Yuri Gagarin (9 March 1934 – 27 March 1968) was a Soviet pilot and cosmonaut. He was the 1st human to the journey into outer space when his Vostok spacecraft completed an orbit of the Earth on April 12, 1961.
It will be marked by ceremonies and a 50-gun salute at the Kremlin in Moscow.
Russian President Dmitry Medvedev said it was a "revolutionary" event that changed the world.
