At 06:07 UTC (09:07 Moscow time), a Vostok-K rocket carrying the Vostok 1 spacecraft lifted off from the launch complex at the Baikonur Cosmodrome. On board sat 27-year-old Soviet pilot Yuri Gagarin — the first human ever to travel into space.
The launch vehicle was derived from the R-7 intercontinental ballistic missile developed by Sergei Korolev's team. Gagarin spent more than two hours in the cabin before liftoff. His call "Poyekhali!" ("Let's go!"), spoken at the moment of separation from the pad, became one of the most famous phrases in spaceflight history.
The flight was shrouded in strict secrecy — the Soviet side only announced it to the public after Gagarin had safely returned to Earth. The risk of failure was high: it was only the third launch of this type of vehicle carrying a living payload.
From the flight transcript
Poyekhali! (Let's go!)
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