Soviet cosmonaut Yuri Gagarin defied gravity and became the first man in space 55 years ago -- on April 12, 1961.

Launched on 4 October 1959, the USSR's Luna 3 revealed the far side of the Moon, showing it to be far more mountainous than the side facing the Earth. Vostok 1. Cosmonaut Yuri Gagarin became the ...

It's been 60 years since Yuri Gagarin became the first person in space. ... He completed a full orbit of the Earth on 12 April 1961 on-board the spacecraft Vostok 1.