Life SciencesBiomedical SciencesPhysiologyAstrobiologyExercise PhysiologyPathophysiologyBiological Effects Of RadiationHuman HealthRadiation HealthRadiation PhysiologyFlightHuman PhysiologySpace Motion SicknessSpace Radiation Risk
Human spaceflight has progressed rapidly over the past century, achieving sustained travel beyond Earth and exposing astronauts to hazards such as radiation, microgravity, and extreme environmental conditions. Spaceflight research has deepened knowledge of human physiology in extreme environments and is expected to shape medical practice for future space explorers.
Progressing through the final decade, one pauses to reflect upon the many accomplishments of the 20th century, not the least of which is human spaceflight. In less than 100 years powered flight has been achieved and has rapidly advanced to sustained travel and exploration in outer space. The rich scientific discoveries associated with spaceflight have enhanced our understanding of human physiology in extreme environments and will, no doubt, influence the practice of medicine by those who participate in this great adventure. The hazards are many and include radiation, microgravity, motion sickness, depressurization, launch and reentry forces, meteoroids, orbital debris, changes in circadian rhythm, extreme temperature changes, isolation, cramped quarters, the potential for systems failure, and so on. Imagine, if you will, the practice of medicine in a hostile environment in which common everyday functions such as eating, exercise, work, hygiene, sleep, and even breathing present challenges to be overcome yet