Astronaut into space, Yuri Gagarin in 1961, they chose a term which anglicizes to "cosmonaut". In English-speaking nations, a professional space traveler is called an "astronaut". The term derives from the Greek words "ástron" (ἄστρον), meaning "star", and "nautes" (ναύτης), meaning "sailor". The first known use of the term "astronaut" in the modern sense was by Neil R. Jones in his 1930 short story "The Death's Head Meteor". The word itself had been known earlier; for example, in Percy Greg's 1880 book "Across the Zodiac", "astronaut" referred to a spacecraft. In "Les Navigateurs de l'Infini" (1925) by J.-H. Rosny aîné, the
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