The space-faring nations are heading for the human exploration of the Moon, Mars and Near-Earth Objects. They might be soon prepared with regard to technology development. But they also need to benefit from the humanities (history, philosophy, anthropology), the arts as well as the social sciences (political science, economics, law) for mastering this immense endeavour. The European Science Foundation (ESF), the European Space Agency (ESA), and the European Space Policy Institute (ESPI) have organised the first comprehensive trans-disciplinary dialogue on humans in outer space. It investigates the human quest for odysseys beyond Earth's atmosphere and reflects on the implications of the findings of extraterrestrial life. The articles in this book present, for the first time, a comprehensive analysis by all relevant disciplines responding to the questions of how, why and with what goal humans explore outer space. More than twenty experts shed light on the thrilling perspectives space exploration provides for science, technology, politics and culture.