Apollo 15 15 separated from the booster, the S-IVB maneuvered away, and would impact the Moon about an hour after the crewed spacecraft entered lunar orbit, though due to an error the impact was away from the intended target. The booster's impact was detected by the seismometers left on the Moon by Apollo 12 and Apollo 14, providing useful scientific data. There was a malfunctioning light on the craft's service propulsion system (SPS); after considerable troubleshooting, the astronauts did a test burn of the system that also served as a midcourse correction. This occurred about 028:40:00 into the mission. Fearing that the
Apollo 8 Apollo 8 Apollo 8, the second manned spaceflight mission in the United States Apollo space program, was launched on December 21, 1968, and became the first manned spacecraft to leave low Earth orbit, reach the Moon, orbit it, and safely return. The three-astronaut crew—Frank Borman, James Lovell, and William Anders—became the first humans to travel beyond low Earth orbit, see Earth as a whole planet, and enter the gravity well of another celestial body. They were also the first humans to orbit another celestial body, see the far side of the Moon, witness and photograph an "Earthrise", escape the gravity