Moon by the Soviet Union's Luna 2, an unmanned spacecraft. The United States' NASA Apollo program achieved the only manned lunar missions to date, beginning with the first manned orbital mission by Apollo 8 in 1968, and six manned landings between 1969 and 1972, with the first being Apollo 11. These missions returned lunar rocks which have been used to develop a geological understanding of the Moon's origin, internal structure, and the Moon's later history. Since the Apollo 17 mission in 1972, the Moon has been visited only by unmanned spacecraft. Both the Moon's natural prominence in the earthly sky and
Voyage (novel) part of his fateful decision to decide the future of manned spaceflight, instead of deciding on the Space Shuttle program as he did in our timeline. Preparations for this new goal include slashing the number of moon landings so funding and leftover Apollo spacecraft hardware can go towards the efforts of the manned Mars mission. Apollo 12 still lands, Apollo 13 still suffers its disaster, but Apollo 14 is crewed by the astronauts of the cancelled Apollo 15 mission to carry out the scientific experiments on the lunar surface, and is the last manned moon landing. At the same time,