I went into my reporting of First Contact with more than three decades of journalism and writing experience but limited knowledge of the many scientific disciplines that make up astrobiology. As a result, I was utterly dependent on the time and gracious teaching of the scores of researchers who let me into their labs and into their lives. Almost all were accustomed to speaking about their research primarily with their scientific peers, yet my early lack of knowledge about their fields and their terminology required me to ask many, many questions. I never once felt that the scientists resented my endless inquiries; instead, I found them eager to talk until their work was understood in a way that it could be accurately explained to scientists and nonscientists alike. I will be forever grateful for the education I received.
While I spoke with scores of women and men about their work, I am very much aware of the many other important and talented scientists working in astrobiology whom I did not interview or get to know. This book describes the work of a limited number of researchers, and I am sure all would say they could not have achieved the breakthroughs they did (or will) without the prior work of many others and the current work of many colleagues.
As mentioned in the book’s opening chapter, my interest in astrobiology was excited by one of its foremost practitioners—theoretical physicist and exoplanet expert Sara Seager of MIT. Her knowledge and enthusiasm helped both direct and inform me. Edward Weiler, associate administrator for NASA’s Science Directorate, also gave me the broad overview of astrobiology that I needed to get started, and the confidence that the enterprise was headed somewhere very important. Both Mary Voytek, NASA’s chief scientist for astrobiology, and Carl Pilcher, the director of the NASA Astrobiology Institute, played similar foundational roles, as did Fraser Watts and Lord Martin Rees of Cambridge University. Linda Billings, research professor, School of Media and Public Affairs of George Washington University, was instrumental as well in setting me in the right directions, as was Arthur Charo of the National Research Council. The textbook Planets and Life: The Emerging Science of Astrobiology, by Woodruff T. Sullivan III and John A. Baross, provided invaluable background understanding. And of course, every writer about astrobiology is in some way influenced by the late Carl Sagan.
The opening chapter is a compilation and interpretation of the knowledge I gleaned from my scores of interviews, in addition to readings of books and scientific papers listed in the bibliography. But a number of people stand out as especially informative and helpful in identifying major themes: Sara Seager; Steven Benner of the Foundation for Applied Molecular Evolution in Gainesville, Florida; Carol Cleland of the University of Colorado, Boulder; Tullis Onstott of Princeton University; Michael Mumma of NASA’s Goddard Space Flight Center; Steven J. Dick, former official historian for NASA; David McKay of NASA’s Johnson Space Center; Paul Butler of the Carnegie Institution of Washington; Pan Conrad of the Goddard Space Flight Center; and Christopher McKay of NASA’s Ames Research Center.
The chapter on extremophiles was anchored in the pioneering work of scientists such as John Baross of the University of Washington and John Priscu of Montana State University, but relied heavily on time spent with Tullis Onstott, Brent Christner of Louisiana State University, Gaetan Borgonie of the University of Ghent, and Lisa Pratt of Indiana University. My journey to the mines of South Africa was accomplished only with the assistance of Esta van Heerden and Derek Litthauer of the University of the Free State in Bloemfontein, South Africa, who both took me along with them and taught me along the way. Peter Doran of the University of Illinois in Chicago and Bill Stone of Stone Aerospace in Austin, Texas, explained the science and technology involved in the Lake Bonney expedition in Antarctica. In addition, the 2010 American Geophysical Union’s Chapman Conference on the Exploration and Study of Antarctic Subglacial Aquatic Environments gave me a three-day tutorial on the improbable yet central world of microbes living in ice.
Exploring the definitions of life was inspired by and aided substantially by the work of Carol Cleland and Christopher Chyba of Princeton University, and especially by the patient teaching of Cleland. In addition, Gilbert Levin, now president of Spherix and formerly a principal investigator for the NASA Viking mission, shared his information and time, as did NASA’s Michael Meyer, chief scientist for Mars missions. Penelope Boston of New Mexico Tech, Kimberly Kuhlman of the Planetary Science Institute, and Ferran Garcia-Pichel of Arizona State University explained and showed me the world of desert varnish. Steve Benner and his Foundation for Applied Molecular Evolution colleague Matt Carrigan explained synthetic biology and allowed me several days in their lab, and Gerald Joyce and Tracey Lincoln described their groundbreaking work in creating self-replicating RNA at the Scripps Research Institute.
Regarding the Miller-Urey experiment and its decades of influence, I am most indebted to Danny Glavin and Jason Dworkin of NASA’s Goddard Space Flight Center for their generous sharing of time and our trip together to the National Museum of Natural History in Washington to discuss the Murchison meteorite. They also gave me insights into the phenomenon of chirality, as did Sandra Pizzarello of Arizona State University. Jeffrey Bada of the Scripps Oceanographic Institution, Antonio Lazcano of the National Autonomous University of Mexico, and Rafael Navarro-González of the university spent substantial time teaching me, as did Pascale Ehrenfreund of the University of Leiden and George Washington University. My journey to Alaska was greatly aided by lightning experts Ronald Thomas of New Mexico Tech and his colleague Sonje Behnke, and volcanologist Steven McNutt of the Alaska Volcano Observatory. McNutt arranged for our remarkable trip to the mouth of the Mount Redoubt volcano.
Michael Mumma of Goddard Space Flight Center not only explained the complex world of spectroscopy and how he and his colleagues detected methane on Mars, but he also helped secure an invitation for me to meet him at the European Southern Observatory at Paranal, Chile. He and his colleague, Geronimo Villanueva, allowed me to join them for two nights of observing, which was both fascinating and illuminating. Laura Ventura of the ESO also helped instruct me on some of the mechanics of the telescope and astrophysics of the work. Edward Weiler of NASA described the importance of Mumma’s work in reaching an agreement with the European Space Agency for two joint missions to Mars. For the section on additional research into possible life on Mars, I relied on interviews with Paul Mahaffy of NASA’s Goddard Space Center, Steven Squyres of Cornell University, and the rich literature on the long-ago presence of water on the Martian surface, the former presence of a magnetic field, and the mineralogy of the planet. Most important, I learned firsthand from NASA’s Pan Conrad at Death Valley, the Mojave Desert, and White Mountain Peak about how to analyze habitats in extreme areas. As a member of NASA’s Mars Science Laboratory science team, which will analyze Mars for organic material and habitats potentially suitable for life, she gave me insights into how the mission will unfold. In addition, numerous presentations at the Astrobiology Science Conference of 2010 in League City, Texas, about the Martian past helped inform my reporting.
In navigating the difficult shoals of the controversies about published research asserting that extraterrestrial life had been detected in Martian and other meteorites and by the Viking Mars lander in 1976, I spent substantial time with Richard Hoover of NASA’s Marshall Space Center, David McKay of NASA’s Johnson Space Center, and Gil Levin. All three explained in great detail how and why they are convinced they did discover extraterrestrial life. Contrary views were provided by Andrew Steele of the Carnegie Institution of Washington, NASA’s Mary Voytek and Michael Meyer, Allan Treiman of the Lunar and Planetary Institute, and Rafael Navarro-González. Kathy Sawyer’s The Rock from Mars gave deeply reported and highly respected insights into the ALH 84001 Martian meteorite debate, and Henry Cooper’s The Search for Life on Mars did the same for the Viking Labeled Release controversy. Presentations at the 2010 Astrobiology Science Conference (AbSciCon) by Kathie Thomas-Keprta and Everett K. Gibson helped explain the current status of research on the famous meteorite.
The science of planet-hunting was illuminated and made fascinating primarily by Paul Butler, who invited me to spend time with him at the Anglo-Australian Observatory in Coonabarabran, Australia. His patient descriptions of the complex science helped me enormously. The paper published by Butler and Steve Vogt of the University of California at Santa Cruz on the discovery of the first exoplanet in a “habitable zone” provided the exclamation point at the end of the planet-hunting sentence. The literature on exoplanet discoveries is also rich, and I found James Kasting’s How to Find a Habitable Planet to be useful. Webster Cash of the University of Colorado, Boulder, and Remi Soummer of the Space Telescope Institute in Baltimore explained the science of occulters after I was first introduced to it by Sara Seager. The complex history of NASA’s efforts to develop a Terrestrial Planet Finder mission, which would explore for potentially habitable planets, was the subject of several presentations at AbSciCon 2010 as well.
My introduction to the issue of the “fine-tuning” of the universe occurred at Cambridge University, and came from Lord Martin Rees, history of science professor and minister Fraser Watts, and former physics professor and minister John Polkinghorne. Theoretical cosmologist Paul Davies of Arizona State University helped me in numerous ways in both interviews and his several books on the subject. Lee Smolin of the Perimeter Institute of Theoretical Physics taught me about cosmic natural selection, as did Louis Crane of Kansas State University. George Ellis of the University of Cape Town provided a religious interpretation of fine-tuning.
On the subject of the shadow biosphere and arsenic-based life in Mono Lake, I relied on information from NASA Astrobiology Institute fellow Felisa Wolfe-Simon, her colleague at the U.S. Geological Survey, Ron Oremland, Mary Voytek and microbiologist Rosie Redfield at the University of British Columbia. Reporting by Carl Zimmer in Slate and Dennis Overbye at The New York Times was also informative. In addition, I was initially introduced to the subject of the possible shadow biosphere by Paul Davies and Carol Cleland, who both shared insights into their pioneering thinking.
The literature on SETI is extensive, but firsthand reporting is not. That is why I traveled to both the Allen Array at Hat Creek, California, to see the new SETI radio telescopes, and to the Nishi-Harima Observatory in western Japan to witness a nationwide SETI observation organized by observatory director Shin-ya Narusawa, who provided much-appreciated information and insight. Frank Drake, Jill Tarter, and Douglas Vakoch of the SETI Institute spoke with me at length about current SETI projects and history. Rick Forester is the chief scientist at Hat Creek, and he also provided invaluable information. I was introduced to the controversial and fascinating subject of “active SETI” by Vakoch and listened to several presentations about it at the AbSciCon 2010 gathering.
The history of the extraterrestrial debate, and especially its religious ramifications, is well documented by NASA’s Steven Dick and the University of Notre Dame’s Michael Crowe. I am indebted to Father José Gabriel Funes, director of the Vatican Observatory, for his help regarding the 2009 Vatican conference on astrobiology, and to Notre Dame University professor Ingrid Rowland for her work on the martyred Giordano Bruno. Fraser Watts of Cambridge University also helped put issues in perspective. Margaret Race of SETI organized the NASA-sponsored 2009 conference on the implications of astrobiology, and I appreciate her willingness to have me participate and share much information. My final conclusions in chapter 10 were largely the result of my own thinking, but they were helped by discussions with Carol Cleland, Geoffrey Marcy, Paul Davies, Ed Weiler, and Sara Seager, as well as reading the works of Peter Ward, Alan Boss, and Martin Rees.