On March 18, 1965, the Soviet spacecraft Voshkod-2 launched with two cosmonauts on board, Alexei Leonov and Pavel Belyayev.

Two NASA astronauts aboard the International Space Station (ISS) are about to climb into their spacesuits and enter the ...

In this photo provided by NASA, astronaut Ed White performs the United States' first spacewalk on June 3, 1965, during the Gemini 4 mission. James McDivitt / AP The world’s first spacewalker was ...