{pdf} National Academy of Sciences. Recapturing a Future for Space Exploration: Life and Physical Sciences Research for a New Era by Committee for the Decadal Survey on Biological

National Academies Press, Washington, 2011, 444 p. ? ISBN: 0309163846. More than four decades have passed since a human first set foot on the Moon. Great strides have been made in our understanding of what is required to support an enduring human presence in space, as evidenced by progressively more advanced orbiting human outposts, culminating in the current International Space Station (ISS). However, of the more than 500 humans who have so far ventured into space, most have gone only as far as near-Earth orbit, and none have traveled beyond the orbit of the Moon. Achieving humans’ further progress into the solar system had proved far more difficult than imagined in the heady days of the Apollo missions, but the potential rewards remain substantial.