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Wally Schirra and Eugene Cernan were two of the astronauts who died, leaving Stafford the last surviving crew member of their shared missions. Schirra died on June 3, 2007, at the age of 84. He was a member of the Mercury Seven, the first group of astronauts selected by NASA. Schirra flew on three space missions: Mercury-Atlas 8, Apollo 7, and Skylab 4.