The Mars Excursion Module (MEM) was a spacecraft proposed by NASA in the 1960s for use in a manned mission to Mars. It formed part of Mars orbit rendezvous (MOR) and flyby-rendezvous mission profiles studied at NASA's Manned Spacecraft Center in the 1960s. The Mars Excursion Module would have been a combination of a Mars lander, short-stay surface habitat, and ascent vehicle; the ascent stage performed the rendezvous. The MEM would have been used for a 40-day stay on the Martian surface in the flyby-rendezvous mission profile or for a 10- to 40-day stay in the MOR profiles.