CAPE CANAVERAL, Fla. - Mercury astronaut Scott Carpenter and his wife, Patricia, pose during a luncheon Feb. 17, 2012, celebrating 50 years of Americans in orbit, an era which began with John Glenn's Mercury mission MA-6, on Feb. 20, 1962. Glenn's launch aboard an Atlas rocket took with it the hopes of an entire nation and ushered in a new era of space travel that eventually led to Americans walking on the moon by the end of the 1960s. Glenn soon was followed into orbit by Carpenter, Walter Schirra and Gordon Cooper. Their fellow Mercury astronauts Alan Shepard and Virgil "Gus" Grissom flew earlier suborbital flights. Deke Slayton, a member of NASA's original Mercury 7 astronauts, was grounded by a medical condition until the Apollo-Soyuz Test Project in 1975. Photo credit: NASA/Kim Shiflett KSC-2012-1430