Imagined Life: A Speculative Scientific Journey among the Exoplanets in Search of Intelligent Aliens, Ice Creatures, and Supergravity Animals

by James Trefil, Michael Summers

Overview

The captivating possibilities of extraterrestrial life on exoplanets, based on current scientific knowledge of existing worlds and forms of life

2023 Canopus Awards for Interstellar Writing Finalist

It is now known that we live in a galaxy with more planets than stars. The Milky Way alone encompasses 30 trillion potential home planets. Scientists Trefil and Summers bring readers on a marvelous experimental voyage through the possibilities of life—unlike anything we have experienced so far—that could exist on planets outside our own solar system.

Life could be out there in many forms: on frozen worlds, living in liquid oceans beneath ice and communicating (and even battling) with bubbles; on super-dense planets, where they would have evolved body types capable of dealing with extreme gravity; on tidally locked planets with one side turned eternally toward a star; and even on "rogue worlds," which have no star at all. Yet this is no fictional flight of fancy: the authors take what we know about exoplanets and life on our own world and use that data to hypothesize about how, where, and which sorts of life might develop. Imagined Life is a must-have for anyone wanting to learn how the realities of our universe may turn out to be far stranger than fiction.

Product Details

ISBN-13:	9781588346643
Publisher:	Smithsonian Institution Press
Publication date:	09/17/2019
Pages:	240
Sales rank:	650,754
Product dimensions:	6.10(w) x 9.00(h) x 1.00(d)

About the Author

MICHAEL SUMMERS is a planetary scientist and professor of physics and astronomy at George Mason University. Since 1989, he has served on the mission teams of several NASA space probes in the role of science planning and interpretation of spacecraft observations. He is currently a coinvestigator on the NASA New Horizons mission to the Pluto-Charon double planet, where he serves as the deputy lead of the Atmospheres Theme Team. JAMES TREFIL is Clarence J. Robinson Professor of Physics at George Mason University. He has written more than 50 books on science for a general audience. His writing has won the American Institute of Physics Science Writing Award, the American Association for the Advancement of Science Westinghouse Science Journalism Award, and other honors.

Table of Contents

Preface 1

1 The Unexpected Galaxy 5

2 Opportunities and Constraints: A Universe of Laws 11

3 Life: What Is It? 25

4 The Rules of the Game: How Every Living System Has to Work 35

5 Looking for Life: Is It Really Out There? 51

6 Iceheim: Life in the Deep Freeze 65

7 Nova Europa: The Ocean beneath the Ice 81

9 Neptunia: Water, Water Everywhere 93

9 Goldilocks World: Just Like Us 107

10 Halo: Life at the Terminator 117

11 Lonesome: All by Itself 129

12 Big Boy: The Heavy One 143

13 TRAPPIST-I: A Crowded System 155

14 A Closer Look: It Gets Even Stranger 169

15 Life That Is Not Like Us: What If We're Not the Only Kind? 181

16 Life That Is Really Not Like Us: It Can Get Pretty Weird 195

17 Open Questions 211

A Final Word 225

Index 227

Editorial Reviews

PUBLISHERS WEEKLY
Starred Review. "Posing a far-reaching question—what will alien life look like when humankind finds it?—the coauthors of Exoplanets explore possible answers in this lively, imaginative, and accessible look at cutting-edge exobiology. This is a marvelous introduction to a field fueled by both imagination and science." 

BOOKLIST
"As galactic tour guides, the authors demonstrate an infectious, playful curiosity alongside their technical prowess, maintaining a light touch with some heavy science. Will appeal to sf newcomers and budding space nerds."

LIBRARY JOURNAL
"This relatively easy read is an appealing addition to the growing body of recent works addressing the possibility of extraterrestrial life. VERDICT Both popular science and sf readers will enjoy this extrapolative natural history."

KIRKUS REVIEWS
"The prose is straightforward, and the authors make the potentialities of exoplanet life intriguingly real. [...] A curiosity-whetting investigation of imagined life beyond our world."

SCIENCE NEWS
"In Imagined Life, physicist James Trefil and planetary scientist Michael Summers set out on a safari through the cosmos, conjuring up the menagerie that might inhabit some of the thousands of exoplanets discovered thus far. Many of the book’s chapters explore potential life on various types of worlds, each vastly unlike Earth. Though fanciful and fun, the pair’s efforts are grounded in science. [...] Imagined Life is an amazingly fun read. While musing about how life — and even technological civilizations — might evolve and thrive on other worlds, Trefil and Summers slip in tons of info about how life on Earth came to be."

THE SPACE REVIEW
“Imagined Life, a speculative romp by two scientists that examines what life might be like on worlds very different from Earth. Trefil and Summers, a physicist and planetary scientist, respectively, at George Mason University, spend the first few chapters providing an overview of the science of life beyond Earth, from astronomy to biology. The fun really begins, though, when they examine a range of hypothetical worlds and their ability to support life.” 

THE PLANETARY SOCIETY
Emily Lakdawalla
“At the outset, Trefil and Summers’ book is an excellent introduction to the basic ideas of the study of astrobiology, explaining what experiments have shown us so far, what scientists are searching for, and the underlying physics and chemistry. The language is very accessible, always emphasizing the questions scientists are asking, how we’ve discovered answers, and how much we still don’t know.” 

SCIFI MIND
"It’s an interesting speculative roam that stays within the realm of what’s known about the formation of life and enlarges carefully beyond the bounds of current knowledge. It’s an excellent primer for both reader and writer to test the plausibility of many fictional worlds and their inhabitants." 

From the Publisher

08/01/2019

Following up Exoplanets: Diamond Worlds, Super Earths, Pulsar Planets, and the New Search for Life Beyond Our Solar System, astronomers Trefil and Summers examine how the laws of chemistry and physics would shape the evolution of life and civilization on unusual worlds. Their survey includes an internally heated "snowball," a tidally locked windswept planet, and four (renamed) theoretical celestial bodies featured in their previous work. While cautioning that terrestrial biases might lead us to overlook unusual life forms, the authors openly indulge in "water chauvinism" (even though other liquids might substitute as biochemical solvents elsewhere in the universe) and "chemical chauvinism" (although it's possible that complex structures could evolve through purely electromagnetic processes). Exoplanets' carbon, stellar, and surface chauvinisms also reemerge. NASA's striking "Exoplanet Travel Bureau" graphics and amusing discussions by hidebound space alien academics, incredulous that anything could survive on planets different from theirs, offset a dull chapter enumerating already discovered extrasolar planets. This relatively easy read is an appealing addition to the growing body of recent works addressing the possibility of extraterrestrial life. VERDICT Both popular science and sf readers will enjoy this extrapolative natural history.—Nancy R. Curtis, Univ. of Maine Lib., Orono

Library Journal

2019-06-23
Are we alone in the universe? Two well-known astronomers tackle the possibilities in this tour of exoplanets.

We know of only one planet on which life exists—Earth—but is life an everyday chemical and physical reaction in the universe or a unique fluke? We have a pretty good idea of some of the steps that led to life on Earth and a firm understanding of how it evolved since then. So how does this apply to the types of exoplanets we may encounter? Would life develop there as it did on Earth? How different could it be? Given the complexity and diversity of exoplanets we have found, will the answers be correspondingly complex and diverse? These are some of the questions approached by George Mason University physics and astronomy professors Trefil and Summers (co-authors: Exoplanets, 2018, etc.) in this sober yet enervating examination of possible life scenarios on a variety of exoplanet settings. First, the authors define life, which can be handled as a list (adaptation, growth, homeostasis, metabolism, organization, reproduction, responsiveness), a process (the NASA definition is "a self-sustaining chemical system capable of Darwinian evolution"), or in terms of thermodynamics. The authors then take these definitions and apply them to a variety of possible planets: one with a rocky mantle and a metallic core overlaid with ice; one with an ocean beneath ice; in another, a land-and-water combination, etc. They probe each scenario to imagine how life could have taken shape given the opportunities and constraints. Trefil and Summers try their best to keep the language geared to a lay audience, but they can't avoid some formulas: "Galileo's argument rests on the fact that the volume, and hence the mass, of a structure depends on the cube of its dimensions, while the size of the support area depends on the square." Overall, though, the prose is straightforward, and the authors make the potentialities of exoplanet life intriguingly real. Finally, they consider nonorganic life forms, for instance silicon chemistry replacing carbon-based life forms.

A curiosity-whetting investigation of imagined life beyond our world.

Kirkus Reviews