Book excerpt: The launch of Sputnik in 1957 not only began the space age, it also showed that Soviet rockets were more powerful than American ones. Within months, the US Air Force hired Rocketdyne for a feasibility study of an engine capable of delivering at least 1 million pounds of thrust. Later, NASA ran the development of this F-1 engine in order to use it to power the first stage of the Saturn V rocket that would send Apollo missions to the Moon. It is no exaggeration to say that without the F-1 engine NASA would not have been able to achieve President Kennedy’s 1961 challenge to his nation to land a man on the Moon before the decade was out.