Direct ascent

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Artist's conception early Apollo spacecraft that used direct ascent

Direct ascent was a proposed method for a mission to the Moon. In the United States, direct ascent proposed using the enormous Nova rocket or Saturn C-8 to loft a spacecraft directly to the Moon, where it would land tail-first and then launch off the Moon back to Earth. The other options that NASA considered for the mission to the moon were Lunar Orbit Rendezvous and Earth Orbit Rendezvous. Lunar Orbit Rendezvous was eventually chosen as the most feasible.

The Soviets also considered several direct ascent-strategies, though in the end they settled on an approach similar to NASA's: two men in a Soyuz spacecraft capsule and a one-man lander. The failure of the Soviets' N1 Rocket delayed their lunar program substantially, however, and they were nowhere close when Apollo 11 lifted off and made the first lunar landing.

Science fiction movies such as Destination Moon had frequently depicted direct ascent missions. In real life, however, it was discarded due to the sheer impossibility of landing a rocket the size of the Atlas tail-first on the Moon.