In this compelling book, leading scientists and historians explore the Drake Equation, which guides modern astrobiology's search for life beyond Earth. First used in 1961 as the organising framework for a conference in Green Bank, West Virginia, it uses seven factors to estimate the number of extraterrestrial civilisations in our galaxy. Using the equation primarily as a heuristic device, this engaging text examines the astronomical, biological, and cultural factors that determine the abundance or rarity of life beyond Earth and provides a thematic history of the search for extraterrestrial life. Logically structured to analyse each of the factors in turn, and offering commentary and critique of the equation as a whole, contemporary astrobiological research is placed in a historical context. Each factor is explored over two chapters, discussing the pre-conference thinking and a modern analysis, to enable postgraduates and researchers to better assess the assumptions that guide their research.

'Now, over a half century after Drake's original formulation, Douglas Vakoch and Matthew Dowd have brought together a group of scholars to assess the equation's place in the history of astrobiology … the Drake equation may reveal as much about the historical epistemology of science as it does about the ongoing search for a way to communicate with intelligent life in the universe.' Greg Eghigian, Isis

Douglas A. Vakoch is Director of Interstellar Message Composition at the SETI Institute and Professor of Clinical Psychology at the California Institute of Integral Studies. He also serves as chair of the International Academy of Astronautics Study Group on Interstellar Message Construction, and has edited numerous books in the field of astrobiology and space exploration. Matthew F. Dowd is an editor at the University of Notre Dame Press and teaches periodically on the Program of Liberal Studies. He has been instrumental in organizing Notre Dame's biennial History of Astronomy conferences and in 2011 received the Adler-Mansfield Prize for contributions to the history of astronomy.