Yuri Gagarin joined the Soviet Air Force in 1955 and graduated with honors from the Soviet Air Force Academy in 1957 .
Yuri Alexeyevich Gagarin ( 9 March 1934 -- 27 March 1968 ) was a Soviet cosmonaut and the first human to orbit the earth .
cosmonaut   joined the Soviet Air Force in 1955 and graduated with honors from the Soviet Air Force Academy in 1957 .
Yuri Alexeyevich Gagarin ( 9 March 1934 -- 27 March 1968 ) was a Soviet cosmonaut and the first human to orbit the earth .