John Glenn was a NASA astronaut. He was part of the first group of astronauts NASA picked. He was the first American to orbit Earth. He also became a U.S. senator. Later, he became the oldest person to fly in space. John Glenn was born in Ohio. He was in college when World War II started. Glenn left school to fight in the war. He became a Marine pilot. Later, he trained other pilots. He also fought in the Korean War. After Korea, he became an airplane test pilot. In 1957, Glenn set a speed record when he flew from Los Angeles to New York in less than 3 1/2 hours.

In 1959 Glenn was chosen to be a member of the first group of the National Aeronautics and Space Administration's (NASA) astronauts. On February 20, 1962, he became the first American astronaut to orbit Earth aboard Mercury 6. In January 1963, Glenn specialized in the design and development of spacecraft and flight control systems for Project Apollo. He retired from NASA and the Marine Corps as a colonel in 1964 and was elected a U.S. senator from Ohio in November 1974.