In April 2010, fifty years to the month after the first experiment in the Search for Extraterrestrial Intelligence (SETI), scholars from a range of disciplines—including astronomy, mathematics, anthropology, history, and cognitive science—gathered at NASA's biennial Astrobiology Science Conference (AbSciCon) for a series of sessions on the search for intelligent life. This book highlights the most recent developments in SETI discussed at that conference, emphasizing the ways that SETI has grown since its inception. The volume covers three broad themes: First, leading researchers examine the latest developments in observational SETI programs, as well as innovative proposals for new search strategies and novel approaches to signal processing. Second, both proponents and opponents of "Active SETI" debate whether humankind should be transmitting intentional signals to other possible civilizations, rather than only listening. Third, constructive proposals for interstellar messages are juxtaposed with critiques that ask whether any meaningful exchange is possible with an independently evolved civilization, given the constraints of contact at interstellar distances, where a round-trip exchange could take centuries or millennia. As we reflect on a half-century of SETI research, we are reminded of the expansion of search programs made possible by technological and conceptual advances. In this spirit of ongoing exploration, the contributors to this book advocate a diverse range of approaches to make SETI increasingly more powerful and effective, as we embark on the next half-century of searching for intelligence beyond Earth.

It is statistically unlikely that humans are the only intelligent species in the universe. Nothing about the others will be known until contact is made beyond a radio signal from space that merely tells us they existed when it was sent. That contact may occur tomorrow, in a hundred years, or never. If it does it will be a high-risk scenario for humanity. It may be peaceful or hostile. Relying on alien altruism and benign intentions is wishful thinking. We need to begin identifying as a planetary species, and develop a global consensus on how to respond in either scenario.

Astronomers around the world are pointing their telescopes toward the heavens, searching for signs of intelligent life. If they make contact with an advanced alien civilization, how will humankind respond? In thinking about first contact, the contributors to this volume present new empirical and theoretical research on the societal dimensions of the Search for Extraterrestrial Intelligence (SETI). Archaeologists and astronomers explore the likelihood that extraterrestrial intelligence exists, using scientific insights to estimate such elusive factors as the longevity of technological societies. Sociologists present the latest findings of novel surveys, tapping into the public’s attitudes about life beyond Earth to show how religion and education influence beliefs about extraterrestrials. Scholars from such diverse disciplines as mathematics, chemistry, journalism, and religious studies offer innovative solutions for bridging the cultural gap between human and extraterrestrial civilizations, while recognizing the tremendous challenges of communicating at interstellar distances. At a time when new planets are being discovered around other stars at an unprecedented rate, this collection provides a much needed guide to the human impact of discovering we are not alone in the universe.

Addressing a field that has been dominated by astronomers, physicists, engineers, and computer scientists, the contributors to this collection raise questions that may have been overlooked by physical scientists about the ease of establishing meaningful communication with an extraterrestrial intelligence. These scholars are grappling with some of the enormous challenges that will face humanity if an information-rich signal emanating from another world is detected. By drawing on issues at the core of contemporary archaeology and anthropology, we can be much better prepared for contact with an extraterrestrial civilization, should that day ever come.

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.

Originally published in Great Britain by Profile Books Ltd, 2016.

“Refreshing . . . A penetrating analysis of the assumptions that underlie SETI and the entire enterprise of searching for life beyond Earth.” —Chris McKay, Nature Fifty years ago, a young astronomer named Frank Drake first pointed a radio telescope at nearby stars in the hope of picking up a signal from an alien civilization. Thus began one of the boldest scientific projects in history, the Search for Extraterrestrial Intelligence (SETI). After a half-century of scanning the skies, however, astronomers have little to report but an eerie silence—eerie because many scientists are convinced that the universe is teeming with life. Physicist and astrobiologist Paul Davies has been closely involved with SETI for three decades and chairs the SETI Post-Detection Taskgroup, charged with deciding what to do if we’re suddenly confronted with evidence of alien intelligence. He believes the search so far has fallen into an anthropocentric trap—assuming that an alien species will look, think, and behave much like us. In this provocative book Davies refocuses the search, challenging existing ideas of what form an alien intelligence might take, how it might try to communicate with us, and how we should respond if it does. “Paul Davies gives us a panoramic view of the quickening search for cosmic company—a fascinating tale stuffed with novel ideas about the nature of intelligence far beyond our own.” —Seth Shostak, Senior Astronomer, SETI Institute “An immensely readable investigation of the SETI enterprise . . . [A] wonderful book.” —New Scientist “A far-ranging look at what might happen here on Earth when we make first contact. Highly recommended for both science fiction and astronomy buffs.” —Publishers Weekly