NASA scientist who led the Johnson Space Center in Houston and oversaw the Apollo moon landings.
He took a childhood interest in creating rubber band-launched toy airplanes to the University of Minnesota, where he studied aeronautical engineering.
He worked at National Advisory Committee for Aeronautics on free-flight rocket-powered experiments, and joined NASA when the agency formed in 1958.
He was married twice and had one daughter.
He and Buzz Aldrin were both inducted into the International Space Hall of Fame.