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

240 Pages·2017·11.01 MB·English

by  Carroll, Michael

Michael Carroll
Earths of
Distant Suns
How We Find Them,
Communicate with Them,
and Maybe Even Travel There
Earths of Distant Suns
Michael   Carroll
Earths of Distant Suns
How We Find Them, Communicate with Them,
and Maybe Even Travel There
Michael   Carroll
Fellow, International Association of Astronomical Artists
Littleton , CO , USA
ISBN 978-3-319-43963-1 ISBN 978-3-319-43964-8 (eBook)
DOI 10.1007/978-3-319-43964-8
Library of Congress Control Number: 2016951720
© Springer International Publishing Switzerland 2017
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Acknowledgments
My thanks to Babak Tafreshi, talented astrophotographer, for the lovely view
of the ALMA telescope. Babak, you let us hear the heavens sing! Nick Stevens
played a key part in my understanding of interstellar ships and nuclear pulse
propulsion. As if that weren’t enough, he shared his artistic masterpieces for
the book! Steve Walker and Dorian Houser of the National Marine Mammal
Foundation put up with my wacky questions with good humor. So did my
buddy, “dolphin whisperer” Alan Lewis, who got them into it in the fi rst place.
Th anks, Alan! Adrian Brown and Matthew Tiscareno played instrumental roles
in my visit to SETI, as Chris McKay and Elisa Quintana did for my tour in
NASA/Ames’ astrobiology wonderland. (Th anks for your offi ce, Chris!) Special
commendation in the “Twilight Zone” category goes to premiere science writer
Tina Saey, who made the same bizarre Star Trek/silicon life connection I did.
Her article for S cience News came out the week after I submitted this manu-
script to my line editor. Good thinking, Tina! Th e fi rst reader and line/content
editor extraordinaire Marilyn Flynn lent her magic. Finally, my gratitude to
Caroline, who not only organized this literary mess but always lends structure
and meaningful organization to my own wacky life. Love you, sweetie!
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Contents
1 A Place Like Home 1
Th e Nebular Th eory of Planetary Formation 3
Th e Spiral Nebulae: Small and Close or Large and Distant? 4
Hello Out Th ere 6
Homes for ET 8
Someone to Talk To 9
2 Early Ideas and Lessons from Our Own Backyard 11
Moving Off the Center 11
Getting the Message Across 14
Th e Goldilocks Principle 17
Migrating Habitable Zones 19
Starring Roles 20
M Dwarfs 22
K-Type Stars 23
G-Type Stars 23
F-Type Stars 24
A-Type Stars 24
B-Type Stars 25
O-Type Stars 25
From Supernova to Black Holes 25
Habitable Zone Types 26
Past Lives of Our Earth 28
Th e Great Dyings 32
Earthlike Planets in Our Solar System 32
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viii Contents
Isn’t Th at Special? 36
A Really Big Habitable Zone? 39
Applying Lessons to Exo-Earths 39
3 Th e Search for and Discovery of Exoplanets 43
Finding Invisible Worlds 44
Direct Imaging 44
Radial Velocity 45
Timing Technique 47
Gravitational Microlensing 47
Autocorrelation Function Timescale Technique 49
Transits 49
Astrometry 52
Th e New Age of Discovery: Orbiting Observatories 55
51 Pegasi b…and Beyond 59
Chilled Giants 62
Earths, Mega-Earths, Sub-Neptunes and Super-Earths 63
4 Strange Solar System Architectures 67
Migrating Planets and the Search for Life 70
5 Zeroing in on Earth 2.0 75
Sub-Neptunes 75
Giant Planets and Earth-Moons 82
Other Super-Earth Types 82
Assorted Super-Earths 85
What’s the Forecast? 89
Zeroing in on Earth 2.0 94
Super-Habitable Places 97
Giants Inside the Habitable Zone: Th e Promise of the Moons 103
6 Looking for Life in All the Right Places 105
Life Based on What? 105
Life in Our Own Image 105
A Martian Invasion of a Diff erent Sort 107
Is Carbon the Only Game in Town? 114
Extreme Biomes 115
Under the Surface: Extremophiles Galore 116
Contents ix
Europa 118
Enceladus: Europa on Steroids 121
Titan: Th e Alien World Next Door 124
Habitable Sub-Zones 129
Deep Sea Astrobiology Beyond Europa and Enceladus 129
Life with a Few Suns 132
In the Beginning, Life 133
Life’s ‘Tells’ in the Poker Game of Astrobiology 136
Finding Exo-Veggies 140
Th e Stars Are Out, But Is Anyone Home? 141
7 Could We Make Contact? 145
Fermi’s Paradox 146
Answer #1: A “Special” Rare Earth 146
Answer #2: Extinction 147
Answer #3: Not Interested, Th ank You! 147
Answer #4: We’ve Moved On 148
Answer #5: Sentient Suicide 148
Answer #6: Natural Quarantine 149
Answer #7: Cosmic Menagerie 149
Answer #8: Spectator Sport 150
Answer #9: Missed It By Th at Much 150
Using Waves 150
What Are the Odds? 152
Amoebas to Technology 157
Reaching Out 159
Transmission in a Bottle 164
Calls for Caution 168
Undertakings in the Search for Extraterrestrial Intelligence 169
A Diff erent Kind of Message 173
If I Could Talk With the Animals… 176
Assumptions 180
UFOs 181
Civilization’s Fingerprints Here and Beyond 184
8 Could We Visit Earths of Distant Suns? 193
Interstellar Vacations 195
Roadblock to Faster-Th an-Light Travel 198
Project Orion 200
x Contents
Project Daedalus: To the Stars 202
Project Icarus 204
Non-Nuclear Options for Star Travel 206
Arrival 211
Interstellar Exploration’s Human Component 213
Generation Ships 215
Why Go? 217
9 First Contact: What Will It Mean? 219
Life’s Rich Pageantry 221
Visualizing World SETI 222
Why Bother? 224
SETI All Grown Up 225
Culture Clash 226
Dreams of Distant Earths 228
Engaging with the Others 228
Index 231
About the Author
A uthor/artist Michael Carroll has spent decades as a science journalist and
even longer as an astronomical artist. He received the AAS Division of
Planetary Science’s Jonathan Eberhart Award for the best planetary science
feature article of 2012. He lectures extensively in concert with his various
books and has done invited talks at science museums, aerospace facilities,
and NASA centers. He has written articles and books on topics ranging from
space to archeology. His articles and art have appeared in T IME , N ational
Geographic , S cientifi c American , Smithsonian , Popular Science , Astronomy , Sky
and Telescope , A stronomy Now (UK) , and a host of children’s books and mag-
azines. Among his twenty-some books are Springer’s Living Among Giants:
Exploring and Settling the Outer Solar System and his novel On the Shores of
Titan’s Farthest Sea for Springer’s Science and Fiction series (2015). One of
his paintings is on the surface of Mars—in digital form—aboard the Phoenix
lander. Carroll is the 2006 recipient of the Lucien Rudaux Award for lifetime
achievement in the astronomical arts. He is a fellow and founding member of
the International Association of Astronomical Artists.
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