Apollo Program - Spacecraft

Spacecraft

Preliminary design studies of Apollo spacecraft began in 1960 as a three-man command module supported by one of several service modules providing propulsion and electrical power, sized for use in various possible missions, such as: shuttle service to a space station, circumlunar flight, or return to Earth from a lunar landing. Once the Moon landing goal became official, detailed design began of the Command/Service Module (CSM), in which the crew would spend the entire direct-ascent mission and lift off from the lunar surface for the return trip. The final choice of lunar orbit rendezvous changed the CSM's role to a translunar ferry used to transport the crew and a new spacecraft, the Lunar Excursion Module (LEM, later shortened to Lunar Module, LM), which would take two men to the lunar surface and return them to the CSM.

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