Communication with Extraterrestrial Intelligence is devoted to the concepts and studies related to the science, technology, and observational techniques of communication with extraterrestrial intelligence (CETI). Topics covered range from the search for extraterrestrial intelligence (SETI) to the theory of interstellar communication; the problem of the origin of life; radio signals from extraterrestrial civilizations; and interstellar communication by neutrino beams. An infinitely expandable space radiotelescope is also described. This book is comprised of 21 chapters and opens with a discussion on the CETI activities of the International Academy of Astronautics (IAA) from 1965 to 1976 and describes the outlook for the IAA CETI Standing Committee. The following chapters sketch the background and rationale for a SETI program; the significance of the detection of signals and of information that may be contained in signals from extraterrestrial civilizations; an extended Drake's equation, the longevity-separation relation, equilibrium, inhomogeneities, and chain formation; and the physical and psychological basis for the belief that a band of frequencies called the water hole is a prime band for SETI. This monograph will appeal to practitioners in the fields of astrophysics, astronomy, planetary formation, exobiology, and biological evolution.

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.

If we send a message into space, will extraterrestrial beings receive it? Will they understand? The endlessly fascinating question of whether we are alone in the universe has always been accompanied by another, more complicated one: if there is extraterrestrial life, how would we communicate with it? In this book, Daniel Oberhaus leads readers on a quest for extraterrestrial communication. Exploring Earthlings' various attempts to reach out to non-Earthlings over the centuries, he poses some not entirely answerable questions: If we send a message into space, will extraterrestrial beings receive it? Will they understand? What languages will they (and we) speak? Is there not only a universal grammar (as Noam Chomsky has posited), but also a grammar of the universe? Oberhaus describes, among other things, a late-nineteenth-century idea to communicate with Martians via Morse code and mirrors; the emergence in the twentieth century of SETI (the search for extraterrestrial intelligence), CETI (communication with extraterrestrial intelligence), and finally METI (messaging extraterrestrial intelligence); the one-way space voyage of Ella, an artificial intelligence agent that can play cards, tell fortunes, and recite poetry; and the launching of a theremin concert for aliens. He considers media used in attempts at extraterrestrial communication, from microwave systems to plaques on spacecrafts to formal logic, and discusses attempts to formulate a language for our message, including the Astraglossa and two generations of Lincos (lingua cosmica). The chosen medium for interstellar communication reveals much about the technological sophistication of the civilization that sends it, Oberhaus observes, but even more interesting is the information embedded in the message itself. In Extraterrestrial Languages, he considers how philosophy, linguistics, mathematics, science, and art have informed the design or limited the effectiveness of our interstellar messaging.

SETI has become a popular past time with the release of the SETI @ home screen saver, which analyzes data from the Arecibo radio telescope for signs of extraterrestrial life. This book explains how likely it is that someone will be found, what kind of signals are being looked for, and how to communicate with them.