|astronautix.com||NASA long-range planning|
A Planning Coordination Steering Group at NASA Hq. received program options from working groups established to coordinate long-range planning in life sciences, earth-oriented applications, astronomy, lunar exploration, and planetary exploration. The Steering Group recommended serious consideration be given a four-phase exploration program using unmanned Lunar Orbiters, Surveyors, and manned lunar surface exploration.
The first phase, consisting of Ranger, Surveyor, Orbiter, and the initial Apollo landing was under way. The second phase would match the Apollo Applications program and would extend surface sampling and geologic mapping beyond the walking capability of a suited astronaut. The group recommended this phase launch one 14-day two-man mission per year beginning in 1970, with one or two Surveyors, and one unmanned Orbiter per year. The third phase would consist of one three-man 90-day mission per year. The final phase would consist of semipermanent manned stations. References: 16 .