Does life exist on other planets? This 1998 book presents the scientific basis for thinking there may be life elsewhere in the Universe. It is the first to cover the entire breadth of recent exciting discoveries, including the discovery of planets around other stars and the possibility of fossil life in meteorites from Mars. Suitable for the general reader, this authoritative book avoids technical jargon and is well illustrated throughout. It covers all the major topics, including the origin and early history of life on Earth, the environmental conditions necessary for life to exist, the possibility that life might exist elsewhere in our Solar System, the occurrence of planets around other stars and their habitability, and the possibility of intelligent extraterrestrial life. For all those interested in understanding the scientific evidence for and likelihood of extraterrestrial life, this is the most comprehensive and readable book to date.

An insider's look at the cutting-edge science of today's planet hunters In Strange New Worlds, renowned astronomer Ray Jayawardhana brings news from the front lines of the epic quest to find planets—and alien life—beyond our solar system. Only in the past two decades, after millennia of speculation, have astronomers begun to discover planets around other stars—thousands in fact. Now they are closer than ever to unraveling distant twins of the Earth. In this book, Jayawardhana vividly recounts the stories of the scientists and the remarkable breakthroughs that have ushered in this extraordinary age of exploration. He describes the latest findings--including his own—that are challenging our view of the cosmos and casting new light on the origins and evolution of planets and planetary systems. He reveals how technology is rapidly advancing to support direct observations of Jupiter-like gas giants and super-Earths—rocky planets with several times the mass of our own planet—and how astronomers use biomarkers to seek possible life on other worlds. Strange New Worlds provides an insider's look at the cutting-edge science of today's planet hunters, our prospects for discovering alien life, and the debates and controversies at the forefront of extrasolar-planet research. In a new afterword, Jayawardhana explains some of the most recent developments as we search for the first clues of life on other planets.

The field of planetary biology and chemical evolution draws together experts in astronomy, paleobiology, biochemistry, and space science who work together to understand the evolution of living systems. This field has made exciting discoveries that shed light on how organic compounds came together to form self-replicating molecules-the origin of life. This volume updates that progress and offers recommendations on research programs-including an ambitious effort centered on Mars-to advance the field over the next 10 to 15 years. The book presents a wide range of data and research results on these and other issues: The biogenic elements and their interaction in the interstellar clouds and in solar nebulae. Early planetary environments and the conditions that lead to the origin of life. The evolution of cellular and multicellular life. The search for life outside the solar system. This volume will become required reading for anyone involved in the search for life's beginnings-including exobiologists, geoscientists, planetary scientists, and U.S. space and science policymakers.

An engaging account of our quest for habitable environments, recounting fascinating recent discoveries and providing insight into future space missions.

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.

This book discusses the big questions about how the discovery of extraterrestrial life, whether intelligent or microbial, would impact society and humankind.

In the mid-1990s, astronomers made history when they began to find planets orbiting stars in the Milky Way. More than eight hundred planets have been found since then, yet none of them is anything like Earth and none could support life. Now, armed with more powerful technology, planet hunters are racing to find a true twin of Earth. Science writer Michael Lemonick has unique access to these exoplaneteers, as they call themselves, and Mirror Earth unveils their passionate quest. Unlike competitors in other races, Geoff Marcy, Bill Borucki, David Charbonneau, Sara Seager, and others actually consult and cooperate with one another. But only one will be the first to find Earth's twin. Mirror Earth tells the story of their competition.