April 12, 1961 the first manned space flight was made on the Vostok-1 spacecraft. In orbit Yuri Gagarin was able to conduct the simplest experiments: drinking, eating, making notes in pencil. "Putting" a pencil next to him, he found that he immediately began to swim up. Prior to his flight, it was not yet known how the human psyche will behave in space, therefore, special protection was provided so that the first astronaut would not try to control the flight of the ship in a panic. To enable manual control, he had to open a sealed envelope, inside of which lay a sheet of code, typing which on the control panel could be unblocked.At the time of landing after ejection and detachment of the airway of the descent vehicle, in the sealed Gagarin space suit the valve, through which the outside air was to flow, did not immediately open, so that the first cosmonaut nearly choked. The second danger for Gagarin could be getting on a parachute in the icy water of the Volga (was April month). But Yuri was helped by excellent preflight training - he operated the lines, he landed 2 km from the shore. This successful experiment immortalized Gagarin's name forever.