Since our first manned space flights we have learned much about how the human body adapts to the space environment and in particular, to the absence of gravity. This book explains the how and why behind the puffy faces, nausea, and bone calcium loss so common to astronauts who experience zero gravity. It offers not only a survey of the main results of space research but also the basic concepts in human physiology necessary to better understand the effects of both long-term and short-term absence of gravity on the human body. Topics also include cosmic rays, cells, plants, embryonic development, and the origins of life on earth from a space research standpoint. INV STAT: Not yet published