Yuri Gagarin was a cosmonaut for the Soviet Union. On April 12, 1961, he became the first human being to travel into space. His spacecraft was called "Vostok I" and it completed a single orbit of the earth in 1 hour and 48 minutes. The United States launched the second man into space a month later. Alan Shepard flew a suborbital flight on May 5, 1961, reaching an altitude of 115 miles during the 15-minute flight.