Chris Hadfield is one of the most seasoned and accomplished astronauts in the world. In May, Hadfield returned to Earth after serving as Commander of the International Space Station, where he and his crew lived for six months (it was his third trip). The top graduate of the U.S. Air Force test pilot school in 1988 and U.S. Navy test pilot of the year in 1991, Hadfield was selected to be an astronaut in 1992.