THE SPACE DEPARTMENT AFTER 40 YEARS: AN OVERVIEW APL’s Space Department After 40 Years: An Overview Stamatios M. Krimigis The APL Space Department came into being in 1959 to implement the APL- invented global satellite navigation concept for the Navy. The Transit System compiled unparalleled availability and reliability records. Space engineering “firsts” spawned by Transit have constituted standard designs for spacecraft systems ever since. By the mid- 1960s, missions were designed to perform geodesy investigations for NASA and, later, astronomy and radiation experiments. In the 1970s, space science missions began to transform the Department from an engineering to a science-oriented organization. The program for ballistic missile defense in the mid-1980s became the principal focus of the Department’s work with overlapping engineering and applied science activity, and lasted through the early 1990s. After the Cold War, science missions in both planetary and Sun–Earth connections plus experiments on NASA spacecraft shifted the projects from some 70% DoD to about 70% NASA. The unique blend of world-class science and instrumentation combined with innovative engineering represents a powerful combination that augurs well for the future of the Space Department. (Keywords: History, Space Department, Space science, Space technology.) EARLY HISTORY The Space Department was officially established by Geiger-Mueller counters, with the objective of measur- memorandum on 24 December 1959 as the Space ing various spectral lines and the intensity of primary Development Division, approximately 3 months after cosmic radiation as it was attenuated through the the failed launch of Transit 1A on 17 September 1959.1 Earth’s atmosphere.2 Van Allen’s group also obtained a Dr. Richard B. Kershner was appointed supervisor of number of detailed photographs of the visible and near- the division, with Theodore Wyatt as project engineer infrared surface of Earth and its cloud cover that for Transit. One could argue, however, that the intel- showed for the first time the curvature of the Earth. lectual seeds for the new division go back to 1946, when This high-altitude research was eventually incorporat- a small group of scientists at APL under the leadership ed into the APL Research Center, which had been of James A. Van Allen (of the Van Allen radiation established in 1947 by Lawrence Hafstad, then director belts) began instrumenting a number of captured Ger- of APL. The research continued with the development man V2 rockets with experiments that included cam- of the Aerobee rocket, which was transferred to indus- eras, visible and near-infrared spectrometers, and try and became the principal sounding rocket research JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 20, NUMBER 4 (1999) 467 S. M. KRIMIGIS tool for many groups in the United States until the Our predecessors, under the charismatic leadership program was terminated in 1985. After Van Allen’s of the first Space Department Head, Richard Kershner, departure in December 1950 to assume the leadership succeeded admirably in their task and in the process of the Department of Physics and Astronomy at the established the principal characteristics that have University of Iowa (more on this to follow), activity shaped the Department’s culture as we know it today. relating to space did not exist at the Laboratory until Their success is all the more impressive by today’s stan- the rude awakening of the entire country following the dards in that they were able to make the Transit System launch of Sputnik on 4 October 1957. operational 2 years ahead of schedule and within the The acquisition of Doppler data from Sputnik by originally allocated costs. They did so while establish- Guier and Weiffenbach3 and the subsequent formula- ing a host of technological “firsts” that have since been tion of the satellite navigation concept4 gave rise to the used routinely by the satellite industry as basic tools of Transit Program and made it necessary to establish a spaceflight design and implementation. A few of these division within which the engineering development include the first attitude control of a spacecraft using and implementation would take place. Thus came into permanent magnets, the first solar attitude detectors, being, 40 years ago, what we now call the Space De- the first satellite electronic memory, the first nuclear partment. These early activities are illustrated schemat- power in a spacecraft, hysteresis rods for dumping sat- ically in Fig. 1. ellite libration—and all of these before the end of 1961! The task undertaken by the new department was These were followed by gravity-gradient stabilization, nothing short of revolutionary. For the previous 4000 a magnetic spin/despin system, the first integrated cir- years the principal means for navigation on a global cuits used in space, etc.5 It is not my intent here to give scale was similar to that used by Odysseus on his return a detailed description of the excitement and enthusi- journey to his island of Ithaca by keeping the Great asm of our colleagues, who knew that they were making Bear to his left and his eyes fixed on the Pleiades. The history. They were a very talented bunch, and they promise of Transit was to do away with astronomical have described their experiences in several specialized observation as the principal means of worldwide nav- publications (see, e.g., Ref. 6 and the article by Bos- igation and replace it with an all-weather global sys- trom, this issue). Rather, my purpose is to point out that tem that would provide accurate locations at any Transit formed the foundation of our technology and point with precision unheard of for its time (less than management culture on which much of what we do 0.5 mile). today is based. 1942 1946–1949 1957 1958 1959 APL established Invention of NASA 17 September to develop proximity Doppler established APL launched fuze for the Navy V2 rocket research navigation from NACA first satellite B A APL space science and technology Service Space Technology Space to the science development environment nation research Figure 1. The evolution of space science and technology at APL: The pioneering years. 468 JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 20, NUMBER 4 (1999) THE SPACE DEPARTMENT AFTER 40 YEARS: AN OVERVIEW SEEDS OF THE SCIENCE ACTIVITY and also on the synthetic aperture radar, which were The Space Department, coming out of the Transit flown on that spacecraft in 1978. A detailed survey of program in the late 1960s, was a first-class engineering, the Earth’s magnetic field came next when the Magsat technical, and management organization, with some satellite, which used, for the first time, a set of micro- elements of science that were necessary for assessing the processors for the attitude and command systems, was space environment for an operational satellite system. flown in October 1979. The principal navigation problem having been solved, On another track, work related to radiation inves- Navy support began to decline significantly while in- tigations and astronomical research began to take shape terest by other agencies, principally NASA, with a in the Department. Initially, some particle instruments need for an experienced organization to implement were selected and flown on NASA spacecraft such as science and applications programs, started to increase. Interplanetary Monitoring Platform (IMP-4 and -5), Thus, while we continued to upgrade the accuracy of but eventually a larger-scale program was undertaken the navigation system and to improve the technology, for the Goddard Space Flight Center (GSFC) to design that level of effort was not sufficient to maintain and and implement the Small Astronomy Satellite series, improve the capabilities of the staff in engineering SAS-1, -2, and -3. The first of these flew in December development. 1970 and proved a resounding success by identifying a It was in the mid-1960s that work for NASA started, large of number of X-ray sources, the first such survey understandably in the area of geodesy. The Geodetic of the X-ray sky from space. Subsequent missions per- Earth Orbiting Satellites (GEOS-A and -B), launched formed the first gamma ray survey (SAS-2, 1972) and in 1965 and 1968, respectively, were the first NASA detailed investigation of the spectral characteristics of spacecraft to employ gravity gradient stabilization. X-ray sources (SAS-3, 1975). This period is shown They fulfilled all their science objectives, including schematically in Fig. 2. measurements of Earth’s gravity field to 5 parts in 108. These geodetic missions were followed by the launch of GEOS-C in 1975, the first full-fledged ocean radar SCIENCE’S COMING OF AGE altimeter mission, which operated for over 3 years and Through the 1970s a subtle transformation began to mapped the topography of the ocean surface to an take place in the mix of work taken up by the Space accuracy of 50 cm. GEOS-C was followed by the Lab- Science Branch in the Department. In the competition oratory’s work on the Seasat mission ocean altimeter for investigations for what was then called the Outer 1961 1963 1964 1967 1969 1970 1971 1972 1973 ␥ Space plasma UV astronomy X-ray, -ray astronomy Space currents research (5E-5) (SAS-1, SAS-2, SAS-3) (TRIAD) Injun 1 Ionospheric research (University of Iowa) (BE-B) Transit 4A Remote sensing (DODGE) Long-term monitoring of space environment (NASA) 5E-1 IMP-4 IMP-5 IMP-6 IMP-7 IMP-8 APL space science and technology Solar protons and Van Allen belts Multipurpose Unrestricted research applications data distribution Figure 2. The evolution of space science and technology at APL: The discovery years. JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 20, NUMBER 4 (1999) 469 S. M. KRIMIGIS Planets Grand Tour missions, we were selected in 1971 mission and was to be used by the Navy.