What NASA human spaceflight program preceded Project Apollo?
Answer
Project Gemini
Project Gemini followed Project Mercury and immediately preceded the Apollo program. Gemini, which translates to 'twins,' was specifically designed to bridge the technological and operational gap between the single-astronaut Mercury flights and the complex multi-person missions required for landing on the Moon under Apollo. It featured dual-pilot crews, reflecting its name perfectly, and served as the necessary intermediate step before the monumental effort of the Moon landing program could be formalized and executed.

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