James Alton McDivitt (Brig Gen, USAF Ret.) (born June 10, 1929) is a former NASA astronaut and engineer who flew in the Gemini and Apollo programs. He commanded the Gemini 4 flight in which Edward H. White performed the first US space walk, and later the Apollo 9 flight which was the first manned Earth orbital test of the Apollo Lunar Module. He became Apollo Spacecraft Manager before resigning from NASA and retiring from the Air Force in 1972.