by Dave Brody
17 June 2005
from
Space Website
Dave Brody has been a Life Member of the National Space Society
since 1982.
He is currently IMAGINOVA's Executive Producer and
Director of Media;
the views expressed herein are entirely his own. |
This story first appeared in the Spring 2005 Issue of
Ad Astra
Magazine
"Men are weak now, and yet they transform the Earth's surface. In
millions of years their might will increase to the extent that they
will change the surface of the Earth, its oceans, the atmosphere,
and themselves. They will control the climate and the Solar System
just as they control the Earth. They will travel beyond the limits
of our planetary system; they will reach other Suns..."
Konstantin Tsiolkovsky
c.1926
Say the word "terraforming" amidst a gathering of space enthusiasts
and it's a bit like upending your beer mug in an Australian pub.
It
means you're ready to duke it out with anybody in the joint. And the
fight usually breaks out along these lines: One team sees the quest
to replicate the biosphere of Earth on other planets as a moral
imperative, an inevitable destiny, or both. Others - equally
passionate - recoil at such pretension, proclaiming with surety
that humans have no right to interfere with Nature as writ large
upon the face of other worlds. Both viewpoints are, of course, so
fraught with self-defeating conflicts as to be, well, flat out
wrong.
Weird, isn't it, that an enterprise that no one now alive can
remotely hope to see fulfilled should arouse such fire and fury?
[Nobody quibbles much about warp drives, wormholes or what we're
actually going to reply to ET.]
But there seems to be something
about the notion of taking a planet upon whose surface you did not
evolve and changing it to suit yourself that catalyzes all audiences
immediately to one pole or the other.
Bind yourself to the nearest mast and try to listen dispassionately
to the combatants and you'll start to hear these discussions for
what they really are: religious conflicts.
Disagreements rooted in
faith, belief and longing.
What you won't hear, usually, is good
science. Not often sound engineering tips. And not much of immediate
practical use to those of us who want to expand Humankind's range to
include the resource base of space, a primary goal of the membership
of the
National Space Society.
Equally odd, if you think about it, the terraforming tirades seem to
swirl solely around Mars.
The
asteroids are much easier to work
with. Earth's
Moon is closer, better known and sports a more
fun-friendly gravity field.
Europa, and (likely) other moons of the
gas giants, may have lots more liquid water and could harbor more
complex life. Comets have mega-tons of water and organics and they
visit us predictably.
And, as long as we're talking technology that
doesn't yet exist, we might imagine (as
Carl Sagan, and a generation
of science fiction writers before him, did) thinning and cooling the
atmosphere of Venus - a virtual twin of Earth in size and mass -
as least as easily as we could cause a thicker and warmer atmosphere
to magically stick to the low mass of Mars. [See Randa Milliron's
excellent article in the
winter 2005 issue of ad Astra.]
Yet Mars is where the terraforming battle rages now.
So let's face
it.
Designer Worlds
"Can we do it? We're doing it on the Earth," argues
Jim Bell, lead
scientist for the Mars Exploration Rovers' PANCAM, "We're changing
the Earth's atmosphere whether we realize it or not. It's certainly
within the realm of a reasonable extrapolation of future technology
to think we can do it on Mars. Must we do it? I don't think that's
our call. I think that's the call of the people who are living there
a hundred years from now, living in spacesuits, dealing with this
gritty dust that's all over the place, having to manufacture oxygen
from rock or ice underground."
Not everyone wants to wait that long:
"We have the capability now of
being the pioneer species that can go out to a currently barren
island out there on Mars and make it habitable for life," declares
engineer and author Robert Zubrin.
"Really, what humans are doing
is, in a sense, fulfilling an obligation on behalf of the
terrestrial biosphere."
Gaia Weighs In
There is a notion - strangely, embraced by both ultra-liberal tree
huggers and rabid reactionary exploiters - that the Earth is
somehow a self-regulating über-organism.
This idea implies that
Terra's vast mass and complex biosphere will adapt to human-induced
alteration in a manner that is ultimately favorable to that
biosphere as a whole system (though not necessarily good for
humans). But why would it be that Earth can do that, while Mars
seems to have "areo-formed" itself from a warm wet world to a cold,
dry barren wasteland?
As Jim Bell puts it:
"How do you go from an
Earth-like place, to a Mars-like place?"
That is a central question behind the current Spirit/Opportunity
missions.
And their Principal Investigator, Steve Sqyures, has this
to say about terraforming:
"We are very far from being able to
control - or even fully understand
- the climate of our own
planet. And I think that changing the climate of an entire planet in
an intended direction, getting an intended outcome and betting
people's lives on that outcome strikes me as a chancy proposition
for the foreseeable future. It sounds like a tough thing to do."
Perhaps this whole business may turn out to be about simply taking
control of the pace of biological change rather than about
redirecting towards or away from Earth's biology.
Astrogeophysicist Chris McKay, one of the first scientists to look
seriously into the notion of purposefully guiding the biological
evolution of Mars - and one of the founders of the so-called Mars
Underground - thinks of a Red Planet re-engineered, but for the
original residents.
"If there is life on Mars, it's not doing very
well. We know that from just looking at the planet. And it could use
some help," McKay believes.
"I think we would be ethically on good
grounds to support it, to encourage it to flourish into a global
scale biota like we have on Earth, especially if it was on the verge
of extinction which it could well be."
McKay would champion a technological effort to nurture these,
presumably microbial, or at least miniature, Martians:
"They would
have the right to evolve on their own biological trajectory.
Although Mars is a very interesting world without life, my own
personal judgment is that life is a more intrinsically valuable,
beautiful phenomena."
Chris McKay perceives a marked difference
between warming the planet up to support simple, stupid life and
fully engineering a human-shirtsleeve balanced Nitrogen/Oxygen
atmosphere at water cycling temperatures.
On McKay's Mars, the first
is possible and desirable; the second is not.
To do either requires giving the rusty red world a much thicker
atmosphere.
Mars atmospheric scientist Scot Rafkin isn't sanguine
about that possibility:
"I think it would be tough. And more than
the technical aspect, you have to wonder how expensive it would be
versus, say, enclosing huge regions of Mars and modifying the
environment for human habitation. It might make more sense to do
that than to try and add significantly more mass to the entire
atmosphere."
"Life on Mars probably died out young when the planet went through
this transformation to a thin, cold atmosphere," says planetary
scientist David Grinspoon.
"There's nothing about the ancient past
of Mars that was so different from Earth that the origin of life
should not have happened. I think it's quite reasonable to look for
fossils on Mars (but) in my opinion Mars at present is dead, dead,
dead."
Lacking any other examples of life in the Universe, there's no
denying that Earth life's propensity to begat more life is
spectacular.
"The fundamental policy of life is one of talking
barren environments and transforming them into those that are
friendly to the propagation of life," opines Mars Society founder
Robert Zubrin.
"That is why we have oxygen in Earth's atmosphere and
why there is soil on Earth's continents. It's an artifact of life.
Symbiotic communities of plants and animals have transformed the
Earth."
Earth life and
Mars
life could be rooted in the same DNA. Or they
could have had independent origins.
"The question of going to Mars
if there are, in fact, Martians - even microbes - is a question that
tends to be glossed over by people that are really excited about the
idea of going to Mars," David Grinspoon adds.
"The good news is that
there aren't Martians, I'm pretty sure. But we have to be a lot more
sure before we go starting to set up our strip malls and sports
stadiums."
Given our track record of modifying Earthly environments, can we
safely conclude that Nature has pre-destined - or at least
deputized - Homo sapiens to be the agent of its spread to the
stars?
Again, Bob Zubrin:
"Human beings in bringing life to Mars will be,
in a very real sense, continuing the work of Creation. We will not
be playing God but engaging in that activity that God gets the most
credit for doing.
By so doing, we will show the divine nature of the
human species and, therefore, the precious nature of every member of
it. No one will be able to look at a terraformed Mars and not be
prouder to be human."
Designer Humans
Ah, but what is a human in this brave new Universe?
Though the
specifics are fuzzy at best, no one disagrees that true, deep change
of an entire planet - Mars or any other - will take "a long time."
Our great-great grandchildren may find that it is easier to reshape
and supplement people to live on varied worlds than it is to rework
those worlds for the sake of people.
The bio-memetic revolution is
just now being born. And it may seem to its beneficiaries, a few
generations hence, that the idea of altering an entire globe to
perform like Earth is rather like Michelangelo depicting God as a
great white, corpulent, male, cloud-floating human. It's a great
work of art, but it now seems awfully exclusive and faintly
embarrassing.
Could be our concern here ought not to be for what our descendants
will think of us for having contemplated terraforming, but rather
what the terraformers' progeny will think of them for having
actually done it.
Heady stuff.
The Designer's Galaxy
One way to keep one's sanity inside a terraforming discussion is to
remember why one wanted to set sail for space in the first place.
Perhaps the most compelling reasoning for grabbing a toehold beyond
Earth was articulated by Greg Allison within these pages a few
months ago: survival, not just of we the "smart monkeys" but of
Earth's complex and explosive ecology.
"If you've got an endangered species, you don't want to have just
one little plot of it someplace,' says David Grinspoon.
"All life on
Earth is that endangered species. If we get to that stage where
we'll be moving from one celestial body to another, we'll have a
pretty good crack at outliving the Sun. We may be manning the
lifeboats, but in those lifeboats there will be all the species of
Earth coming with us (well, maybe not the mosquitoes)."
We space enthusiasts have felt this push for a long time.
Konstantin Tsiolkovsky, the Russian space visionary, began to build out a
sensible strategy for populating the galaxy while the Wrights were
still building bicycles. By the middle of the 1920's he "had it down
to a science" (engineering details to be worked out later, of
course).
A liberal translation goes like this:
-
Build, test and fly winged airplanes powered by rocket engines.
[Sound familiar, X PRIZE fans?]
-
Bit by bit, fly these faster and higher. [We now call it: "Build a
little; test a little"]
-
Drop the wings and create true rockets with reaction control
systems
-
Learn to splashdown from orbit into the cushioning ocean [Alan Shepard became Tsiolkovsky's test pilot in 1961]
-
Incrementally extend your
mission durations
-
Learn how to grow plants in
zero-G to make atmosphere
-
Get your crews comfortable
working outside in pressure-suits
-
Put your EVA skills to work
making closed-cycle orbiting plant nurseries
-
Build town-sized space stations
in various Earth orbits
-
Harness the Sun to heat your
habitats, nurture their plants and push your around the
Solar System
-
Expand your operation to the
Main Belt of asteroids, using their resources to replicate
your large habitats. Encourage big, diverse groups of people
to live there
-
Populate the rest of the Solar System
- and as much farther out
as you can get - changing planets as needed. [OK, so there's the
"T" word, finally]
-
Now - as a consequence of the god-like powers you've obtained
- work on changing humans to live more personally
fulfilling, socially responsible lives
-
Give in to population pressure
and expand Humanity's range to other stars; spreading
Earth's spawn geometrically
-
Leave the Sun behind entirely - sometime well before it burns
out.
So now you have it: a sixteen-step program to an infinite future for
the seed of Humankind.
Note how late in the game terraforming
appears. Almost a century ago, Tsiolkovsky's stunning intuition
showed that long before you get to the level of engineering required
to transform whole worlds, you already have everything you need to
prosper in space without such worlds!
And there are very good
reasons not to automatically gravitate to planets.
Planet Problems
Implicit in this notion of planned planetary engineering is that you
have to start with something the size of a whole world. But why do
that?
Students and followers of Gerard K. O'Neill (yes, this author is one
such) have conducted thousands of gentle, loving interventions for
the past three decades, trying to help our colleagues get past their
inborn "planetary chauvinism." Just because you evolved on a planet
does not necessitate that you continue to live on one.
And there are
some profoundly good reasons not to do so. Like that big honkin'
"gravity well" that you have to expensively and dangerously blast
your way up out of each time you need to go someplace. And the
bigger the planet, the worse the penalty.
It's tough to scale your engineering efforts to alter an existing
world, making it ecologically dynamic yet stable enough for biology
(like Earth's beneficial disequilibrium). But in building
ever-larger individual contained habitats, you may likely learn the
environmental and construction technologies to do so. Along the way,
you end up creating a whole host of custom-designed mini-worlds in
wide a range of shapes, sizes, climates, gravity levels and
life-styles associated with these factors.
Importantly, a widely distributed, de-centralized society is much
more resilient to (likely completely immune from) acts of senseless
terrorism - even if such acts are perpetrated on a planetary scale:
say a diverted retrograde comet; a doomsday bio-weapon; choose your
own personal nightmare...
And after all, planets are not common, not easy to travel to, and
not really all that nearby.
Enticing as it may be, Mars is still on the order of 100 million
miles away. And it's a bitch of an environment to work in: dusty,
cold, windy, dry... Much closer are the Near Earth Asteroids; easier
to get to than the Moon, much richer in materials too.
Planetary
geophysicist Dan Durda says it this way:
"By the time you pull all
the metals, the rich organic molecules, all the useful volatiles
like water, the oxides (for re-entry shields) out of the surface of
an asteroid, the slag (the garbage) you have left over has about the
same composition as the lunar soil."
And you, or your tele-operated
robot, can work your way around most any asteroid with your
fingertips.
There's no deep "gravity well" to climb out of.
Way to Go
Let's face it: space settlement - whether upon the surface of a terraformed sphere or within an engineered one
- is the living
embodiment of "disruptive technology."
If we go (and I say we must)
we will change the Solar System and it will change us.
Easy for writers, like yours truly, to sit back and poke irony; hard
to "put yer nickel down and bet". So I say this: Go on, inflame your
colleagues. Debate terraforming all you want. Challenge and duel to
your heart's content.
But at the end of the night - and
particularly the next morning when it comes time to approach the
bankers and the venture capitalists - let's do what works.
And what works is what takes the least work: Asteroid/comet
resources in near Earth orbits. The use of solar energy and
electro-tether technology - and a little bit of nuclear power - to
launch ourselves into a Hydrogen/Oxygen economy, which then would
drive higher-order materials processing.
And Humanity would get lots
and lots of cheap, free-floating, scalable, designer settlements in
interesting, useful orbits. Argue about modifying and colonizing
whatever mud-balls you want as soon as the technologies truly become
available.
But if you want to widely populate space soon, do this first.
The
way Tsiolkovsky, O'Neill and, perhaps, God (or at least the physics
of the Universe) intended.
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