Astronaut Astronaut 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. Although generally reserved for professional space travelers, the terms are sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and tourists. Until 2002, astronauts were sponsored and trained exclusively by governments, either by the military or by civilian space agencies. With the suborbital flight of the privately funded SpaceShipOne in 2004, a new category of astronaut was created: the commercial astronaut. The criteria for what constitutes human spaceflight vary. The Fédération
Astronaut training the ISS. The Tsukuba Space Center also includes medical facilities for assessing suitability of candidates, an isolation chamber for simulating some of the mental and emotional stressors of long duration spaceflight, and a hypobaric chamber for training in hull breach or Life Support System failure scenarios resulting in a reduction or loss of air pressure. Although official detail of the selection process for the Shenzhou program is not available, what is known is that candidates are chosen by the Chinese National Space Administration from the Chinese air force and must be between 25 and 30 years of age, with a