Kennedy Space Center Director and former astronaut Bob Cabana addresses the audience at a celebration at Complex 5/6.

Kennedy Space Center Director and former astronaut Bob Cabana addresses the audience at a celebration at Complex 5/6 on Cape Canaveral Air Force Station in Florida.

The celebration was held at the launch site of the first U.S. manned spaceflight May 5, 1961, to mark the 50th anniversary of the flight. Fifty years ago, astronaut Alan Shepard lifted off inside the Mercury capsule, "Freedom 7," atop an 82-foot-tall Mercury-Redstone rocket at 9:34 a.m. EST, sending him on a remarkably successful, 15-minute suborbital flight. The event was attended by more than 200 workers from the original Mercury program and included a re-creation of Shepard's flight and recovery, as well as a tribute to his contributions as a moonwalker on the Apollo 14 lunar mission. For more information, visit www.nasa.gov/topics/history/milestones/index.html. Photo credit: NASA/Kim Shiflett