Apollo 16 was a mission of the United States space program that sent three astronauts to the moon. It was the fifth time humans had visited the moon and it was the first time that a moon rover was used to explore the surface of the moon. The astronauts on the mission were John Young, Thomas Mattingly, and Charles Duke. They spent three days on the Moon, exploring and collecting samples of Moon rocks, which they brought back to Earth. The mission helped scientists learn more about the history of the moon and how it was formed.