An astronaut (in the U.S.), cosmonaut (in Russia and many ex-Soviet satellite states), or taikonaut (in China) is a person trained for a spaceflight program to command, pilot, or serve as a crew member of a spacecraft. While generally reserved for professional space travelers, the terms are sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and tourists.
The criteria for what constitutes human spaceflight vary. The Fédération Aéronautique Internationale (FAI) Sporting Code for astronautics recognizes only flights that exceed an altitude of 100 kilometers (62 mi). In the United States, professional, military, and commercial astronauts who travel above an altitude of 50 miles (80 km) are awarded astronaut wings.
Starting in the 1950s up until 2002, astronauts were sponsored and trained exclusively by governments, either by the military or by civilian space agencies. With the sub-orbital flight of the privately funded SpaceShipOne in 2004, a new category of astronaut was created: the commercial astronaut. (The first non-government astronaut flew in 1984.)