CAPE CANAVERAL, Fla. - Lyle Holloway, former director of launch sites originally for McDonnell Douglas, helps NASA, the U.S. Air Force, United Launch Alliance, Boeing, Pratt and Whitney Rocketdyne, Aerojet and the NASA Alumni League celebrate the Delta expendable launch vehicle program's 50th anniversary at the Radisson Resort in Cape Canaveral, Fla., on May 16. NASA launched the first Delta rocket, which only was intended to be an interim launch vehicle, on May 13, 1960. A half-century later, more than 300 Delta rockets have launched to place crucial weather and environmental satellites into Earth orbit. The vehicles also have sent spacecraft on missions to other planets and comets, and to study the universe. Currently, the Delta II and Delta IV are in use by NASA's Launch Services Program based at Kennedy Space Center in Florida, and are launched by United Launch Alliance. Photo credit: NASA_Amanda Diller