Apollo 16 was the tenth manned space flight in NASA's Apollo program. It was a J-Type mission with a longer stay on the Moon. Launched on April 16, 1972, Ken Mattingly stayed in orbit around the Moon in the Apollo Command Module, Casper. He spent 3 days, 9 hours and 28 minutes by himself, the longest solo US space flight.:77 On the Moon, astronauts John Young and Charles Duke got to put the Lunar Roving Vehicle through a series of tests, including s-turns, hairpin turns and quick stops. John W. Young was the commander of the mission.
A satellite was launched on the return journey to examine the Moon's mass and gravity, space particles near the Moon, and the interaction of magnetic fields between the Moon and Earth. The mission was stopped one day early as there were several problems with the spacecraft.