An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft. While generally reserved for professional space travelers, the term is sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and tourists.

Until 2003, astronauts were sponsored and trained exclusively by governments, either by the military, or by civilian space agencies. However, with the sub-orbital flight of the privately-funded SpaceShipOne in 2004, a new category of astronaut was created: the commercial astronaut.

For more information about Astronaut, read the full article at Wikipedia.
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