Communication with Extraterrestrial Intelligence (CETI) , livre ebook

Communication with Extraterrestrial Intelligence
Edited by Douglas A. Vakoch

Published by State University of New York Press, Albany
© 2011 State University of New York
All rights reserved
Printed in the United States of America
No part of this book may be used or reproduced in any manner whatsoever without written permission. No part of this book may be stored in a retrieval system or transmitted in any form or by any means including electronic, electrostatic, magnetic tape, mechanical, photocopying, recording, or otherwise without the prior permission in writing of the publisher.
For information, contact State University of New York Press, Albany, NY www.sunypress.edu
Production by Ryan Morris Marketing by Michael Campochiaro
Library of Congress Cataloging-in-Publication Data
Communication with extraterrestrial intelligence (ceti) / edited by Douglas A. Vakoch.
       p. cm.
Includes bibliographical references and index.
ISBN 978-1-4384-3793-4 (hardcover : alk. paper)
ISBN 978-1-4384-3794-1 (pbk. : alk. paper)
1. Life on other planets. 2. Interstellar communication. I. Vakoch, Douglas A.
QB54.C653 2011
576.8'39—dc22 2010046427
10 9 8 7 6 5 4 3 2 1

To Frank Drake
Honoring a half century leading the Search for Extraterrestrial Intelligence
Preface
Just over fifty years ago, in April 1960, astronomer Frank Drake conducted Project Ozma, the first experiment to search for radio signals from extraterrestrial civilizations. Although we have not found evidence of intelligence beyond Earth in the intervening decades, our understanding of the cosmos has increased tremendously. As merely two examples, we now know that planets circle other stars in abundance and that life can survive in harsh environments ranging from the cores of nuclear reactors to the vacuum of outer space. It is fitting, then, that as we search for signs of extraterrestrial technologies we should do so in the broader context of astrobiology, the discipline that studies the origin, evolution, distribution, and future of life in the universe.
This book arose from the most recent biennial Astrobiology Science Conference (AbSciCon), organized by the National Aeronautics and Space Administration (NASA) and held the last week of April 2010. Chapters in this volume cover three broad themes in the Search for Extraterrestrial Intelligence (SETI). 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. Next, both proponents and opponents of “Active SETI” debate whether humankind should be transmitting intentional signals to other possible civilizations, rather than only listening. Finally, 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.
Those familiar with the history of interstellar communication will recall an earlier conference when reading the title of this book. The first major international conference on interstellar communication, jointly sponsored by the U.S. National Academy of Science and the USSR Academy of Sciences, was held in Soviet Armenia in 1971. The proceedings of that joint meeting were published as Communication with Extraterrestrial Intelligence (CETI) —the preferred name for interstellar communication in the early 1970s (Sagan 1973). Both of these conferences recognized the importance of including perspectives from multiple fields in the physical sciences, social sciences, and humanities. Participants of the 1971 meeting covered a range of disciplines beyond the usual gathering of astronomers and engineers, and included representatives of fields such as anthropology, history, and linguistics. Similarly, the three “Search for Intelligent Life” sessions at AbSciCon 2010 encouraged cross-disciplinary dialogue by including scholars from all of these disciplines and more, as indicated in the following chapters.
The use of “communication” in the title of this book captures the potentially bidirectional nature of an exchange between civilizations, albeit over intergenerational timescales, as well as the interpretive challenges of designing and decoding the messages that are exchanged. The present volume covers a range of topics too often ignored by recent treatments of SETI, which have emphasized only the science and technology of listening for signals from other civilizations. This book complements the traditional focus on receiving signals by also analyzing how and why humankind might begin transmitting in earnest, as well as grappling with the complexities of making ourselves understood.
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. Project Ozma searched in a single radio channel; thanks to advances in computing, current searches can scan millions of frequencies per second, and with much greater sensitivity. So too have we broadened our search strategies, complementing the long-standing emphasis on detecting radio signals with new searches for brief yet powerful laser pulses. 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.
Douglas A. Vakoch
Mountain View and San Francisco, California

Reference
Sagan, Carl, ed. 1973. Communication with Extraterrestrial Intelligence (CETI) . Cambridge: MIT Press.
Foreword
AbSciCon—the Astrobiology Science Conference ( http://www.lpi.usra.edu/meetings/abscicon2010/ )—is like Woodstock for astrobiologists. Every two years, the rock stars of this field gather together to report on progress in their studies of the origin and evolution of life on Earth, planetary habitability, and the search for evidence of extraterrestrial life.
More than seven hundred astrobiologists came to AbSciCon 2010, traveling from every continent—including Africa and Antarctica, where astrobiology field research is ongoing—for this science “jam” in League City, Texas.
Recent research findings relevant to astrobiology and on the AbSciCon agenda include evidence of past and perhaps present liquid water on Mars as well as an ice-covered liquid water ocean on Europa, the discovery of hundreds of extrasolar planets, observations of plumes of water-ice particles erupting from Saturn's moon Enceladus, the possibility of prebiotic chemistry on and liquid water beneath the surface of titan, and identification of new forms of microbial life in an ever-widening range of extreme Earth environments.
Enduring and widespread interest in the origin and evolution of life and the possibility of extraterrestrial life is—to resort to cliché—both a blessing and a curse. This broad, deep, cross-cultural engagement with the subject adds strength to the scientific rationale for astrobiology research and provides a great opportunity to foster science education with people of all ages.
That's the blessing part. Here's the curse part: the scientific definition of astrobiology is not necessarily the same as the public conception of astrobiology.
One aspect of the study of the origin and evolution of life in the universe that scientists have not yet found a way to adequately explain to nonexpert audiences is the vast chasm that stretches between our understanding of the emergence of life and the emergence of intelligence in life. Nonexperts have far less trouble than scientists do in condensing and simplifying the immense “spaces” of time and complexity that lead to prebiotic chemistry and then to life, to molecules and then to cells, and to microbial life and then to intelligent life. And it's not because they're ignorant. It's because they're not scientists. They're not trained to think like scientists. And they don't need to be.
The terms astrobiology and SETI —the search for extraterrestrial intelligence—are widely recognized inside and outside the scientific community. What these terms mean to people outside the community is something that we inside the scientific community might do well to understand, and explain, better than we do.
In the 1980s, the U.S. National Aeronautics and Space Administration (NASA) began a SETI research program culminating in the initiation of a search project in 1992, listening for radio signals originating from extraterrestrial technology. In 1993, Congress terminated the program, and NASA bowed out of the SETI enterprise. In the United States, since then, SETI work is privately funded. NASA's astrobiology program now funds research on the evolution of complex life, but not the evolution of intelligence.
In popular culture, nonetheless, boundaries between the scientific search for evidence of extraterrestrial life and SETI—and, for many out there on the fringes of credibility, even “UFOlogy”—are blurred or even erased altogether. Continuing interest in the subjects contributes to demand for popular depictions of them that are highly speculative and, sometimes, even a bit scary.
Adding to the complexity of the educational challenge facing astrobiologists is that, for experts and nonexperts as well, a wide range of opinions exists on exactly what “life” is, and what “intelligence” is.
Many pop culture takes on extraterrestrial life—or, more colloquially, aliens—appear to rest on the assumptions that life is common in the universe, and like us, and that the evolution of intelligence is easy.
About a week before the commencement of AbSciCon 2010, on April 26, the mass media widely reported remarks by renowned physicist Stephen Hawking that intelligent extraterrestrial life could be dangerous to Earthlings.