John Watts Young is a retired American astronaut

Astronaut

An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft....

, test pilot, naval officer, and aeronautical engineer who became the ninth person to walk on the Moon

Moon

The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...

 as commander of the Apollo 16

Apollo 16

Young and Duke served as the backup crew for Apollo 13; Mattingly was slated to be the Apollo 13 command module pilot until being pulled from the mission due to his exposure to rubella through Duke.-Backup crew:...

 mission in 1972.

Young enjoyed the longest career of any astronaut, making six spaceflights over the course of 42 years of active NASA

NASA

The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 service. the first person to do so; and is the only person to have piloted four different classes of spacecraft: Gemini

Project Gemini

Project Gemini was the second human spaceflight program of NASA, the civilian space agency of the United States government. Project Gemini was conducted between projects Mercury and Apollo, with ten manned flights occurring in 1965 and 1966....

, the Apollo Command/Service Module

Apollo Command/Service Module

The Command/Service Module was one of two spacecraft, along with the Lunar Module, used for the United States Apollo program which landed astronauts on the Moon. It was built for NASA by North American Aviation...

, the Apollo Lunar Module

Apollo Lunar Module

The Apollo Lunar Module was the lander portion of the Apollo spacecraft built for the US Apollo program by Grumman to carry a crew of two from lunar orbit to the surface and back...

, and the Space Shuttle

Space Shuttle

The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...

.

In 1965, Young flew on the first manned Gemini mission

Gemini 3

Gemini 3 was the first manned mission in NASA's Gemini program, the second American manned space program. On March 23, 1965, the spacecraft, nicknamed The Molly Brown, performed the seventh manned US spaceflight, and the 17th manned spaceflight overall...

; and in 1969, was the first person to orbit the moon alone during Apollo 10

Apollo 10

Apollo 10 was the fourth manned mission in the American Apollo space program. It was an F type mission—its purpose was to be a "dry run" for the Apollo 11 mission, testing all of the procedures and components of a Moon landing without actually landing on the Moon itself. The mission included the...

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