In 1957, the Soviet Union launched Laika, a dog, into space aboard the Sputnik 2 spacecraft. The part Siberian husky, a stray dog from Moscow, became a passenger in the Union of Soviet Socialist Republics' second artificial Earth satellite, becoming the first animal to orbit Earth. Scientists on the ground used electrodes attached to her body to gather important information about the biological effects of space travel. She survived for several days, thanks to a sophisticated life-support system, but died after the batteries ran down. The Soviet Union later launched at least a dozen more dogs into space to prepare for the first manned mission. Five of these dogs died in flight.

On April 12th, 1961, Yuri Gagarin became the first human to travel into space, orbiting the Earth once before landing safely in the USSR aboard the spacecraft Vostok 1.