at that time, to astrophysicists and some of the military the government's decision was a source of elation: after years of waiting they had won official support for a project that promised to provide an invaluable tool for basic research in the regions beyond the upper atmosphere. Six weeks later, after a statement came from the Pentagon that the Navy was to take charge of the launching program, most Americans apparently forgot about it. It would not again assume great importance until October 1957.
Every major scientific advance has depended upon two basic elements, first, imaginative perception and, second, continually refined tools to observe, measure, and record phenomena that support, alter, or demolish a tentative hypothesis. This process of basic research often seems to have no immediate utility, but, as one scientist pointed out in 1957, it took Samuel Langley's and the Wright brothers' experiments in aerodynamics to make human flight possible, and Hans Bethe's abstruse calculations on the nature of the sun's energy led to the birth of the hydrogen bomb, just as Isaac Newton's laws of gravity, motion, and thermodynamics furnished the principles upon the application of which the exploration of outer space began and is proceeding. In space exploration the data fed back to scientists from instrumented satellites have been of utmost importance. The continuing improvement of such research tools opens up the prospect of greatly enlarging knowledge of the world we live in and making new applications of that knowledge.
In the decade before Sputnik, however, laymen tended to ridicule the idea of putting a man-made object into orbit about the earth. Even if the feat were possible, what purpose would it serve except to show that it could be done? As early as 1903, to be sure, Konstantin Tsiolkovskiy, a Russian scientist, had proved mathematically the feasibility of using the reactive force that lifts a rocket to eject a vehicle into space above the pull of the earth's gravity. Twenty years later Romanian-born Hermann Oberth had independently worked out similar formulas, but before the 1950s, outside a very small circle of rocket buffs, the studies of both men remained virtually unknown in the English-speaking world. Neither had built a usable rocket to demonstrate the validity of his theories, and, preoccupied as each was with plans for human journeys to the moon and planets, neither had so much as mentioned an unmanned artificial satellite. Indeed until communication by means of radio waves had developed far beyond the techniques of the 1930s and early 1940s, the launching of an inanimate body into the heavens could have little appeal for either the scientist or the romantic dreamer. And in mid-century only a handful of men were fully aware of the potentialities of telemetry.
Of greater importance to the future of space exploration than the theoretical studies of the two European mathematicians was the work of the American physicist, Robert Goddard. While engaged in post-graduate work at Princeton University before World War I, Goddard had demonstrated in the laboratory that rocket propulsion would function in a vacuum, and in 1917 he received a grant of $5,000 from the Smithsonian Institution to continue his experiments. Under this grant the Smithsonian published his report of his theory and early experiments, Method of Reaching Extreme Altitudes. In 1918 he had successfully developed a solid-fuel ballistic rocket in which, however, even the United States Army lost interest after the Armistice. Convinced that rockets would eventually permit travel into outer space, Goddard after the war had continued his research at Clark University, seeking to develop vehicles that could penetrate into the ionosphere. In contrast to Tsiolkovskiy and Oberth, he set himself to devising practical means of attaining the goal they all three aspired to. In 1926 he successfully launched a rocket propelled by gasoline and liquid oxygen, a "first" that ranks in fame with the Wright brothers' Kitty Hawk flights of 1903. With the help of Charles Lindbergh after his dramatic solo transatlantic flight, Goddard obtained a grant of $50,000 from Daniel Guggenheim and equipped a small laboratory in New Mexico where he built several rockets. In 1937, assisted by grants from the Daniel and Florence Guggenheim Foundation, he launched a rocket that reached an altitude of 9,000 feet. Although not many people in the United States knew much about his work, a few had followed it as closely as his secretiveness allowed them to; among them were members of the American Interplanetary Space Society, organized in 1930 and later renamed the American Rocket Society. With the coming of World War II Goddard abandoned his field experiments, but the Navy employed him to help in developing liquid propellants for JATO, that is, jet-assisted takeoff for aircraft. When the Nazi "buzz" bombs of 1943 and the supersonic "Vengeance" missiles—the "V-2s" that rained on London during 1944 and early 1945—awakened the entire world to the potentialities of rockets as weapons, a good many physicists and military men studied his findings with attention. By a twist of fate, Goddard, who was even more interested in astronautics than in weaponry, died in 1945, fourteen years before most of his countrymen acknowledged manned space exploration as feasible and recognized his basic contribution to it by naming the government's new multi-million-dollar experimental station at Beltsville, Maryland, "The Goddard Space Flight Center."
During 1943 and early 1944, Commander Harvey Hall, Lloyd Berkner, and several other scientists in Navy service examined the chances of the Nazis' making such advances in rocketry that they could put earth satellites into orbit either for reconnaissance or for relaying what scare pieces in the press called "death rays." While the investigators foresaw well before the first V—2 struck Britain that German experts could build rockets capable of reaching targets a few hundred miles distant, study showed that the state of the art was not yet at a stage to overcome the engineering difficulties of firing a rocket to a sufficient altitude to launch a body into the ionosphere, the region between 50 and 250 miles above the earth's surface. In the process of arriving at that conclusion members of the intelligence team, like Tsiolkovskiy and Oberth before them, worked out the mathematical formulas of the velocities needed. Once technology had progressed further, these men knew, an artificial earth-circling satellite would be entirely feasible. More important, if it were equipped with a transmitter and recording devices, it would provide an invaluable means of obtaining information about outer space.
At the end of the war, when most Americans wanted to forget about rockets and everything military, these men were eager to pursue rocket development in order to further scientific research. In 1888 Simon Newcomb, the most eminent American astronomer of his day, had declared: "We are probably nearing the limit of all we can know about astronomy." In 1945, despite powerful new telescopes and notable advances in radio techniques, that pronouncement appeared still true unless observations made above the earth's atmosphere were to become possible. Only a mighty rocket could reach beyond the blanket of the earth's atmosphere; and in the United States only the armed services possessed the means of procuring rockets with sufficient thrust to attain the necessary altitude. At the same time a number of officers wanted to experiment with improving rockets as weapons. Each group followed a somewhat different course during the next few years, but each gave some thought to launching an "earth-circling spaceship," since, irrespective of ultimate purpose, the requirements for launching and flight control were similar. The character of those tentative early plans bears examination, if only because of the consequences of their rejection.
"Operation Paperclip," the first official Army project aimed at acquiring German know-how about rocketry and technology, grew out of the capture of a hundred of the notorious V— 2s and out of interrogations of key scientists and engineers who had worked at the Nazi's rocket research and development base at Peenemuende. Hence the decision to bring to the United States about one hundred twenty of the German experts along with the captured missiles and spare parts. Before the arrival of the Germans, General Donald Putt of the Army Air Forces outlined to officers at Wright Field some of the Nazi schemes for putting space platforms into the ionosphere; when his listeners laughed at what appeared to be a tall tale, he assured them that these were far from silly vaporings and were likely to materialize before the end of the century. Still the haughtiness of the Germans who landed at Wright Field in the autumn of 1945 was not endearing to the Americans who had to work with them. The Navy wanted none of them, whatever their skills. During a searching interrogation before the group left Germany a former German general had remarked testily that had Hitler not been so pig-headed the Nazi team might now be giving orders to American engineers; to which the American scientist conducting the questioning growled in reply that Americans would never have permitted a Hitler to rise to power.
At the Army Ordnance Proving Ground at White Sands in the desert country of southern New Mexico, German technicians, however, worked along with American officers and field crews in putting reassembled V-2s to use for research. As replacing the explosive in the warhead with scientific instruments and ballast would permit observing and recording data on the upper atmosphere, the Army invited other government agencies and universities to share in making high-altitude measurements by this means. Assisted by the German rocketeers headed by Wernher von Braun, the General Electric Company under a contract with the Army took charge of the launchings. Scientists from the five participating universities and from laboratories of the armed services designed and built the instruments placed in the rockets' noses. In the course of the next five years teams from each of the three military services and the universities assembled information from successful launchings of forty instrumented V—2s. In June 1946 a V—2, the first probe using instruments devised by members of the newly organized Rocket Sonde Research Section of the Naval Research Laboratory, carried to an altitude of sixty-seven miles a Geiger-counter telescope to detect cosmic rays, pressure and temperature gauges, a spectrograph, and radio transmitters. During January and February 1946 NRL scientists had investigated the possibility of launching an instrumented earth satellite in this fashion, only to conclude reluctantly that engineering techniques were still too unsophisticated to make it practical; for the time being, the Laboratory would gain more by perfecting instruments to be emplaced in and recovered from V-2s. As successive shots set higher altitude records, new spectroscopic equipment developed by the Micron Waves Branch of the Laboratory's Optics Division produced a number of excellent ultraviolet and x-ray spectra, measured night air glow, and determined ozone concentration. In the interim the Army's "Bumper" project produced and successfully flew a two-stage rocket consisting of a "WAC Corporal" missile superimposed on a V—2.
After each launching, an unofficial volunteer panel of scientists and technicians, soon known as the Upper Atmosphere Rocket Research Panel, discussed the findings. Indeed the panel coordinated and guided the research that built up a considerable body of data on the nature of the upper atmosphere. Nevertheless, because the supply of V—2s would not last indefinitely, and because a rocket built expressly for research would have distinct advantages, the NRL staff early decided to draw up specifications for a new sounding rocket. Although the Applied Physics Laboratory of the Johns Hopkins University, under contract with the Navy's Bureau of Ordnance and the Office of Naval Research, was modifying the "WAC Corporal" to develop the fin-stabilized Aerobee research rocket, NRL wanted a model with a sensitive steering mechanism and gyroscopic controls. In August 1946 the Glenn L. Martin Company won the contract to design and construct a vehicle that would meet the NRL requirements.
Four months before the Army Ordnance department started work on captured V—2s, the Navy Bureau of Aeronautics had initiated a more ambitious research scheme with the appointment of a Committee for Evaluating the Feasibility of Space Rocketry.
Unmistakably inspired by the ideas of members of the Navy intelligence team which had investigated Nazi capabilities in rocketry during the war, and, like that earlier group, directed by the brilliant Harvey Hall, the committee embarked upon an intensive study of the physical requirements and the technical resources available for launching a vessel into orbit about the earth. By 22 October 1945, the committee had drafted recommendations urging the Bureau of Aeronautics to sponsor an experimental program to devise an earth- orbiting "space ship" launched by a single-stage rocket, propelled by liquid hydrogen and liquid oxygen, and carrying electronic equipment that could collect and transmit back to earth scientific information about the upper atmosphere. Here was a revolutionary proposal. If based on the speculative thinking of Navy scientists in 1944, it was now fortified by careful computations. Designed solely for research, the unmanned instrumented satellite weighing about two thousand pounds and put into orbit by a rocket motor burning a new type of fuel should be able to stay aloft for days instead of the seconds possible with vertical probing rockets. Nazi experts at Peenemuende, for all their sophisticated ideas about future space flights, had never thought of building anything comparable.
The recommendations to the Bureau of Aeronautics quickly led to exploratory contracts with the Jet Propulsion Laboratory of the California Institute of Technology and the Aerojet General Corporation, a California firm with wartime experience in producing rocket fuels.
Cal Tech's report, prepared by Homer J. Stewart and several associates and submitted in December 1945, verified the committee's calculations on the interrelationships of the orbit, the rocket's motor and fuel performance, the vehicle's structural characteristics, and payload. Aerojet's confirmation of the committee computations of the power obtainable from liquid hydrogen and liquid oxygen soon followed. Thus encouraged, BuAer assigned contracts to North American Aviation, Incorporated, and the Glenn L. Martin Company for preliminary structural design of the "ESV," the earth satellite vehicle, and undertook study of solar-powered devices to recharge the satellite's batteries and so lengthen their life. But as estimates put the cost of carrying the program beyond the preliminary stages at well over $5 million, a sum unlikely to be approved by the Navy high brass, ESV proponents sought Army Air Forces collaboration. Curiously enough, with the compartmentation often characteristic of the armed services, BuAer apparently did not attempt to link its plans to those of the Naval Research Laboratory.
In March 1946, shortly after NRL scientists had decided that a satellite was too difficult a project to attempt as yet, representatives of BuAer and the Army Air Forces agreed that "the general advantages to be derived from pursuing the satellite development appear to be sufficient to justify a major program, in spite of the fact that the obvious military, or purely naval applications in themselves, may not appear at this time to warrant the expenditure." General Curtis E. LeMay of the Air Staff did not concur. Certainly he was unwilling to endorse a joint Navy-Army program. On the contrary, Commander Hall noted that the general was resentful of Navy invasion into a field "which so obviously, he maintained, was the province of the AAF." Instead, in May 1946, the Army Air Forces presented its own proposition in the form of a feasibility study by Project Rand, a unit of the Douglas Aircraft Company and a forerunner of the RAND Corporation of California. Like the scientists of the Bureau of Aeronautics committee, Project Rand mathematicians Project Rand mathematicians and engineers declared technology already equal to the task of launching a spaceship. The ship could be circling the earth, they averred, within five years, namely by mid-1951. They admitted that it could not be used as a carrier for an atomic bomb and would have no direct function as a weapon, but they stressed the advantages that would nevertheless accrue from putting an artificial satellite into orbit: "To visualize the impact on the world, one can imagine the consternation and admiration that would be felt here if the United States were to discover suddenly that some other nation had already put up a successful satellite."
Excerpted from Project Vanguard by Constance Mclaughlin Green, Milton Lomask. Copyright © 2009 Dover Publications, Inc.. Excerpted by permission of Dover Publications, Inc..
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