Apollo 11 as CMP, and Haise as LMP. Anders had flown with Lovell on Apollo 8. In early 1969, he accepted a job with the National Aeronautics and Space Council effective August 1969, and announced that he would retire as an astronaut at that time. Ken Mattingly was moved from the support crew into parallel training with Anders as backup CMP in case Apollo 11 was delayed past its intended July launch date, at which point Anders would be unavailable. Lovell, Haise, and Mattingly were later assigned as the prime crew of Apollo 13. During Projects Mercury and Gemini, each mission had
Canceled Apollo missions to Apollo 17 under pressure from the scientific community, replacing Joe Engle. Schmitt, a geologist, became the only professional scientist and the twelfth man to walk on the Moon. Slayton's intention for the Apollo 19 crew was the original (prior to cancellation) Apollo 16 backup crew: For Apollo 20 there is even more uncertainty. Based on normal crew rotation, the crew would likely have been: Another possibility would have been: One of the surplus CSMs, CSM-119, was modified to carry two additional crew and kept on standby for a potential rescue mission in case of issues on-board Skylab. During Skylab