Earth is the cradle of humanity, but one cannot live forever in a cradle.
-- Konstanin Tsiolkovsky.
We're all going to die..
Even if we stop all greenhouse emissions now, the sheer inertia of the planetary weather system will cause Earth’s average surface temperature to rise dramatically, according to the Intergovernmental Panel on Climate Change. It seems that the 21st Century is playing host to all four Horsemen, only they're wearing Armani and riding SUVs.
Maybe the increasing gradient won’t be a tipping point that’ll cause a runaway greenhouse effect ending in Earth becoming another Venus in a hundred million years or so. But it will cause rampant desertification, wholesale die-offs of sea life due to acidification, catastrophic rises in ocean levels, a supply crisis in potable water -- and that’s not in some dim and murky distant future; that’s in your lifetime, if you’re in your twenties. If you’re old enough to vote, you’re old enough to float.
(That high-pitched whine you hear is Thomas Malthus spinning in his grave -- though not fast enough, unfortunately, to provide the alternative energy we’ll need. And that dull thud was the world population hitting 7 billion as of Halloween, 2011 -- a date entirely too appropriate.)
Work with me here -- accept for a few moments that global climate change is a real, documented problem. All hope isn’t lost -- yet. But we have to profoundly change the way we look at the future, and the role that we play in it. We can no longer afford to think short-term.
We have to start thinking in terms of Deep Time.
Robert A. Heinlein once said: “Earth is too small a basket for mankind to keep all its eggs in.” Too true. Sooner or later we’re going to be pulverized by a killer asteroid, or fried by a supervolcano, or ... pick any one of a dozen potential apocalypses.
The big-rock-dropping-in-unannounced scenario is particularly unsettling, because it could happen any time from within the next 10,000 centuries to -- well, now. This isn't hyperbole. Consider, if you will, several bullet points (with the emphasis on "bullet"):
In 1990, an asteroid big enough to cause destruction comparable to Hiroshima's A-Bomb hit us. That's right. Hit. Us. It didn't make headlines because the impact was in the middle of the South Pacific, far enough from land that there was no tsunami effect. But a few hours either way would have had people talking. The ones that weren't busy ducking and covering, that is ...
The year before that, Asteroid 1989FC missed us by six hours. The rock, if it had hit in water (the most likely scenario, given that 70% of Earth is covered with ocean) would have caused a mega-tsunami; a wave at least 300 times as powerful as the 2004 Asian Tsunami. (For those of you heavily into irony, 1989FC is also known as Asclepius, the god of medicine and healing.)
But we were tracking it, right? Had it in our crosshairs? Dream on. We didn't have a clue. A bunch of techs looked at the plates later and said, "Wait, what?"
One more? Why not -- it’s not like there’s a dearth to choose from. How about 2009 DD45? Roughly the same size as the Tunguska impactor of 1908 that rendered a thousand square miles of forest flatter than a crop circle, it skimmed us closer than the tattooed swastika on a skinhead’s scalp.
Scared? You should be.
Bottom line: Earth is a big, slow target. And one thing we all learned from dodgeball is that it’s better to be small and light on your feet -- and, if you can manage it, in several places at once.
The best way to survive is to get some of us, at least, the hell out of Dodge. The problem is that leaving is far easier said than done. We’ve got two obstacles that are, by any reasonable definition, insurmountable.
The first is distance. The only world other than Earth that we’ve visited so far is the moon, and it’s the only one we’re likely to visit again anytime soon. That’s right; you might as well stuff any notions of reaching other star systems, including ones relatively "close by," back in your tinfoil-lined fedora, because even with the fastest rocket propulsion currently available, travel to the closest stars will still take millennia. Proxima Centauri, the next star over, is four and a half light years away, the interstellar equivalent of down the street and around the corner. Doesn't sound too bad -- until you remember that a light year is six trillion miles. Do the math on that one (hint: one trillion is one followed by twelve zeroes) and you'll get a vague inkling of the distances out there. Which means that some über-geek with coke-bottle glasses had better come up with warp drive in his parents’ basement soon, because there's no way we’re crossing the cosmos in first gear.
So let’s consider our satellite. While it’s close enough to make round trips semi-practical, it ain’t exactly a garden spot. Could we set up a permanent colony there? Frankly, I doubt it. We don’t have people living full-time and raising families at the South Pole, and it's Cancun compared to the moon. With temperature extremes that range over 500 degrees in a single step from sunlight to shade, an atmosphere less than one-trillionth that of Earth’s, and worst of all, an omnipresent and highly-toxic layer of pulverized meteorite dust that, once through the airlock and into your lungs, can cause pneumoconiosis faster than you can cough up blood, the moon doesn’t seem anybody’s first choice for prime extraterrestrial real estate.
But -- location, location, location, remember? The one thing we can count on is that the moon will always be about the same drive time. Which is a lot more than we can say about only other halfway habitable rock in the solar system: Mars.
That’s because while the moon is tucked away, nice and snug, in orbit around the Earth, Mars and Earth both orbit the sun -- and Mars’ orbit is a lot more eccentric. Mars can be anywhere from 36 million miles to over 250 million miles from us. In travel time that works out to anywhere from half a year to a year and a half, which makes booking rooms in advance a real bitch.
Trouble is, it’s the best alternative of all the other planets. Mercury? Like the moon, only hotter. Venus? Pretty to look at, but underneath those clouds it makes Hell seem hospitable.
Okay, how about the outer worlds -- Jupiter, Saturn, Uranus, Neptune? They’re not called “gas giants” out of sophomoric frat-house humor; there’s no “there” there, no hard and fast boundary between lithosphere and atmosphere. And let’s not bother mentioning Pluto; it’s not even officially a planet any more.
Even if there were some place in the Outer Planets that was halfway habitable, the gas giants and their moons are so far away that they might as well be in another solar system. Grad students have lost cherries and gained doctorates during the decade and more it's taking the New Horizons probe to reach Pluto. And that expedition is only feasible because the onboard robot has no need for life-support. There's no way we can afford to send crewed exploratory flights on a three billion mile schlep. The amount of food and fuel alone needed makes it impossible to get a manned mission of that complexity off the ground. Not to mention water. It’s true that recycling from sources best left unnamed can maximize usage, but eventually the stores have to be replenished. While there is water on the moon, there isn’t enough to warrant establishing a full-time colony. Mars, on the other hand, has plenty of subsurface water, but again, the ratio of H2O to the energy required to land and dig for it is problematic.
So it looks like, for all its considerable drawbacks -- temperatures that only look good compared to the moon, the lack of a magnetosphere which makes a tan deadly, and a travel time about twice as long as sailing around Cape Horn (along with enough cosmic rays to give the entire population of Detroit superpowers) -- Mars is the best place.
Except ... remember I said two obstacles?
Space is big -- there’s no getting around that. But as staggeringly
complex as merely getting to another world is, there’s a much greater problem once we’re there. One which makes cosmic rays, temperature extremes and lack of atmosphere look easy. We can overcome these problems, at least in theory, with terraforming techniques. It would require engineering on a cosmic scale -- playing planetary billiards with icy comets to create oceans, putting orbital mirrors up to magnify sunlight, using hydroponics to “grow” oxygen and nitrogen. Given decades of global restructuring, Mars could be tricked out with a breathable atmosphere, a decent climate -- everything except one essential thing:
Gravity. That’s the one thing we can’t increase or decrease, since it’s a function of mass. Mars is one-third the size of the earth, and has (more or less) one-third as much gravity. The moon has one-sixth. And we won’t be changing either one any time in the near future. So, unless we're lucky enough to find another world tucked away somewhere close by whose gravitational pull is within 10 to 20 percent, plus or minus, of Earth's, we're screwed.
The problem is that, no matter how many technological advances we make, genetically we’re still just a bunch of hairless apes jabbing each other with pointed sticks on the African veldt. We evolved in a one gravity field, and when we spend prolonged periods out of it (such as a few months up in the space station), bad things happen.
Prolonged weightlessness causes, among other things, dehydration, musculoskeletal atrophy, anemia, mineral and electrolyte depletion, vertigo, and a whole host of other problems ranging from unpleasant to downright life-threatening. Back in the “Pulp Era” of science fiction, when space flight was still a testosterone-fueled dream, it was theorized that time spent in zero-gee would actually be good for the body. No stress on the joints or the heart would logically mean no wear and tear on other moving parts; ergo you might outlive Methuselah and remain as spry as Barishnakov.
Unfortunately, like so many rose-colored visions of The Future everyone had back then, pretty much the opposite holds true. Long-term weightlessness resembles, in syndrome, accelerated aging. Spend a couple of years in space (the average time of a trip to Mars), and you wind up looking -- and feeling -- like your grandfather. Sure, the process can be slowed somewhat -- by near-constant workouts. I don’t know about you, but riding an Exercycle all the way to the Red Planet and back isn’t a trip I’m particularly looking forward to.
And we haven’t even discussed the physical and psychological effects (about which, admittedly, we don’t know much yet, but the probabilities aren’t looking good) of carrying a child to term and raising him or her in a lighter gravitational field. How will nine months in a womb on Mars affect bone structure? Muscle development? Brain growth? God knows.
And on top of all that, the latest findings indicate quite strongly that combined solar and galactic high-energy cosmic rays, zapping through the inner and outer planets with a reckless abandon that would make a Bangladeshi traffic cop's jaw hit the asphalt like Wile E. Coyote's, are several orders of magnitude more dangerous than previously expected. So, in addition to the dangers already listed in our Martian Odyssey, we can add making the trip in what is essentially an enormous microwave oven.
Doesn’t look good, does it? Earth’s on a fast track to disaster, the only other worlds we have even the faintest chance of reaching aren’t even remotely pleasant, and just getting there can kill us. And there’s no other world within practical reach -- certainly not in the next century or so, which everybody with a PhD is telling us is longer than we’ve got left here.
So what can we do?.
We can make a world.
Gravity is far and away the weakest force in the universe. Hard to believe, but the electromagnetic energy contained in a refrigerator magnet weighing a quarter of an ounce is more than sufficient to overcome the gravitational energy of the entire Earth -- which weighs, in case you're interested, 6,000,000,000,000,000,000,000 (six septillion) metric tons, give or take a few million. (Actually, the Earth doesn't technically weigh anything, since it's in a state of constant free fall around the sun, but let's face it; all those zeroes are pretty durn impressive.).
But while gravity is weak, it’s also pervasive. Although it decreases with distance, it never really fades completely. The upshot being that the gravitational forces from the sun, the moon, Earth and the other planets all interact, creating whorls and eddies in spacetime like colliding river currents in a placid lake.
These result in stable spots at certain locations, called LaGrange Points: areas of space where the orbital motions of bodies balance with their gravitational forces. There are five of them in the Earth-Moon system alone, and the L-4 and L-5 points are so stable that large objects plunked down in the middle of them will stay there, without course corrections, for a long, long time.
Gravity’s not a problem either. If you’re living on the inside of a cylinder instead of on the surface of a planet, it’s easy (well, easier) to create "artificial gravity" by simply spinning the cylinder. Centrifugal Force pushes everything against the inner surface of the torus, just like in those old Tilt-A-Whirl rides at the carnival. It isn't a force in the classical sense; merely a moving body's resistance to a change in inertia. But who cares? The point is that the effect is indistinguishable from gravity. And if the cylinder’s big enough, the inner-ear effect will be diluted, so you won’t constantly feel like throwing up everything you’ve eaten since you were five. (There's also an impressive variety of antiemetic drugs available OTC to settle that queasy tummy.) .
What’s more, the LaGrange Points aren’t just confined to the Earth-Moon system -- there are points of stability everywhere that planets and moons do their complex orbital dances. Colonies built at these libration points are the only viable way of leaving Earth behind. Controlled environments, with regulated day and night cycles and normal “gravity,” free from natural disasters and presenting much smaller, faster-moving targets for giant impactors, make a helluva lot more sense than trying to hardscrabble a living on the moon or Mars. While it is possible to build "gravity wheels" -- essentially enormous underground centrifuges to take up the inertial slack on the moon and Mars, it would probably take as long, and in the case of Mars at least, cost as much or more to build them than it would to build the habitats, once you factor in the extra distance and the mining of raw materials. It's cheaper and easier to use metals and ores from near-Earth asteroids that are "low-hanging fruit" and take advantage of the much finer production quality of zero-gee metallurgy, not to mention the vastly shorter commute. Besides, the quality of life possible in a habitat is limited only by architectural imagination, whereas once you've finished construction of a base on Mars, for example, you still have to deal with problems ranging from the niggling, such as that extra forty minutes in each Martian day, to the life-threatening planetary dust storms. Not to mention It -- the Terror From Beyond Space.
I trust I've made my point...
And eventually, once we settle in all nice and comfy, we can build smaller, sleeker craft with solar sails or other passive propulsion devices that'll take our descendants to the Centauri system, or Barnard's Star, or other "local" systems. Long before then we'll have space-based telescopes powerful enough to ascertain which stars have Earth-like worlds -- although our heirs will, in all probability, think it insane to leave our comfortable climate-controlled habitats to return to the chaos of a planetary environment. After all, would you seriously consider abandoning the air-conditioned environment of your condo for a damp and dank cave?
In August of 1962, President John F. Kennedy asked rhetorically, Why choose to go to the moon? "We choose to go to the moon," he said, "in this decade and do the other things, not because they are easy, but because they are hard. Because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win."
With those words, the thirty-fifth President sounded a clarion call that defined the Sixties for many as much or more than the war in Viet Nam, the music of the Doors, or the art of R. Crumb. It sparked the beginning of a decade-long, across-the-boards effort that united scientists, teachers, engineers, doctors, test pilots (the last group under the new rubric of "astronauts") and many others in a single goal -- to win the Cold War by beating the godless Commies to the moon. Because make no mistake; we needed a foe, a mysterious and implacable enemy, to rally the troops so that, on that glorious day in July 1969, we could stand proud as a nation on the dusty gray plain of Mare Tranquilatis and say to the Soviets in a voice strong and united: "Neener-neener-neener!"
Many felt that America’s military, engineering and scientific communities have never been as unified regarding anything as we were behind the space program during those ten years -- despite the generation gap, burning bras and draft cards, and a distressing tendency on the part of circuit court judges to throw beardless youths into hardcore maximum security for a few decades just for possession of a single Jamaican Red joint. (On the other hand, it was Christmas all year long for inmates named Bubba and Cletus.)
To reach the moon, we crammed fifty years of technological development into a single decade. It won’t be as easy this time. This time our foe can’t be found in the gray monolithic hallways of the Kremlin or the Forbidden City. This time, as Walt Kelly’s Pogo said, “We have met the enemy and he is us.”
Which brings us back to Deep Time.
Instead of going for the quick fix, the (relatively) easy gratification, we’ll have to adopt a mindset that we as a species haven’t used for centuries: patience. We have to look back in order to move forward; back to the times when we routinely embarked on projects so monumental they took generations to finish. Projects like the cathedrals of Europe, the pyramids of Egypt, the aqueducts of Rome; projects of which the builders knew they would never see the completion; the trade-off was lifetime room and board (if not necessarily pay).
It was easier for people who lived back then to accept that one’s father and one’s son would be employed on the same venture, because back then the future looked much like the past. Change was slow and incremental; we hadn’t reached the steep part of the curve yet, whereas today we’ve toiled up and over the top and are now in free-fall. Think of the world a hundred years ago: the majority of the population had never even heard the sound of an internal combustion engine nor seen an airplane, much less ridden in one. Most lived and died within fifty miles of their birthplace. The world’s population was just over a billion and a half, and life expectancy for adults in America around fifty. Since then, there have been more changes -- technologically, biologically, sociologically, and in any other venue you can name -- in the 20th Century than in all of human history.
And as for the 21st Century:
"We set sail on this new sea because there is new knowledge to be gained, and new rights to be won, and they must be won and used for the progress of all people."
The stakes are far higher than Kennedy knew; far, far higher than few today will admit. Because what's at stake now isn't just progress -- it's survival. If humanity is going to make it, it won't be here on planet Earth. It'll be out there: outside the atmosphere, beyond the van Allen Belts, across the frothing sea of radiation and cosmic dust.
And the diaspora will be soon. How do I know this?
Because if it isn't accomplished soon, humanity is done.
But we don't have to be. We have most of the technology we need -- in fact, we are far more equipped and prepared to create the L-5 habitats with our current level of knowledge and ability than we were capable of landing a man on the moon a decade prior to Neil Armstrong's one small step.
It's our choice. Oh, sure, we can wait for the aliens to come, arriving against a background of theremin music and a strobing light show, and just give us the tech we need. But the chances of it happening from star-folk sporting heads the size of casaba melons and Seventies-style silver lamé jumpsuits? Put it this way:
In 1950, the physicist Enrico Fermi ruined everyone's lunch by asking one of the most troublesome rhetorical questions in astrophysics: "Where is everybody?"
The Fermi Paradox, as it came to be known, is simply stated: it cites the apparent contradiction between the high probability of extraterrestrial civilizations' existence and the lack of contact with them. According to the Drake Equation, it seems probable that many extra-terrestrial civilizations are ephemeral; if they form at all, they don't last very long. And that's the problem. Despite the unimaginable distances between the stars, what isolates us isn't space so much as time. Consider: Homo sapiens has only been around for a half million years, and we've only been broadcasting our presence for a hundred or so. And, after a brief spike in the 50s and 60s, our radio wave transmissions have fallen off sharply in recent years, because everyone's gotten cable. (Yeah, that's right; the chances of E.T. phoning us have dropped drastically because you had to have HBO.) Pop quiz: given the billions of years it takes life to develop on worlds such as Earth, what are the odds of some aliens just happening to intercept a Jerry Lewis telethon on their interstellar iPhone by listening in at precisely the right cosmic moment?
Your answer counts for half your grade.
The paradox of the Great Silence has only grown more salient with the discovery in the last decade of a huge bevy of exoplanets. With literally billions of earth-like worlds estimated in our galaxy alone, the chances are overwhelming that life must have developed on a significant portion of them, and intelligent life (if we define "intelligence" as the ability to imagine and eventually search for other civilizations) on at least a few. If no more than one other civilization made it further than we have, they could have seeded the entire galaxy with robot probes in a few million years. That sounds like a long stretch, but in terms of Deep Time, it's really not. The Milky Way is over ten billion years old; almost as old as the universe itself. A million years -- a million centuries -- is nothing.
Once SETI put its collective ear to the sky back in the early Sixties, we had every expectation of hearing radio waves from Out There buzzing, humming, stridulating and otherwise vocalizing juicy galactic gossip. Instead we got the lonesome interstellar equivalent of crickets chirping.
But -- even considering the few brief sparks of civilizations guttering in the vast cosmic night, such a plenitude of Earth-like worlds postulated still begs Fermi's question: Where is everybody?
There are a few hypotheses as to where everybody's hiding -- my favorite is the Prime Directive, AKA the Zoo Hypothesis, which should be self-explanatory even to non-Trekkies. But there's also a more sinister one, known as the Great Filter. It says that the majority of civilizations reach a point at which they either run out of energy and catastrophically return to barbarism, or make it past the crisis and enter a technological utopia.
Judging from the signal-to-noise ratio out there, it would seem that utopia is seldom achieved.
But "seldom" isn't the same as "never." I think that, if we want to join the galactic Kiwanis, we'll have to take the initiative.
We have to get the hell out of Dodge.
Imagine a future a hundred years from now: a huge factory station, one of dozens set in orbit high above an uninhabited world, where robot miners feed a constant supply of raw materials via space elevators up to us, to be fabricated into whatever we desire. It's certainly a pleasant vision of the centuries to come -- far more so than endless variations of Little House On Utopia Planitia. And we'll have the luxury of time to decide if it's for us or not. Time and space, and plenty of both.
All of eternity and infinity.
Mankind has searched for a way to secure passage into Heaven (without the inconvenient proviso of having to die first), for as long as he's walked upright. Prayer hasn't proven overly efficacious -- neither has abstemiousness, sacrifices or genocide. But now, finally, we have the tools; if we have the will and the fortitude as well, we can build Heaven.
It’s that, or take our chances on an Earth that’s all too rapidly going to Hell.
(c) By Michael Reaves
All Rights Reserved