1930-

American astronaut who was the first astronaut to complete six flights. Young piloted the 1965 Gemini 3 flight and commanded Gemini 10 the next year. In 1969 Young was the command module pilot for Apollo 10. He landed on the moon in 1972 as commander of Apollo 16. Young flew on the space shuttle's 1981 inaugural flight and commanded the 1983 shuttle mission that first carried Spacelab experiments. Because he questioned safety procedures concerning the Challenger disaster, Young was replaced as chief of the astronaut office.