Beyond the Atmosphere: Early Years of Space Science

[172] Among the most important contributions rockets, satellites, and space probes made to science was the new perspective they afforded in many areas, particularly in the earth and planetary sciences. Earth scientists, of course, had always enjoyed an advantage in being close to the object of study, living on the earth and immersed in its atmosphere, where the investigator could collect great quantities of data in situ. This was the very advantage that scientists seized upon when sounding rockets made it possible at long last to get on-the-spot measurements in the upper atmosphere. But a certain myopia was also associated with being too close to the object of study.
One of the tasks facing the researcher on the ground was developing an integrated picture of what was often a very large-scale, as well as complex, system. The meteorologist, for example, in spite of the enormous quantities of data he gathered on the weather, still found them too sparse. Even on land they came from rather widely separated stations, and there were none at all from vast stretches of the oceans. As a consequence the investigator was hard pressed to describe with any confidence the huge cyclonic systems and their interrelationship that characterized the general circulations of the earth's lower atmosphere let alone tell what the weather was like in remote unobserved regions. But when the first weather satellite pictures became available, showing cloud patterns over both continents and oceans, the meteorologist had at hand one of the integrating factors that he needed. For, clouds, being intimately associated with pressure patterns and air circulations, showed by their distributions the major weather systems. Most of what was seen in the early cloud pictures was expected, but there were also surprises. The author can recall hearing Dr. Harry Wexler, director of research for the U.S. Weather Bureau and strong proponent of weather satellites years before any satellite had flown, exclaim that he had never expected the large-scale patterns of atmospheric vortices that stood out in many satellite photographs. When in the course of time satellite [173] cloud imaging was improved in resolution and supplemented by techniques for measuring cloud heights, the vertical distribution of atmospheric temperatures, and local winds, meteorology became not merely local, not merely regional, but the global science it had always aspired-and needed-to be.1
Meteorologists were among the most ready to take advantage of the new approach and in short order used the satellite pictures in making weather forecasts. But such pictures also showed complete ice fields, total watersheds, entire geological provinces such as volcanic fields or geosyncline basins, varying patterns of land use, and vast expanses of ocean. To many it was clear from the start that the perspective afforded by satellite observations would in time prove of immense value in these and other areas. Such has proved true.2
After more than a decade of rocket sounding of the upper atmosphere, space science was quite ready to benefit from the new perspective. In the first half dozen years following the formation of NASA, especially rapid progress was made in the continued study of the upper atmosphere and ionosphere, solar physics, rocket astronomy, geodesy, and the magnetosphere. Accomplishments in the last two areas provide good illustrations of the power of space techniques for scientific research and are the subject of this chapter. The contributions to geodesy were anticipated, causing a number of researchers to give serious attention to the possibilities during the 1950s, years before Sputnik went aloft.3 In contrast, the magnetosphere emerged as something of a surprise from the early rocket and satellite work on particles and fields.