On his first flight in space (1966), Aldrin piloted Gemini 12 with commander James Lovell. During a 5 1/2-hour space walk, Aldrin helped to solve the exhaustion problem that had plagued earlier spacewalkers by using straps on the spacecraft as handholds and by pacing his efforts. He was then assigned as lunar module pilot to what became the first lunar landing mission ( Apollo 11, July 16–24, 1969). His responsibilities included monitoring the lunar module systems while commander Neil Armstrong concentrated on landing. After Aldrin joined Armstrong on the Moon, they set up basic science experiments and collected samples of the Moon's surface.
Back on Earth, Aldrin, Armstrong, and command module pilot Michael Collins appeared before a joint session of Congress and made a global goodwill tour. In 1971, Aldrin left NASA to become commander of the Air Force Aerospace Research Pilots School. In 1972 he resigned from the force with the rank of colonel and entered private business. His autobiography, Return to Earth (1973), relates the pressures on the Apollo 11 crew and his subsequent nervous breakdown and recovery. Baptized Edwin E. Aldrin, he has since adopted his long-standing nickname as his first name.