Behavioral, psychiatric, and sociological problems of long-duration space missions

A literature search was conducted in an effort to isolate the problems that might be expected on long-duration space missions. Primary sources of the search include short-term space flights, submarine tours, Antarctic expeditions, isolation-chamber tests, space-flight simulators, and hypodynamia studies. Various stressors are discussed including weightlessness and low sensory input; circadian rhythms (including sleep); confinement, isolation, and monotony; and purely psychiatric and sociological considerations. Important aspects of crew selection are also mentioned. An attempt is made to discuss these factors with regard to a prototype mission to Mars.