Earths of Distant Suns : How We Find Them, Communicate with Them, and Maybe Even Travel There

Based on the latest missions results and supported by commissioned artwork, this book explores the possible lessons we may learn from exoplanets. As the number of known Earth-like objects grows significantly, the author explores what is known about the growing roster of "pale blue dots" far afield. Aided by an increased sensitivity of the existing observatories, recent discoveries by Keck, the Hubble Space Telescope, and Kepler are examined. These findings, once thought to be closer to the realm of science fiction, have fired the imaginations of the general public as well as scientists. All of us are mesmerized by the possibility of other Earth-like worlds out there. Author Michael Carroll asks the tough questions of what the expected gain is from identifying these Earth analogs spread across the Universe and the reasons for studying them. Potentially, they could teach us about our own climate and Solar System. Also explored are the more remote options of communication between or even travel to these distant yet perhaps not so dissimilar worlds.;Chapter One: A Place Like Home -- Chapter Two: Early Ideas and Lessons from Our Own Backyard -- Chapter Three: The Search for and Discovery of Exoplanets -- Chapter Four: Strange Solar System Architectures -- Chapter Five: Zeroing in on Earth 2.0 -- Chapter Six: Looking for Life in All the Right Places -- Chapter Seven: Could We Make Contact? -- Chapter Eight: Could We Visit Earths of Distant Suns? -- Chapter Nine: First Contact: What Will It Mean? -- Index. Acknowledgments 5 Contents 6 About the Author 10 1: A Place Like Home 11 The Nebular Theory of Planetary Formation 13 The Spiral Nebulae: Small and Close or Large and Distant? 14 Hello Out There 16 Homes for ET 18 Someone to Talk To 19 2: Early Ideas and Lessons from Our Own Backyard 21 Moving Off the Center 21 Getting the Message Across 24 The Goldilocks Principle 27 Migrating Habitable Zones 29 Starring Roles 30 M Dwarfs 32 K-Type Stars 33 G-Type Stars 33 F-Type Stars 34 A-Type Stars 34 B-Type Stars 35 O-Type Stars 35 From Supernova to Black Hole 35 Habitable Zone Types 36 Past Lives of Our Earth 38 The Great Dyings 42 Earthlike Planets in Our Solar System 42 Isn’t That Special? 46 A Really Big Habitable Zone? 49 Applying Lessons to Exo-Earths 49 3: The Search for and Discovery of Exoplanets 52 Finding Invisible Worlds 53 Direct Imaging 53 Radial Velocity 54 Timing Technique 56 Gravitational Microlensing 56 Autocorrelation Function Timescale Technique 58 Transits 58 Astrometry 61 The New Age of Discovery: Orbiting Observatories 64 51 Pegasi b...and Beyond 68 Chilled Giants 71 Earths, Mega-Earths, Sub-Neptunes and Super-Earths 72 4: Strange Solar System Architectures 76 Migrating Planets and the Search for Life 79 5: Zeroing in on Earth 2.0 83 Sub-Neptunes 83 Sea World: A New Kind of Planet 87 Giant Planets and Earth-Moons 90 Other Super-Earth Types 90 Assorted Super-Earths 93 What’s the Forecast? 97 Zeroing in on Earth 2.0 102 Super-Habitable Places 105 Giants Inside the Habitable Zone: The Promise of the Moons 111 6: Looking for Life in All the Right Places 113 Life Based on What? 113 Life in Our Own Image 113 A Martian Invasion of a Different Sort 115 Is Carbon the Only Game in Town? 122 Extreme Biomes 123 Under the Surface: Extremophiles Galore 124 Europa 126 Enceladus: Europa on Steroids 129 Titan: The Alien World Next Door 132 Habitable Sub-Zones 137 Deep Sea Astrobiology Beyond Europa and Enceladus 137 Life with a Few Suns 140 In the Beginning, Life 141 Life’s ‘Tells’ in the Poker Game of Astrobiology 144 Finding Exo-Veggies 148 The Stars Are Out, But Is Anyone Home? 149 7: Could We Make Contact? 152 Fermi’s Paradox 153 Answer #1: A “Special” Rare Earth 153 Answer #2: Extinction 154 Answer #3: Not Interested, Thank You! 154 Answer #4: We’ve Moved On 155 Answer #5: Sentient Suicide 155 Answer #6: Natural Quarantine 156 Answer #7: Cosmic Menagerie 156 Answer #8: Spectator Sport 157 Answer #9: Missed It By That Much 157 Using Waves 157 What Are the Odds? 159 Amoebas to Technology 164 Reaching Out 166 Transmission in a Bottle 171 Calls for Caution 175 Undertakings in the Search for Extraterrestrial Intelligence 176 A Different Kind of Message 180 If I Could Talk With the Animals... 183 Assumptions 187 UFOs 188 Civilization’s Fingerprints Here and Beyond 191 8: Could We Visit Earths of Distant Suns? 199 Interstellar Vacations 201 Roadblock to Faster-Than-Light Travel 204 Project Orion 206 Project Daedalus: To the Stars 208 Project Icarus 210 Non-Nuclear Options for Star Travel 212 Arrival 217 Interstellar Exploration’s Human Component 219 Generation Ships 221 Why Go? 223 9: First Contact: What Will It Mean? 225 Life’s Rich Pageantry 227 Visualizing World SETI 228 Why Bother? 230 SETI All Grown Up 231 Culture Clash 232 Dreams of Distant Earths 234 Engaging with the Others 234 Index 237 Front Matter....Pages i-xi A Place Like Home....Pages 1-10 Early Ideas and Lessons from Our Own Backyard....Pages 11-41 The Search for and Discovery of Exoplanets....Pages 43-66 Strange Solar System Architectures....Pages 67-73 Zeroing in on Earth 2.0....Pages 75-104 Looking for Life in All the Right Places....Pages 105-143 Could We Make Contact?....Pages 145-191 Could We Visit Earths of Distant Suns?....Pages 193-218 First Contact: What Will It Mean?....Pages 219-230 Back Matter....Pages 231-234