What determines whether complex life will arise on a planet, or even any life at all? What conditions are necessary for the emergence of intelligence? This groundbreaking book is the first to synthesize information from astronomy, biology, and paleontology, to apply what we know about the rise of life on Earth to what could possibly happen elsewhere in the Universe. Everyone who has been thrilled by the recent discoveries of extrasolar planets and the indications of life on Mars and the Jovian moon Europa will be fascinated by RARE EARTH, and its implications for those who look to the heavens for companionship.