w； this new telos is within our grasp。
The pioneering psychologist William James called religion a 〃feeling of being at home in the Universe。〃 Our tendency has been； as I described in the early chapters of this book； to pretend that the Universe is how we wish our home would be； rather than to revise our notion of what's homey so it embraces the Universe。 If； in considering James' definition； we mean the real Universe； then we have no true religion yet。 That is for another time； when the sting of the Great Demotions is well behind us； when we are acclimatized to other worlds and they to us； when we are spreading outward to the stars。
The Cosmos extends； for all practical purposes； forever。 After a brief sedentary hiatus； we are resuming our ancient nomadic way of life。 Our remote descendants； safely arrayed on many worlds through the Solar System and beyond； will be unified by their mon heritage； by their regard for their home planet； and by the knowledge that； whatever other life may be； the only humans in all the Universe e from Earth。
They will gaze up and strain to find the blue dot in their skies。 They will love it no less for its obscurity and fragility。 They will marvel at how vulnerable the repository of all our potential once was； how perilous our infancy； how humble our beginnings； how many rivers we had to cross before we found our way。
ABOUT THE AUTHOR
CARL SAGAN was the David Duncan Professor of Astronomy and Space Sciences and Director of the Laboratory for Planetary Studies at Cornell University。 He played a leading role in the American space program since its inception。 He was a consultant and advisor to NASA since the 1950s； briefed the Apollo astronauts before their flights to the Moon； and was an experimenter on the Mariner； Viking； Voyager； and Galileo expeditions to the planets。 He helped solve the mysteries of the high temperature of Venus （answer： massive greenhouse effect）； the seasonal changes on Mars （answer： windblown dust）； and the reddish haze of Titan （answer： plex organic molecules）。
For his work； Dr。 Sagan received the NASA medals for Exceptional Scientific Achievement and （twice） for Distinguished Public Service； as well as the NASA Apollo Achievement Award。 Asteroid 2709 Sagan is named after him。 He was also awarded the John F。 Kennedy Astronautics Award of the American Astronautical Society； the Explorers Club 75th Anniversary Award； the Konstantin Tsiolkovsky Medal of the Soviet Cosmonauts Federation； and the Masursky Award of the American Astronomical Society （〃for his extraordinary contributions to the development of planetary science 。。。。 As a scientist trained in both astronomy and biology； Dr。 Sagan has made seminal contributions to the study of planetary atmospheres； planetary surfaces； the history of the Earth； and exobiology。 Many of the most productive planetary scientists working today are his present and former students and associates〃）。
ACKNOWLEDGMENTS
Most of the material in this book is new。 A number of chapters have evolved from articles first published in Parade magazine； a supplement to the Sunday editions of American newspapers which； with an estimated 80 million readers； may be the most widely read magazine in the world。 I am greatly indebted to Walter Anderson； the editor…in…chief； and David Currier； the executive editor； for their encouragement and editorial wisdom； and to the readers of Parade； whose letters have helped me understand where I have been clear； and where obscure； and how my arguments are received。 Portions of other chapters have emerged from articles published in Issues in Science and Technology； Discover； The Planetary Report； Scientific American； and Popular Mechanics。
Aspects of this book have been discussed with a large number of friends and colleagues； whose ments have greatly improved it。 Although there are too many to list by name； I would like to express my real gratitude to all of them。 I want especially； though； to thank Norman Augustine； Roger Bonnet； Freeman Dyson； Louis Friedman； Everett Gibson； Daniel Goldin； J。 Richard Gott III； Andrei Linde； Jon Lomberg； David Morrison； Roald Sagdeev； Steven Soter； Kip Throne； and Frederick Turner for their ments on all or part of the manuscript； Seth Kaufmann； Peter Thomas； and Joshua Grinspoon for their help with tables and graphs； and a brilliant array of astronomical artists； acknowledged at each illustration； who have permitted me to showcase some of their work。 Through the generosity of Kathy Hoyt； Al McEwen； and Larry Soderblom； I've been able to display some of the exceptional photomosiacs； airbrush maps； and other reductions of NASA images acplished at the Branch of Astrogeology； U。S。 Geological Survey。
I am indebted to Andrea Barnett； Laurel Parker； Jennifer Bland； Loren Mooney； Karenn Gobrecht； Deborah Pearlstein； and the late Eleanor York for their able technical assistance； and to Harry Evans； Walter Weintz； Ann Godoff； Kathy Rosenbloom； Andy Carpenter； Martha Schwartz； and Alan MacRobert on the production end。 Beth Tondreau is responsible for much of the design elegance on these pages。
On matters of space policy； I have benefited from discussions with other members of the board of directors of The Planetary Society； especially Bruce Murray； Louis Friedman； Norman Augustine； Joe Ryan； and the late Thomas O。 Paine。 Devoted to the exploration of the Solar System； the search for extraterrestrial life； and international missions by humans to other worlds； it is the organization that most nearly embodies the perspective of the present book。
Those readers interested in more information on this nonprofit organization； the largest space…interest group on Earth； may contact：
THE PLANETARY SOCIETY
65 N。 Catalina Avenue
Pasadena； CA 91106
Tel。： 1…800…9 WORLDS
As is true of every book I've written since 1977； I am more grateful than I can say to Ann Druyan for searching criticism and fundamental contributions both on content and style。 In the vastness of space and the immensity of time； it is still my joy to share a planet and an epoch with Annie。
REFERENCES
（a few citations and suggestions for further reading）
PLANETARY EXPLORATION IN GENERAL：
J。 Kelly Beatty and Andrew Chaiken； editors； The New Solar System； third edition （Cambridge： Cambridge University Press； 1990）。 Eric Chaisson and Steve McMillan； Astronomy Today （Englewood Cliffs； NJ： Prentice Hall； 1993）。
Esther C。 Goddard； editor； The Papers of Robert H。 Goddard （New York： McGraw…Hill； 1970） （three volumes）。
Ronald Greeley； Planetary Landscapes； second edition （New York： Chapman and Hall； 1994）。
William J。 Kaufmann III； Universe； fourth edition （New York： W。 H。 Freeman； 1993）。 Harry Y。 McSween； Jr。； Stardust to Planets （New York： St。 Martin's； 1994）。 Ron Miller and William K。 Hartmann； The Grand Tour： A Traveler's Guide to the Solar System； revised edition
（New York： Workman； 1993）。 David Morrison； Exploring Planetary Worlds （New York： Scientific American Books； 1993）。 Bruce C。 Murray； journey to the Planets （New York： W。W。 Norton； 1989）。
Jay M。 Pasachoff； Astronomy： From Earth to the Universe （New York： Saunders； 1993）。
Carl Sagan； Cosmos （New York： Random House； 1980）。
Konstantin Tsiolkovsky； The Call of the Cosmos （Moscow： Foreign Languages Publishing House； 1960） （English
translation）。
CHAPTER 3； THE GREAT DEMOTIONS
John D。 Barron and Frank J。 Tipler； The Anthropic Cosmological Principle （New York： Oxford University Press；
1986）。 A。 Linde； Particle Physics and Inflationary Cosmology （Harwood Academy Publishers； 1991）。
B。 Stewart； 〃Science or Animism？；〃 Creation /Evolution； vol。 12； no。 1 （1992）； pp。 18…19。
Steven Weinberg； Dreams of a Final Theory （New York： Vintage Books； 1994）。
CHAPTER 4； A UNIVERSE NOT MADE FOR US
Brian Appleyard； Understanding the Present： Science and the Soul of Modern Man （London： Picador/Pan Books
Ltd。； 1992）。 Passages quoted appear； in order； on the following pages： 232； 27； 32； 19； 19； 27； 9； xiv； 137；
112…113； 206； 10； 239； 8； 8。 J。 B。 Bury； History of the Papacy in the 19th Century （New York： Schocken； 1964）。 Here； as in many other
sources； the 1864 Syllabus is transcribed into its 〃positive〃 form （e。g。； 〃Divine revelation is perfect〃） rather
than as part of a list of condemned errors （〃Divine revelation is imperfect〃）。
CHAPTER 5； IS THERE INTELLIGENT LIFE ON EARTH？
Carl Sagan； W。 R。 Thompson； Robert Carlsson； Donald Gurnett； and Charles Hord； 〃A Search for Life on Earth
from the Galileo Spacecraft；〃 Nature； vol。 365 （1993）； pp。 715…721。
CHAPTER 7； AMONG THE MOONS OF SATURN
Jonathan Lunine； 〃Does Titan Have Oceans？；〃 American Scientist； vol。 82 （1994）； pp。 134…144。 Carl Sagan； W。 Reid Thompson； and Bishun N。 Khare； 〃Titan： A Laboratory for Prebiological Organic
Chemistry；〃 Accounts of Chemical Research； vol。 25 （1992）； pp。 286…292。 J。 William Schopf； Major Events in the History of Life （Boston： Jones and Bartlett； 1992）。
CHAPTER 8； THE FIRST NEW PLANET
Bernard Cohen； 〃G。 D。 Cassini and the Number of the Planets；〃 in Nature； Experiment and the Sciences；
Trevor Levere and W。 R。 Shea； editors （Dordrecht： Kluwer； 1990）。