In 1952, a group of American scientists decided the world scientific community should undertake a third International Polar Year (IPY), building on those carried out in 1882–1883 and 1932–1933. The idea of launching an artificial scientific satellite during the IPY took hold and the event was renamed the International Geophysical Year, or IGY. It took place from 1957–1958. The IGY’s Earth satellite program led to the Soviet “Sputnik surprise” and the space race. It also led to the transformation of JPL from an Army weapons laboratory to NASA’s planetary exploration center. These events revolutionized American science, creating the new field of planetary science while enabling new discoveries in areas as diverse as geophysics and climate science.