Taking the Measure of Planet Earth: From Kilometers to Millimeters in the First Half Century of the Space Age

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In October 1957, the USSR launched Sputnik 1, the first artificial satellite to orbit Earth. Having developed a rocket that could carry a satellite into orbit, it was only a matter of time before they would have intercontinental ballistic missiles that could deliver nuclear warheads to targets anywhere on the globe. The US moved to counter the perceived threat, launching a program to build hundreds of hardened missile sites, and submarines armed with missiles, that could respond within minutes to an attack on the US or its allies. President Eisenhower knew that much of the US military space program would necessarily be cloaked in secrecy, but he wanted the scientific exploration of space to be open to as many people, of all nationalities, as possible. In July 1958 he established the National Aeronautics and Space Administration . Eleven years later, in 1969, hundreds of millions of people around the world watched American astronauts walk on the surface of the Moon and return safely to Earth, on live television.
Both the military and scientific space programs required far more accurate measurements of the size, shape, orientation, and gravity field of Earth, as well as three dimensional coordinates of missile sites, tracking stations, and targets, than geodesists could extract from the centuries of ground-based observations they had on-hand. The solution? Satellite geodesy. Over the following decades dedicated geodetic satellites, some with military and others with scientific purposes, were launched into orbit, to be tracked by global networks of stellar cameras, Doppler receivers, radar, and laser ranging units.
When Bill Carter graduated from college and was commissioned a Second Lieutenant in the US Air Force, in 1961, his first assignment was to 1381st Geodetic Survey Squadron, in Orlando FL, as a geodetic officer. That was the start of a career now exceeding some 57 years, including eight years of active military service, 20 years as a research geodesist at the National Oceanic and Atmospheric Administration, and nearly three decades in academia, teaching geodetic science classes and doing cutting edge research funded by NASA, the National Science Foundation , and other federal, state, and local government agencies. In his memoirs, Bill takes readers inside the geodetic community and shares the sometimes exhilarating and sometimes frustrating process by which geodesists improved their measurements of Earth from kilometers to millimeters in the first half century of the space age.