S90-27205 (13 Sept. 1961) --- The unmanned Mercury-Atlas (MA-4) capsule sits atop its Atlas launch vehicle. The successful orbital flight followed the MA-3 mission, which was aborted earlier this year. Photo credit: NASA

Astronaut Walter M. "Wally" Schirra, one of the original seven astronauts for Mercury Project selected by NASA on April 27, 1959. The MA-8 (Mercury-Atlas) mission with Sigma 7 spacecraft was the third marned orbital flight by the United States, and made the six orbits in 9-1/4 hours.