For the summer of 1960 committee members prepared a series of papers reporting on progress in the planetary and interplanetary sciences for publication in the Transactions of the American Geophysical Union. The President's Page in the Transactions for September 1960 carried a note from the author pointing out the importance of space science to geophysics and calling attention to the existence of the Planning Committee on Planetary Sciences. 44 Within the union there was a steady movement toward the creation of a new section on the planetary sciences. But space science was itself but an extension of the traditional disciplines, and there was opposition to the proposed action. The argument was that the existing sections of AGU could provide the desired home for the new activities in space. The section on meteorology, for example, could accommodate satellite meteorology. Any section dealing with an aspect of the earth sciences could house that same aspect of the planetary sciences. In fact, some feared that a separate section on the planetary sciences would become another little union within the overall union. Even members thoroughly involved in the space sciences-like John Simpson, experimenter on Pioneer and Explorer satellites, theoretical physicist Alexander Dessler, and Harry Wexler, director of research for the U.S. Weather Bureau-were opposed. Nevertheless, the strong coherence in the space sciences, generated by the peculiarities and demands of the space tools, sparked the push for a new section. The spring of 1961 saw a great deal of discussion of the matter, and at its 22 April 1961 meeting the council of the union approved in principle the formation of a new section-by a margin of one vote! The council asked that the entire organizational structure, activity, and nomenclature of the union be reviewed as a precaution against intolerable dislocations within the society. from addition of the new section. The review concluded that no other changes were required, and on 25 April 1962 the council gave final approval for the formation of a section on planetary sciences (which later in the decade divided into several groups). The author became the first president of the section, and Jastrow its first secretary, thus symbolizing the close relations that NASA had developed with the American Geophysical Union. The examples given here are only illustrative. The breadth of the space sciences generated an important association with many scientific and technical societies and institutes. The interest of the American Rocket Society and the Institute of Aeronautical Sciences-which soon merged into the new American Institute of Aeronautics and Astronautics-was an obvious one, as was that of the American Astronautical Society and the International Astronautical Federation, although their concern tended more toward the engineering and technology side of the picture. More directly concerned with space science were the Optical Society of America, the International Astronomical Union, the American Meteorological Society, the Geological Society of America, the American Institute of Biological Sciences, and a long list of others. For some of these, interest in space science flared up at the very start, while for others the interest gradually emerged as the program unfolded. Inheriting so much from the International Geophysical Year, NASA had an international program from the outset. 45 There were two main arenas, that of the international scientific circles such as the International Council of Scientific Unions and its newly formed Committee on Space Research, and that of a political nature, falling generally in the sphere of the United Nations. There were numerous political considerations relative to space, and NASA was immediately drawn into United Nations deliberations on space matters. But the natural arena for space science was the international scientific community, and from the start NASA gave strong support to the Committee on Space Research. Among the unions of the council represented on COSPAR were the International Union of Scientific Radio and the International Union of Geodesy and Geophysics, which had first recommended the use of scientific satellites during the International Geophysical Year. Following the organizing meeting convened by the author in London in November of 1958, COSPAR held its first full-scale business session in The Hague, 12-14 March 1959.46 At that meeting Richard Porter of the Space Science Board, U.S. representative to COSPAR, asked the author whether the United States might offer to launch space science experiments for COSPAR members. In a phone call to Washington, the author obtained Hugh Dryden's approval to inform the meeting that NASA would be willing to do so. Porter then wrote to President H. C. van de Hulst, saying that the United States would accept single experiments as part of larger payloads, or would launch complete payloads prepared by other countries.47 The response to the U.S. invitation was immediate, and before the year was out a number of cooperative projects had begun. With the Soviet Union, genuine cooperation proved to be difficult during the 1960s, less difficult in the 1970s climate of detente. These subjects are discussed at length in chapter 18. As the leaders of NASA worked to reshape the NACA into an aeronautics and space organization, they also laid the foundation for the many relationships with other government agencies, industry, and the scientific community that played an essential role in planning and conducting the program. But none of this would have been of any avail without the principal tools, the rockets and spacecraft essential to the investigation and exploration of space. A first order of business was to provide for these tools. That NASA set about to do, striving to overcome as soon as possible the visible gap that lay between the United States and the Soviet Union in propulsion capabilities and launchable spacecraft weights. Because of the central importance of launch vehicles and their payloads, the next chapter is devoted entirely to them. 10 Rockets and Spacecraft: Sine Qua Non Even as NASA was being formed, the stable of American sounding rockets was impressive. There were small (Deacon, Cajun, Arcon, Arcas), medium (Aerobee, Aerobee-Hi), and large (Viking) rockets. Viking had been designed to replace the V-2, which was no longer used after the test program ended in 1952. There were rockets using solid propellants (Deacon, Cajun, Arcon, Arcas) and rockets using liquid propellants (second stage of Aerobee, Viking). Multistage combinations (Nike-Deacon, NikeCajun, Aerobee) achieved higher altitudes than could economically be attained with single-stage rockets. Rockets had been launched from balloons, from aircraft, and from launchers aboard ships at sea. These sounding rockets and the high-altitude research program that went with them provided NASA with an immediately on-going component of its space science program.1 A similar situation existed with respect to the larger vehicles needed for launching spacecraft into orbit. The reentry test vehicle Jupiter C—which launched America's first satellite, Explorer 1, and which used the Redstone missile as its first stage-gave rise to a first group of what were called Juno space launch vehicles. Later versions of Juno used the more powerful Jupiter intermediate-range ballistic missile as the first stage.2 The Redstone, which was created for the Army by the von Braun team and in which one could detect a distinct V-2 ancestry, was on hand and was used for America's first suborbital manned flights.3 The Vanguard IGY launch vehicle, which used derivatives of the Viking and Aerobee sounding rockets as its first and second stages, was also available.4 NASA took over Vanguard from the Naval Research Laboratory and completed the program, after which the Vanguard first stage was retired; but the upper stages were combined with the Air Force's Thor to create the Thor-Delta, or simply Delta, launch vehicle, which from the very start was one of the most useful of the medium-sized combinations.5 In 1958 the Air Force's Atlas was the most powerful U.S. rocket that could be quickly pressed into service as a space launcher. To it was assigned the launching of the first American astronauts to go into orbit. Atlas eventually became the main stage of Atlas-Agena and Atlas-Centaur, multistage launch vehicles used to put multiton payloads into space. The imposing presence of the Soviet Union in space following the launching of the first Sputniks and the substantial lead it apparently had over the U.S. in payload capability generated a sense of urgency to develop very large payload capabilities. But with the variety of vehicles already in its stable or imminent, the United States clearly was not going to have to start from scratch. Indeed, had the country been willing to use the von Braun rockets for the IGY satellite program, the first satellite in orbit could well have borne a "made in America" stamp. At any rate, even this partial survey of the situation at the time NASA got going shows how deep in the rocket and missile work of the 1950s lay some of the roots of the subsequent space program. Of course, along with the missiles and rockets available to NASA and the military were associated facilities and equipment already in operation. Launch ranges existed in Florida, California, New Mexico, and Canada. Tracking and telemetering stations, strategically located in the U.S. and elsewhere, were working. Vanguard Minitrack network of radio-tracking and telemetering stations for operating with the IGY satellites spanned the globe and provided a nucleus on which to build for an enlarged program of the future. IGY optical tracking stations also girdled the globe and were immediately available for photographic and visual tracking of spacecraft that were large enough to be detected by such means. To produce all these a substantial component of American aerospace, electronics, and other industry had been employed, generating hardware and acquiring an experience ready to be used for tackling the challenges that lay ahead.7 One of the first tasks facing NASA in the fall of 1958 was to determine what additional launch vehicles would be required to accomplish the space missions planned for the program. While most of the launchers would derive from military hardware, some, especially for the manned spaceflight program, would have to be built from scratch. So, too, would the spacecraft for the science, applications, and manned spaceflight missions. LAUNCH VEHICLES It is not necessary for understanding the relationship of launch vehicles to the space science program to delve deeply into how they were developed, but a few principles should be understood. First, a number of different vehicles were required. One might have supposed that a single launch vehicle, which could do everything the program required, would be ideal. With only one manufacturing line, one kind of assembly, test, and launch facilities, one kind of operational equipment and procedures, and basically one launch team, a substantial background of experience would quickly build up for that vehicle. Engineers and technicians would become thoroughly familiar with its characteristics and idiosyncrasies, so that a high degree of reliability could be ensured. But in an era when a launch vehicle was expended for each firing, the economics would not be favorable. For, to be acceptable, a single vehicle would have to be able to accomplish both the simplest and the most difficult of the missions required—from small, near-earth satellite missions to manned flights to the moon. On the most difficult missions, the launch vehicle would presumably operate most efficiently, and the costs would be commensurate with the accomplishments. But to use such a vehicle for less demanding missions would be most inefficient; indeed, the cost of the launch vehicle could overwhelm the cost of the spacecraft. To mitigate this problem of cost there would, of course, be pressure to fly many small missions on a single launch vehicle, or to let small missions ride piggyback on larger ones, thus, reducing the cost per spacecraft; but then different kinds of complications would enter in. Some of these would be fundamental, as when one set of experiments required a circular orbit, another set an eccentric orbit, still another a polar orbit, and a fourth an equatorial orbit. For expendable launch vehicles such considerations led to the conclusion that the most efficient approach would be a graduated series running from a small, inexpensive vehicle to the very large, very expensive ones. The gradation between vehicles would be large enough to yield a substantial increase in payload and mission capability, but small enough to avoid having to use vehicles too costly for their assigned missions. Obviously the way in which these requirements were met was a matter of judgment, and in some respects arbitrary. The subject was constantly under study by both the military and NASA.8 Second, the basic physics of rockets dictated that major launch vehicles should be multistage, or step, rockets—that is, combinations of two or more rockets, called stages, which burn one after the other. As soon as the first stage has used its propellants, it is discarded, after which at an appropriate time the second stage is ignited. When the second stage has burned out and been discarded, the third stage is ready to fire. And so on. Multistaging is important for rockets that must work against the force of gravity, for otherwise the propellants must supply the energy needed to propel the entire rocket structure against the pull of gravity for the whole launching phase. But with staging, in which portions of the structure are discarded as soon as they are no longer needed, only a small fraction of the entire vehicle need be propelled into the final orbit or space trajectory. The early rocket pioneers recognized the importance of staging, a point that Robert Goddard elaborated in his famous Smithsonian paper.9 In the space program two-stage and three-stage vehicles became common, four- and five-stage combinations not uncommon. |