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 test pilot training, which was a prerequisite at the time. On the completion of his doctorate, Aldrin was assigned to the Gemini Target Office of the Air Force Space Systems Division in Los Angeles, working with the Lockheed Aircraft Corporation on enhancing the maneuver capabilities of the Agena target vehicle which was to be used by NASA's Project Gemini. He was then posted to the Space Systems Division's field office at NASA's Manned Spacecraft Center in Houston, where he was involved in integrating Department of Defense experiments into Project Gemini flights. Aldrin's initial application to join the astronaut corps when