While we worry over the depletion of the earth's natural resources, the pollution of our planet, and the challenges presented by the earth's growing population, billions of dollars worth of metals, fuels, and life-sustaining substances await us in nearby space. In this visionary book, noted planetary scientist John S. Lewis explains how we can mine these precious metals from the asteroids, comets, and planets in our own solar system for use in space construction projects. And this is just one of the possibilities. Join John S. Lewis as he contemplates milking the moons of Mars for water and hollowing out asteroids for space-bound homesteaders,all while demonstrating the economic and technical feasibility of plans that were once considered pure fiction.