We just learned about Explorer I the first satellite every launched into space by America.
The first person to ever go into outer space was Yuri Gagarin, a Russian cosmonaut.
Cosmonaut is the word the Russians used for astronauts.
(from: wikipedia - yuri gagarin)
His spacecraft was called the Vostok 1, and it did one orbit of the Earth on April 12th, 1961.
(from: wikipedia - vostok 1)