Buzz Aldrin while Command Module Pilot Michael Collins remained in lunar orbit. A Presbyterian elder, Aldrin became the first person to hold a religious ceremony on the Moon when he privately took communion. Upon leaving NASA in 1971, he became Commandant of the U.S. Air Force Test Pilot School. He retired from the Air Force in 1972, after 21 years of service. His autobiographies "Return to Earth," (1973) and "Magnificent Desolation" (2009), recount his struggles with clinical depression and alcoholism in the years after leaving NASA. He continued to advocate for space exploration, particularly a manned mission to Mars, and developed the
Buzz Aldrin Collins recovered he joined Armstrong's crew as CMP. In the meantime, Fred Haise filled in as backup LMP, and Aldrin as backup CMP for Apollo 8. An effect of this was that while the CMP usually occupied the center couch on takeoff, Aldrin occupied it rather than Collins, as he had already been trained in it before Collins arrived. Apollo 11 was the second all-veteran multi-person crew on an American mission, the first being that of Apollo 10. An all-veteran crew would not be flown again until STS-26 in 1988. Early versions of the EVA checklist had the Lunar Module