On this day in 1961 Yuri Gagarin became the first human being to travel beyond the confines of Earth aboard the Vostok 1 spacecraft. Yuri Gagarin became an international celebrity and was awarded many medals and honours, including Hero of the Soviet Union, that nation's highest honour. Although this was his only spaceflight, he served as backup crew to the Soyuz 1 mission (which ended in a fatal crash). Gagarin later became deputy training director of the Cosmonaut Training Center located in Star City outside of Moscow in Russia, which was later named after him. Gagarin died in 1968 when a MIG 15 he was piloting suddenly crashed. To this day the cause of the crash is still unknown. He was also honored by the American space program during the Apollo 11 moon mission when astronauts Neil Armstrong and Buzz Aldrin left a memorial bag containing medals commemorating Gagarin and cosmonaut Vladimir Komarov on the moon. On August 1st 1971, Apollo 15 astronauts left an aluminum sculpture known as the "Fallen Astronaut" on the surface of the Moon as a memorial to all the American astronauts and Soviet cosmonauts that died during the Space Race, with Yuri Gagarin listed among 14 others.