As part of the race to the moon launched by President Kennedy, the Americans initiated a series of manned spaceflights. The two-man Gemini spacecraft served as a bridge between the single-seat Mercury capsule and Apollo rockets. The aim of the Gemini programme was to test techniques which could be used on a mission to the Moon (space walks and repairs, sustained flights, docking vessels in orbit). On 15 December 1965, Gemini 6 joined Gemini 7 in space and the two craft remained adjacent for 20 minutes. Physical docking with a rocket took place 4 months later.