Canceled Apollo missions wasn't going to have a flight for him". Another lunar landing was lost in April 1970 when Apollo 13 had its in-flight failure, and the Fra Mauro landing site was reassigned to Apollo 14. Then on September 2, 1970, NASA announced it was canceling the H4 and J4 missions, due to more budget cuts. Skylab was also pushed out to 1973, and the final landing schedule became: At the time, 35 of NASA's 49 active astronauts were waiting for a chance for a mission. In the closing days of the program, Apollo 17 LMP Harrison Schmitt aggressively lobbied for a
Apollo program landing was prevented by an oxygen tank explosion in transit to the Moon, which destroyed the service module's capability to provide electrical power, crippling the CSM's propulsion and life support systems. The crew returned to Earth safely by using the lunar module as a "lifeboat" for these functions. Apollo used Saturn family rockets as launch vehicles, which were also used for an Apollo Applications Program, which consisted of Skylab, a space station that supported three manned missions in 1973–74, and the Apollo–Soyuz Test Project, a joint US-Soviet Union Earth-orbit mission in 1975. Apollo set several major human spaceflight milestones. It