Claim: John Glenn was one of the Mercury Seven.

John Herschel Glenn Jr. -LRB- July 18 , 1921 -- December 8 , 2016 -RRB- was a United States Marine Corps aviator , engineer , astronaut , and United States Senator from Ohio . In 1962 he was the first American to orbit the Earth , circling it three times . Before joining NASA , Glenn was a distinguished fighter pilot in World War II and Korea with six Distinguished Flying Crosses and eighteen clusters on his Air Medal .   He was one of the Mercury Seven , military test pilots selected in 1959 by NASA as the United States ' first astronauts . On February 20 , 1962 , Glenn flew the Friendship 7 mission ; the first American to orbit the Earth , he was the fifth person in space . He received the NASA Distinguished Service Medal , the Congressional Space Medal of Honor in 1978 , was inducted into the U.S. Astronaut Hall of Fame in 1990 , and was the last surviving member of the Mercury Seven .   After Glenn resigned from NASA in 1964 and retired from the Marine Corps the following year , he planned to run for a U.S. Senate seat from Ohio . An injury in early 1964 forced his withdrawal , and he lost a close primary election in 1970 . A member of the Democratic Party , Glenn first won election to the Senate in 1974 and served for 24 years until January 3 , 1999 .   In 1998 , still a sitting senator , Glenn was the oldest person to fly in space as a crew member of the Discovery space shuttle and the only person to fly in both the Mercury and Space Shuttle programs . He received the Presidential Medal of Freedom in 2012 .