This work would not have been possible without the support and, sometimes, direct intervention of some very smart and kind people. I must first thank Howard Yoon of Ross Yoon Agency for his working so closely with me to develop the early versions of the idea into a coherent form and his many years of help in so many, many ways. From the very beginning, my editor at W. W. Norton, Matt Weiland, saw how to make the idea and its incarnation into this book cleaner and more sharply defined. It was a great pleasure to work with him and I am deeply grateful that his skills were brought to bear on this project. Simply put, he is a great editor. I am also grateful to have had Remy Cawley on the W. W. Norton team. In editing, copyediting, and managing the image process, her precision and thoroughness were essential. I was also lucky to have two wonderful University of Rochester undergraduates working with me as assistants on the book. Molly Finn worked tirelessly on fact checking and accumulating proper references and reference forms. Elise Morgan endured a crazy autumn tracking down images and permissions. Both showed remarkable skills for young scholars, and I was lucky to have found their help.
For a scientist, it is always a little frightening to write about topics that are not squarely in the domain of your research specialty. For me, this included not only sciences like atmospheric chemistry, but also the amazing history of the discoveries I wanted to explore in the book. I bear full responsibility for any mistakes made in the text. In trying to get the story right, though, I was helped by many scientists who were generous with their time. In particular, my collaborator Woody Sullivan at the University of Washington provided many fine insights into the manuscript. My gratitude to him runs very deep. Jason Wright of Penn State gave an early version of the book a thorough and deep reading. Not only did he make the book more accurate, but he also drove me to think more deeply about a number of topics on exo-civilizations. Jill Tarter not only gave me a number of great interviews, but also provided excellent feedback on the manuscript. I am equally grateful to Donald Canfield, both for interviews on atmospheric chemistry and his review of the chapter on Earth science. James Kasting of Penn State and Lee Murray of the University of Rochester provided excellent feedback on the climate and Earth science sections as well. Robert Haberle was generous with his time in explaining the history of Mars climate modeling and reviewing the chapter on solar system exploration.
I am also grateful to Soren Gregersen, whom I bothered a number of times to tell me his stories of being a Boy Scout and living out on the Greenland ice sheet with the US military at Camp Century. I am equally grateful to Natalie Batalha and Bill Borucki for giving me their time for interviews.
There are also many people I have to thank just for their intellectual companionship. Robert Pincus and Paul Green are always at the top of the list on any topic for me. My PhD advisor and continuing collaborator Bruce Balick has always been a source of good advice and ideas. I also had many excellent conversations with my colleagues at the University of Rochester: Dan Watson, Eric Blackman, Alice Quillen, Eric Mamejek, Judy Pipher, and Bill Forrest. Also, I must thank my collaborators on the work described in this book: Woody Sullivan, Marina Alberti, Axel Kleidon, and Jonathan Carroll-Nellenback. Ongoing discussions with Evan Thompson were also fun and helpful. Writing on these topics for both NPR and the New York Times gave me a first chance to cast the ideas in non-scientific language. I am very grateful to Jamie Reyerson at the Times, as well as Meghan Sullivan and Justine Kenin at NPR.
Finally, I am particularly grateful for my NPR blog co-founder, collaborator, and friend Marcelo Gleiser, who provided the opportunity to spend time at the Institute for Cross Disciplinary Engagement at Dartmouth, where some of this book was written. Thank you, Marcelo.
Finally, I must thank my children, Sadie and Harrison, as well as my brother-in-law, Hendrik Helmer, for making me laugh . . . a lot. And always, always, always, I thank the stars for my wife, Alana Cahoon, without whom none of this would matter.