Astronaut training engineers, technicians, pilots, and geologists. In addition there will be a focus on the psychological aspects of long-duration missions where crew is largely isolated. Currently a six-month mission to the ISS requires up to five years of astronaut training. This level of training is to be expected and likely to be expanded upon for future space exploration missions. It may also include in-flight training aspects. It may be possible that the ISS will be used as a long-duration astronaut training facility in the future. A powerful tool for astronaut training will be the continuing use of analog environments, including NASA
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