Neil Armstrong (right) was 38 years old when he became the first human to walk on the Moon.
Twenty unmanned Saturn rocket tests preceded the moon launches.
Apollo spacecraft had three parts: the command module, the service module and the lunar module.
Neil Armstrong (right) was the first of 12 Americans who walked on the Moon between 1969 and 1972.
Three Apollo astronauts died in a fire during a launch pad test in 1967. They were Gus Grissom, Ed White and Roger Chaffee.
The Apollo 12 crew are the only human beings to visit a robotic spacecraft beyond Earth. They visited Surveyor 3 on the Moon in 1969.
