In a 1950 conversation at Los Alamos, four world-class scientists generally agreed, given the size of the Universe, that advanced extraterrestrial civilizations must be present. But one of the four, Enrico Fermi, asked, "If these civilizations do exist, where is everybody?" Given the fact that there are perhaps 400 million stars in our Galaxy alone, and perhaps 400 million galaxies in the Universe, it stands to reason that somewhere out there, in the 14 billion-year-old cosmos, there is or once was a civilization at least as advanced as our own. Webb discusses in detail the 50 most cogent and intriguing solutions to Fermi's famous paradox.

The inspiration for the Netflix series 3 Body Problem! Over 1 million copies of the Three-Body Problem series sold in North America PRAISE FOR THE THREE-BODY PROBLEM SERIES: “A mind-bending epic.”—The New York Times • “War of the Worlds for the 21st century.”—The Wall Street Journal • “Fascinating.”—TIME • “Extraordinary.”—The New Yorker • “Wildly imaginative.”—Barack Obama • “Provocative.”—Slate • “A breakthrough book.”—George R. R. Martin • “Impossible to put down.”—GQ • “Absolutely mind-unfolding.”—NPR • “You should be reading Liu Cixin.”—The Washington Post The Dark Forest is the second novel in the groundbreaking, Hugo Award-winning series from China's most beloved science fiction author, Cixin Liu. In The Dark Forest, Earth is reeling from the revelation of a coming alien invasion-in just four centuries' time. The aliens' human collaborators may have been defeated, but the presence of the sophons, the subatomic particles that allow Trisolaris instant access to all human information, means that Earth's defense plans are totally exposed to the enemy. Only the human mind remains a secret. This is the motivation for the Wallfacer Project, a daring plan that grants four men enormous resources to design secret strategies, hidden through deceit and misdirection from Earth and Trisolaris alike. Three of the Wallfacers are influential statesmen and scientists, but the fourth is a total unknown. Luo Ji, an unambitious Chinese astronomer and sociologist, is baffled by his new status. All he knows is that he's the one Wallfacer that Trisolaris wants dead. The Three-Body Problem Series The Three-Body Problem The Dark Forest Death's End Other Books by Cixin Liu Ball Lightning Supernova Era To Hold Up the Sky The Wandering Earth A View from the Stars At the Publisher's request, this title is being sold without Digital Rights Management Software (DRM) applied.

In the vein of Randall Munroe's What If? meets Brian Green's Elegant Universe, a senior writer from Space.com leads readers on a wild ride of exploration into the final frontier, investigating what's really "out there." We've all asked ourselves the question. It's impossible to look up at the stars and NOT think about it: Are we alone in the universe? Books, movies and television shows proliferate that attempt to answer this question and explore it. In Out There Space.com senior writer Dr. Michael Wall treats that question as merely the beginning, touching off a wild ride of exploration into the final frontier. He considers, for instance, the myriad of questions that would arise once we do discover life beyond Earth (an eventuality which, top NASA officials told Wall, is only drawing closer). What would the first aliens we meet look like? Would they be little green men or mere microbes? Would they be found on a planet in our own solar system or orbiting a star far, far away? Would they intend to harm us, and if so, how might they do it? And might they already have visited? Out There is arranged in a simple question-and-answer format. The answers are delivered in Dr. Wall's informal but informative style, which mixes in a healthy dose of humor and pop culture to make big ideas easier to swallow. Dr. Wall covers questions far beyond alien life, venturing into astronomy, physics, and the practical realities of what long-term life might be like for we mere humans in outer space, such as the idea of lunar colonies, and even economic implications. Dr. Wall also shares the insights of some of the leading lights in space exploration today, and shows how the next space age might be brighter than ever./DIV

Due to its specific chemical and physical properties, water is essential for life on Earth. And it is assumed that this would be the case for extraterrestrial life as well. Therefore it is important to investigate where water can be found in the Universe. Although there are places that are completely dry, places where the last rainfall happened probably several 100 million years ago, surprisingly this substance is quite omnipresent. In the outer solar system the large satellites of Jupiter and Saturn are covered by a thick layer of ice that could be hiding a liquid ocean below. This of course brings up the question of whether the recently detected extrasolar planets could have some water on their surfaces and how we can detect this. Water molecules are also found in interstellar gas and dust clouds. This book begins with an introductory chapter reviewing the physical and chemical properties of water. Then it illuminates the apparent connection between water and life. This is followed by chapters dealing with our current knowledge of water in the solar system, followed by a discussion concerning the potential presence and possible detection of water on exoplanets. The signature of water in interstellar space and stars are reviewed before the origin of water in the Universe is finally discussed. The book ends with an appendix on detection methods, satellite missions and astrophysical concepts touched upon in the main parts of the book. The search for water in the Universe is related to the search for extraterrestrial life and is of fundamental importance for astrophysics, astrobiology and other related topics. This book therefore addresses students and researchers in these fields.

A rigorous and scientific analysis of the myriad possibilities of life beyond our planet. ÒAre we alone in the universe?Ó This tantalizing question has captivated humanity over millennia, but seldom has it been approached rigorously. Today the search for signatures of extraterrestrial life and intelligence has become a rapidly advancing scientific endeavor. Missions to Mars, Europa, and Titan seek evidence of life. Laboratory experiments have made great strides in creating synthetic life, deepening our understanding of conditions that give rise to living entities. And on the horizon are sophisticated telescopes to detect and characterize exoplanets most likely to harbor life. Life in the Cosmos offers a thorough overview of the burgeoning field of astrobiology, including the salient methods and paradigms involved in the search for extraterrestrial life and intelligence. Manasvi Lingam and Abraham Loeb tackle three areas of interest in hunting for life Òout thereÓ: first, the pathways by which life originates and evolves; second, planetary and stellar factors that affect the habitability of worlds, with an eye on the biomarkers that may reveal the presence of microbial life; and finally, the detection of technological signals that could be indicative of intelligence. Drawing on empirical data from observations and experiments, as well as the latest theoretical and computational developments, the authors make a compelling scientific case for the search for life beyond what we can currently see. Meticulous and comprehensive, Life in the Cosmos is a master class from top researchers in astrobiology, suggesting that the answer to our age-old question is closer than ever before.

The Great Silence explores the multifaceted problem named after the great Italian physicist Enrico Fermi and his legendary 1950 lunchtime question "Where is everybody?" In many respects, Fermi's paradox is the richest and the most challenging problem for the entire field of astrobiology and the Search for ExtraTerrestrial Intelligence (SETI) studies. This book shows how Fermi's paradox is intricately connected with many fields of learning, technology, arts, and even everyday life. It aims to establish the strongest possible version of the problem, to dispel many related confusions, obfuscations, and prejudices, as well as to offer a novel point of entry to the many solutions proposed in existing literature. Ćirković argues that any evolutionary worldview cannot avoid resolving the Great Silence problem in one guise or another.

Extraterrestrial Altruism examines a basic assumption of the Search for Extraterrestrial Intelligence (SETI): that extraterrestrials will be transmitting messages to us for our benefit. This question of whether extraterrestrials will be altruistic has become increasingly important in recent years as SETI scientists have begun contemplating transmissions from Earth to make contact. Technological civilizations that transmit signals for the benefit of others, but with no immediate gain for themselves, certainly seem to be altruistic. But does this make biological sense? Should we expect altruism to evolve throughout the cosmos, or is this only wishful thinking? Is it dangerous to send messages to other worlds, as Stephen Hawking has suggested, or might humankind benefit from an exchange with intelligence elsewhere in the galaxy? Would extraterrestrial societies be based on different ethical principles, or would we see commonalities with Earthly notions of morality? Extraterrestrial Altruism explores these and related questions about the motivations of civilizations beyond Earth, providing new insights that are critical for SETI. Chapters are authored by leading scholars from diverse disciplines—anthropology, astronomy, biology, chemistry, computer science, cosmology, engineering, history of science, law, philosophy, psychology, public policy, and sociology. The book is carefully edited by Douglas Vakoch, Director of Interstellar Message Composition at the SETI Institute and professor of clinical psychology at the California Institute of Integral Studies. The Foreword is by Frank Drake. This interdisciplinary book will benefit everybody trying to understand whether evolution and ethics are unique to Earth, or whether they are built into the fabric of the universe.