Alan Shepard was an American astronaut and the first person in space. He was part of the Mercury Seven, a group of astronauts chosen by NASA for the United States' first human spaceflight program. Shepard was the first American to travel into space, launching aboard the Freedom 7 spacecraft on May 5, 1961. He was also the fifth person in space overall, following Soviet cosmonauts Yuri Gagarin and Gherman Titov. Shepard's mission lasted just 15 minutes, but it was a major milestone in the history of space exploration.