The captivating possibilities of extraterrestrial life on exoplanets, based on current scientific knowledge of existing worlds and forms of life
It is now known that we live in a galaxy with more planets than stars. The Milky Way alone encompasses 30 trillion potential home planets. Scientists Trefil and Summers bring readers on a marvelous experimental voyage through the possibilities of life--unlike anything we have experienced so far--that could exist on planets outside our own solar system.
Life could be out there in many forms: on frozen worlds, living in liquid oceans beneath ice and communicating (and even battling) with bubbles; on super-dense planets, where they would have evolved body types capable of dealing with extreme gravity; on tidally locked planets with one side turned eternally toward a star; and even on "rogue worlds," which have no star at all. Yet this is no fictional flight of fancy: the authors take what we know about exoplanets and life on our own world and use that data to hypothesize about how, where, and which sorts of life might develop. Imagined Life is a must-have for anyone wanting to learn how the realities of our universe may turn out to be far stranger than fiction.
Posing a far-reaching question what will alien life look like when humankind finds it? the coauthors of Exoplanets explore possible answers in this lively, imaginative, and accessible look at cutting-edge exobiology. The first step for physicist/science writer Trefil, and Summers, a member of NASA's New Horizon mission, is deciding how to define life. The basic definitions are broad, selected to cover every possibility imaginable so far. Next, the authors explore the clues, or "biomarkers," that hint that a planet does or did harbor life. With those basics down, the book ranges widely, exploring an exotic variety of hypothetical life that might evolve on everything from Earthlike "Goldilocks" worlds with some surface water, to stormy, entirely water-covered worlds or dark "rogue" planets adrift in space with no home star. The discussion closes with a look at some really alien possibilities life evolving in methane or ammonia instead of water, or inorganic life based on metals instead of carbon. Throughout, the spirited, nontechnical discussion is detailed enough to fascinate nonspecialist readers without overwhelming them. This is a marvelous introduction to a field fueled by both imagination and science.