their Willow Spring Bed and Breakfast in Colorado’s magical San Luis
Valley. NASA and the National Science Foundation have generously
supported my research into comparative planetology. For keeping the
Funky Science office lurching along, I thank Holly Holloway, Tom
Arriola and, in particular, Antony Cooper for his unflappable calm,
competence, generosity, and creativity.
My brilliant and thoughtful agent Tina Bennett patiently guided me
through the entire book process, from proposal to publication. At
Ecco/HarperCollins I thank Dan Halpern, Julia Serebrinsky, and Gheña
Glijansky for invaluable advice, perseverance, and faith.
Most of all, I thank my wife Tory Read for her wit, charm, intelligence,
artistry, and soul, for reading through numerous drafts, providing skillful
editing, love, patience, and laughter, and for making whatever planet we
happen to be on the opposite of lonely.
David Grinspoon
Denver, Colorado
March 2003
P A R T I
Histor
History
Spirits from the Vasty Deep
1
We have all felt this impulse in our childhood as our
ancestors did before us, when they conjured goblins
and spirits from the vasty void, and if our energy
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continue we never cease to feel its force through life.
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We but exchange, as our years increase, the romance
of fiction for the more thrilling romance of fact.
—PERCIVAL LOWELL
I can call spirits from the vasty deep.
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Why, so can I, or so can any man, but will they come
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when you do call for them?
—SHAKESPEARE , Henry IV
P R O L O G U E : B R U I S E D B Y A N A L I E N
It was a dark and stormy night—and already a weird one. My friend
Damon and I trudged around through a snowstorm in the Meatpacking
District, hunting for a spoken-word/hip-hop/acid-jazz event someone had
said we had to see, while the wind whipped the streets into soft, majestic
canyons. We were ants lost in a liquid-filled snowy Manhattan, and some-
body up there was giving it a good shake. After hours of increasingly
blind and frozen searching, we ducked into a corner bar where a jazz
quartet was only slightly mangling Coltrane’s “Out of This World” and
sat down to regroup and have a drink. At one point we looked up at the
TV and there was Rudy Giuliani dancing with the Rockettes wearing fish-
net stockings and high heels. It was a little unsettling.
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L o n e l y P l a n e t s
Soon it was several drinks later, the band was finishing Miles Davis’s
“So What.” and our waitress was ready to end her shift. She leaned over
our table and asked just what we were blathering on about and what we
were doing in New York. We had been baiting each other—as we have
been doing since the eighth grade—into some twisted science fiction
scenario that seemed good at the time. Of course she was much more
impressed with Damon, who is both cuter and a film director, than
me, a scientist and a “writer” (yeah, right!). She started talking about
her acting experience and aspirations.* She was not obnoxious or pushy,
just friendly, and we welcomed the diversion. Eventually, perhaps just to
be polite, she asked me what kind of scientist I am. What I said was “I
study planets and I’m writing a book about aliens,” but what I was
thinking was “I wonder what her story will be.” And then she told us.
(Cue spooky, New Age music.)
drinks herself—she doesn’t remember how the night ended. There was
a strange interval of missing time, and she woke up the next morning
with an elaborate marking on her right outer thigh. It was a large,
stick-figure discoloration about six inches tall. It looked just like a
bruise, but it didn’t hurt like one. And just like a bruise, it faded. The
design appeared to show some sort of helmeted and antennaed space-
creature. I asked her if she could draw it for us, and she did, right there
on the back of our bar tab. She even signed it “Jillian.” Here it is:
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*This is how you know you’re not in Kansas anymore. In Denver the waiters are semi-employed musicians. Actors would be waiting tables in New York or L.A.
Spirits from the Vasty Deep
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Because you never know, I asked her permission to use the drawing
and the story in this book. She agreed without hesitation. She smiled
but didn’t seem to be putting us on. This clearly intelligent, articulate,
and apparently undisturbed woman was certain that she had had some
kind of alien encounter. Damon asked her if quaaludes were involved
but she swore that it was nothing like that.
Given the Giuliani vision, not to mention Jillian’s story, I would have
been inclined to think I had just hallucinated the entire evening, except
the next morning when I woke up, there it was. No markings on my
thighs, but a bar tab in my wallet with an alien on the back.*
One thing I’ve learned is that when it comes to aliens, everywhere
you go, somebody’s got a story. This actually solved a problem for me.
I already knew that I wanted to write about science and our beliefs
about aliens. To me, this is familiar territory. But how would I include
stories about UFOs, abductions, cattle mutilations, crop circles, and so
forth, the phenomena that are widely associated with the topic of
extraterrestrials everywhere except in the pages of scientific journals?
There are so many stories out there. It would be futile to try to be pro-
portionately representative, yet you’d have to be blind not to see that
aliens are all around us. Without really trying I’ve picked up my share
of alien paraphernalia: beach towels, glow pops, rolling papers, mag-
nets, a little green dancing statuette, and even a pipe-smoking-alien
lawn gnome. Much of this alien lore is tongue-in-cheek, but some not
entirely, and some leaves the tongue just hanging out there flapping
loose in the breeze. Fortunately, many on all sides of the UFO debates
approach the question with a proper dose of humor.
But what balance to strike? After all, dammit Jim, I’m a scientist, not
a comparative sociologist. Anything I have to say that is of any interest
to you, fair reader, is more likely from the perspective of a working sci-
entist, not a UFO dilettante.
Since it seems that virtually everyone has something to say on the sub-
ject, a strong belief, an opinion, or a must-read source of esoteric evi-
dence, I decided that rather than go to the aliens, I’d let them come to me.
After all, the cultural airwaves are saturated with alien signals, on all fre-
quencies, in all directions. All you need to do is unfurl your antennae, turn
*And they say that there are never identifiable artifacts left over from alien encounters.
Well, I still have it if anyone wants to run i
sotopic tests.
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on your signal analyzers, and let her rip. So, I thought, I’ll just pay atten-
tion to all of the transmissions passing through my little region of space.
It’s pretty hard to find someone who doesn’t believe in aliens,
although that can mean very different things to different people. Some
folks are convinced that NASA has photographed—and covered up—
elaborate cities on the surface of Mars. Others believe that little ET crea-
tures make nocturnal visits to the bedrooms of innocents, kidnapping
them, doing strange experiments, and then returning them to their beds
with important lessons for humanity. Legends of crash sites with alien
bodies and smashed saucers abound. The government has hidden and
dissected them, the story goes, in order to “reverse engineer” fantastic
energy and propulsion technologies that could set us all free, if only the
truth were released. On the other side of the rainbow, and closer to my
neck of the woods, are scientists, “astrobiologists,” who, through some
reverse engineering of our own evolution and biochemistry, have con-
vinced themselves that any life on other worlds must be just like ours.
These diverse beliefs are all modern responses to an ancient question.
T H E Q U E S T I O N
Hello?
Is anyone out there?
The question persists, ringing through the void like an electromag-
netic prayer. It may be innate—an instinct for self-discovery built into
the cosmos, a reflex reaction to conscious awareness, springing auto-
nomically to mind like air drawn into a lung.
The question goes way back. We’ve been wondering, speculating,
fretting, hallucinating, and prognosticating about aliens about as long
as anyone can remember. Strange creatures, variations on the human
theme, have always inhabited our fantasies and nightmares. Ever since
the lost, distant time when we became self-aware, waking slowly from
our ape dreams, pausing on some East African savanna to stare down
in amazement at our flexible fingers or up at the silent stars, we’ve had
the capacity and the inclination to wonder whether there were others
like us elsewhere.
Our ideas about where this “elsewhere” might be have evolved along
with our sense of where “here” is. There is an old, somewhat magical
sense of the term other worlds, where physical existence and location in space are irrelevant. These presumed realms of existence that somehow
Spirits from the Vasty Deep
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parallel or mirror ours have created infinite space for all manner of
imagined creatures not of this Earth. As we peer further back in time,
we see the fantastic off-world creatures permitted by modern science
morphing back into gods, angels, dragons, underworld demons, and
animal spirits.
To dream up modern, scientifically sanctioned extraterrestrials, we
first had to think of ourselves as terrestrials. We had to conceive of our
home planet as a limited part of a larger universe containing other sim-
ilar places. The Epicureans of ancient Greece started us down this road.
Their universe contained an infinite number of worlds, many of them
inhabited. Epicurus himself (341–270 B.C.) said, “We must believe that
in all worlds there are living creatures and plants and other things we
see in this world. . . .”
Did the Greeks mean what we mean by other worlds? Yes and no.
Their other worlds were not mere abstractions, they were actual physi-
cal places like Earth. But they had nothing to do with stars, planets, or
anything we observe in the sky. Indeed, the Greeks thought of the stars
as being not so far away, and the idea that the sun might be just
another star, if it occurred to anyone, must have seemed absurd. Their
other worlds were somewhere beyond the stars, too far away for us to
ever see. The history of ideas about extraterrestrial life is one of shifting
ground between physical and metaphysical realms. In this geography,
the other worlds of the Epicureans occupied an interesting middle
ground—places that were very real but forever concealed from us.*
The Epicureans reasoned that the sheer vastness of the cosmos made
all things, including other inhabited worlds, not only possible, but
inevitable. The Epicurean Metrodorus wrote, “To consider the Earth
the only populated world in infinite space is as absurd as to assert that
in an entire field sown with millet only one grain will grow.”
This idea, that a universe containing an infinite amount of stuff not
only allows but requires the existence of anything we can think of, is
often called the principle of plenitude. As I will show you, this principle has often reappeared in more modern guise.
Not all the Greeks agreed on this. Plato and Aristotle opposed the
Epicureans and argued against the existence of multiple worlds. Aristotle
had a scheme that explained the entire physical structure of the universe,
*Modern cosmology, with its “multiverse” containing infinite other universes that we can never observe, has returned us to a similar picture.
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but in the process ruled out other worlds. According to his doctrine of
“natural place,” everything is composed of the four elements earth, air,
fire, and water. Heavy stuff falls toward the center of the universe and
light stuff rises. All motions—rocks tumbling down a cliff face, leaves
blowing in a breeze, a billowing column of smoke, and water cascading
over a cataract—are explained by the settling of earth and water, and the
soaring of air and fire. This theory held sway in European thought for
over a millennium both because it worked pretty damn well and because
of Aristotle’s aura of untouchable authority. In fact, we have found much
of what Aristotle was groping for in our periodic table of the elements and
laws of gravity.
So what was Aristotle’s problem with other worlds? He didn’t think
of gravity as a force that draws every object toward all others.
Everything was pulled only toward the center of the Earth, which was
also the center of the universe. If any other worlds were out there, they
would come crashing down on our heads. Besides, how would these
worlds hold themselves together if their earth and water were drawn
not toward their own centers, but toward the center, down beneath our
feet? Aristotle also believed that the physical laws governing heaven
and Earth were fundamentally different. In this divided cosmos, every-
thing beyond the atmosphere was made of completely different matter
from all things terrestrial, so there could be no life like ours out there.
Both theories—Epicurean and Aristotelian—are elegant and logical,
but they lead to opposite conclusions about other worlds and extrater-
restrial life. This, in a nutshell, is the problem with philosophizing in
the absence of evidence. Without observations to ground our theories
in the real world, we can produce flawless arguments to reach any con-
clusion we want. Physical theories constructed without obser
vation,
however ingenious they may be, are ladders standing in quicksand.
Whether we’re really doing much better than this with our modern sci-
entific studies of life elsewhere, or perhaps just fooling ourselves into
thinking that we are, is one of the questions I’ll wrestle with in this
book.
O N T H E R E V O L U T I O N S
We couldn’t really worry about life on other planets before we realized
that we live on a planet, and for that we needed a revolution—the
Copernican revolution. That’s the name we give to the radical metamor-
Spirits from the Vasty Deep
9
phosis from a geocentric (Earth-centered) to a heliocentric (Sun-centered)
worldview. This shift in perspective was the first and hardest jolt in a
series of sudden awakenings to just how pint-size and peripheral we—
and our entire planet—are in the mind-numbing vastness of creation.
Except for a few historical oddities that never gained any following,
all models of the cosmos up into the sixteenth century placed the Earth
in the bull’s-eye at the center. That’s no surprise. If you simply believed
your eyes and your sense of balance, and you did not have the benefit
of modern astronomical observations, you would hold these truths to
be self-evident: that our world is immobile and the “dome of night” is
as it appears: a perfectly spherical realm in which all celestial bodies
travel in paths that circle us. Any theory that questioned this picture
challenged lifetimes of intuition and common sense.
Along came Nicolaus Copernicus, a visionary Polish astronomer who
advocated a Sun-centered cosmology mostly for aesthetic reasons—it
was a more pleasing design for the solar system. In his book De
Revolutionibus Orbium Coelestium (On the Revolutions of Heavenly
Orbs), he proposed that the Earth orbits the Sun along with the five
other visible planets.
It must have sounded crazy at first. Today we are brought up
immersed in a Copernican world. We learn as soon as we can under-
stand the words that the Sun appears to travel through the sky because
we stand upon a spinning Earth. We are continually exposed, through
catalog covers, movie posters, Web sites, and the evening news, to the
sight of our blue-and-white home planet spinning in space. Given this