It launched on 06:07 Coordinated Universal Time (UTC), and landed about 108 minutes later at 07:55 UTC.
The flight was an historic trip because it was the first time that a human went into space.
However, the hours before the flight were not without a few problems that had to be corrected before anyone got off the ground that day in 1961.
Former top-secret papers held by the Soviets and now the Russians are about to be released on the 50th anniversary of Gagarin's first flight.
The papers are being released after the Russian space agency Roscosmos (or Russian Federal Space Agency) asked for them specifically to help celebrate the first trip of a human into space and into orbit about the Earth.
The problems that mission engineers, technicians, and controllers had to handle in the hours leading up to the launch of Gagarin include a faulty door on the capsule and an overweight combination of spacesuit, seat, and pilot.
First, the hatch on the spacecraft that Gagarin rode into space had to be repaired before the mission because of a bad sensor.
In all, 32 screws had to be removed from the door so the sensor could be fixed. It had to work so it could accurately sense if the seal around the hatch was holding or not.
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