The man is really a training astronaut named Mike Ferris, confined to an isolation room located within an aircraft hangar for 484 hours and 36 minutes, testing to see if he can stay sane cooped up in a small spacecraft for the duration of a trip to the Moon.
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(This idea was presented in Anthony Trollope's 1882 novel The Fixed Period, which envisaged a College where men retired at 67 and after a contemplative period of a year were 'peacefully extinguished' by chloroform.