Apollo 8 carried the first humans to see the far side of the Moon.
Before Apollo 8, every human spaceflight had remained in Earth orbit. Apollo 8 launched in December 1968 and entered lunar orbit on December 24, allowing Frank Borman, James Lovell, and William Anders to observe terrain that is permanently hidden from Earth.
The far side is often incorrectly called the “dark side,” but it receives sunlight just like the near side. It is simply the hemisphere that faces away from Earth because the Moon is tidally locked to our planet. Apollo 8’s crew photographed and described its rugged craters during their ten lunar orbits.
The mission did not land. Its success provided vital confidence for later lunar landing attempts and helped confirm the performance of the Saturn V and Apollo spacecraft in deep space.