U.S. Proposals - 1950s and 1960s

In 1962, Aeronutronic Ford,^[14] General Dynamics and the Lockheed Missiles and Space Company made studies of Mars mission designs as part of NASA Marshall Spaceflight Center "Project EMPIRE".^[8] These studies indicated that a Mars mission (possibly including a Venus fly-by) could be done with a launch of eight Saturn V boosters and assembly in low Earth orbit, or possibly with a single launch of a hypothetical "post Saturn" heavy-lift vehicle. Although the EMPIRE missions were only studies, and never proposed as funded projects, these were the first detailed analyses of what it would take to accomplish a human voyage to Mars using data from the actual NASA spaceflight, and laid much of the basis for future studies, including significant mission studies by TRW, North American, Philco, Lockheed, Douglas, and General Dynamics, along with several in-house NASA studies.^[8]

Following the success of the Apollo Program, von Braun advocated a manned mission to Mars as a focus for NASAs manned space program.^[15] Von Braun's proposal used Saturn V boosters to launch nuclear-powered (NERVA) upper stages that would power two six-crew spacecraft on a dual mission in the early 1980s. The proposal was considered by (then president) Richard Nixon but passed over in favor of the Space Shuttle.