Exploring the potential for extraterrestrial life and the origins of our own planet, this comprehensive introduction to astrobiology is updated with the latest findings. Informed by the discoveries and analyses of extrasolar planets and the findings from recent robotic missions across the solar system, scientists are rapidly replacing centuries of speculation about potential extraterrestrial habitats with real knowledge about the possibility of life outside our own biosphere—if it exists, and, if so, where. Casting new light on the biggest questions there are—how did we get here, and who else might be out there?—this third edition of Kevin W. Plaxco and Michael Gross's widely acclaimed Astrobiology incorporates a decade's worth of new developments in space to bring readers the most comprehensive, up-to-date, and engaging introduction to the field available. Plaxco and Gross examine the factors that make our Universe habitable, from the origin of chemical elements and the formation of the first galaxies and stars to the birth and composition of the planets. They describe the latest thinking about the origins of life, explain the evolution of metabolism and the development of complex organisms. In order to assess the limits for life elsewhere, they also explore life in extreme habitats and reveal how it informs the search for potential extraterrestrial habitats—ones that might support extraterrestrial life. New and updated illustrations enhance the book throughout. Sharing fascinating findings from the comet mission Dawn, the visit of New Horizons to Pluto, and the work of the Deep Carbon Observatory, which has revealed an incredible underground biosphere within our own planet, Plaxco and Gross weave together cosmology, astrophysics, geology, biochemistry, biophysics, and microbiology. From neutron star mergers to the survival skills of tardigrades, this fascinating book is an ideal primer for students or anyone curious about life and the Universe.