what is apollo 9?
It was a human spaceflight, the third in NASA's Apollo program.
Apollo 9
Apollo 9 was a March 1969 human spaceflight, the third in NASA's Apollo program.
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Apollo 9 [SEP] Introduction
Apollo 9 was a March 1969 human spaceflight, the third in NASA's Apollo program. Flown in low Earth orbit, it was the second crewed Apollo mission that the United States launched via a Saturn V rocket, and was the first flight of the full Apollo spacecraft: the command and service module (CSM) with the Lunar Module (LM). The mission was flown to qualify the LM for lunar orbit operations in preparation for the first Moon landing by demonstrating its descent and ascent propulsion systems, showing that its crew could fly it independently, then rendezvous and dock with the CSM again, as would be required for the first crewed lunar landing.