Back | Next
Contents

A Pocket History of MacroEngineering: The First Millennium

Written by Gregory Benford
Illustrated by Adam Burch

193209300437.jpg

From the standpoint of a person in that distant past age around the year 2000, the central issues of the next thousand years would seem bizarre. But then, the previous millennium would have looked outrageous to either a king or a peasant peering forward from the year 1000. This Pocket History contains Historical Highlights, in a form intelligible to all forms of humans, even down to Traditional Classic Body Types of circa 2000.

The ebb and sway of political factions, and then of species-based opinion, should not obscure humanity's steady march. There was an ebb and sway to the human prospect, mostly about how much we should weigh upon our world. As the centuries rolled on from 2000 A.D., the multiplying human forms moved toward greater control of their environment. But they did not do this without constant voices that doubted the wisdom of it.

This has been a theme of our species since we separated from the chimpanzees some six million years ago:

* * *

2000-2150: The Earth Stewardship Era

In the latter half of the 21st Century the runaway greenhouse effect caught everyone's attention, especially after a billion died of the effects. This forced Green Puritans to consider planetary management. Warmed-over TwenCen objections to wise, planned human intervention faded as the true, already existing impact of human actions became obvious.

Humanity had been unthinkingly altering its world for millennia. Ice core samples showed that this began around 1000 B.C. with agriculture, which destroyed forests, released carbon dioxide and cut off the ice age that had kept humanity in poverty. To be sure, the early empires destroyed much of their rich lands. Northern Africa and what was once called the Fertile Crescent all became deserts. But the urge to make the world better, or at least distant, was strong. We were the breed of chimpanzee that restlessly moved over the horizon, after all, seeking fresh vistas.

Even so, resistance was strong. The Kyoto Accords of the early 21st Century had utterly failed to constrain the rising load of greenhouse gases. By 2060, amid storms and droughts that afflicted so many, the only argument was over whether thoughtful action was better than rash measures.

In any case, Stewardship soon became essential, following the several human diebacks in the tropical nations. Most of the oil was gone and replacement oil drawn from tar sands loomed as a mega-polluter. The planet needed cooling, fast.

Changes of cities' reflectivity eliminated their "heat island" effect, cutting air conditioning costs—simply by using white roofs and streets, and planting trees. The next Stewardship Stages stimulated cloud generation over tropical oceans, where reflected sunlight efficiency is highest. This went hand in hand with political necessity. The economic uplifting of poverty regions followed, and tropical manufacturing plants sent particle-rich plumes downwind, to grow clouds in daytime and fade at night.

Capturing carbon dioxide from the air, principally by depositing farm crop waste in the deep oceans, offset the fossil fuel burning of the developing nations. The crisis seemed to ebb.

Climate management became routine by 2140, but there was no rest for those weary of Stewardship. Other effects came into play, altering the planetary balance. Just as in the early 21st Century, early signs of a coming shift in climate—this time toward an ice age—met with disbelief. Radicals demanded new measures. Conservatives who profited from the current ideas opposed them.

Another long battle got fought out in the scientific community. Then government got involved, slowing down the debate. Yet another crisis loomed, the opposite of the last one. To avert this cooling trend and advancing glaciers meant reversing the solution—by spreading dark soil on polar caps. New atmospheric engineers suppressed the once billowy clouds in the tropics, letting those lands warm again.

The lesson was now clear. Earth had lurched first in one direction, then another. Human beings were the dominant ecological agent, like it or not.

Once taken up, guidance of the biosphere supporting 12 gigafolk could not be renounced, or else face the demise of whole societies. Geospheric Stewardship became the greatest moral imperative.

The Green Puritan movement was outlawed—but only for a while.

* * *

2200-2500: New Atmospheres on Two Worlds

Since Stewardship worked on Earth, why not afar?

As part of the general uplifting of humanity, we had begun gathering resources from beyond our moon. By 2100 metals had become harder to find in the Earth's crust, and more costly and damaging to extract. There were plenty of metals in the asteroid belt. Inevitably, we went to get them. Bringing them to Earth, smelting them in high orbits—all this helped fuel an expansion of the global economy.

But to support this industry demanded resupply of the Asteroid Anarchy from nearer that Earth—that is, from Mars. But working there was difficult, under a thin atmosphere and with little water.

Stewardship could apply there, as well.

* * *

The renegade Green Puritans tried to stage a revolt against the idea. The Red Mars Brigades used dire warnings and then terror to fend off the planetary engineers, but they were hopelessly outnumbered. Rocks, it turned out in the end, did not have rights.

Using the same dark soil deposition strategy on Mars melted the poles, releasing carbon dioxide and water. Discovery of Martian water reserves not too far beneath the red crust stimulated widespread pumping. These caused a quick greenhouse buildup in the thin atmosphere. That further melted some surface deposits, driving a slow accumulation of gases. Funded by the Fogg Foundation, this work continued until people could walk the surface wearing only pressure masks.

The Martian population spread across their arid lands, an area equal to the continents of Earth, with fresh vigor. They hunkered down each time a fresh, piloted comet came arcing in with new water. Robotic craft liberated these from the perpetual icebox of the far outer solar system. They fell down gravity's long gradient and came slamming into the upper Martian air, spreading moist wealth.

Good enough, but chilly Mars gets only half the sunlight of Earth. There is another spot at just the right distance from the sun, and near Earth, too. But with no air at all: the Moon.

For some time, lunar pioneers had been drilling their shelters. and uncovered deep ice beds. Venting of these made a thin atmosphere. Filmy clouds formed, the first in four billion years. This gave the pioneers an idea.

By that time the most valuable bulk commodity in the inner solar system had become light elements, gathered from cometary nuclei. The inner system is dry and at the bottom of a gravitational well, while at the top of the well, the outer system is wet with frozen ices. These swing in slow orbits between the vast cold bodies of Uranus, Neptune and Pluto. Slightly changing the velocity of an orbiting chunk of mostly ice and dirt could send it plunging down the well.

Harvesting such icebergs led to the "wild west" phase of water prospectors. For a small investment of velocity change, far "uphill" from the parched inner worlds, they could get rich. Their infalling rock and icebergs lit Earth's night skies with thousands of outgassing tails. Traders quickly sold these to development firms. Flown by their own gas pressures to landing sites, the dirty bergs dropped into the thin atmospheres of Mars and the Moon, blasting crater-basins. The new air of mostly water vapor changed quickly under the pelting of solar ultraviolet. Water gave hydrogen, which quickly escaped into space, leaving a growing bounty of oxygen. Add other active gases, released from the world's crust, and presto!—a new technology of atmosphere building.

193209300438.jpg

Martian entrepreneurs quickly blew bubble domes, using the rims of impact craters as starters. These domes got outfitted with soils and cultured with nanotech and bacteria. Moisture came to the red plains that had not known running streams for billions of years. Designer plants sprouted beneath skies that roiled with their own evolving clouds. Where the sky had been black and star-filled, ruddy sunsets spread.

Earthside, in the desert nations now drained of their oil, immigrants looked skyward. They were used to dry lands and had little prospect on Earth now. Islam found a new frontier. In the scarred craters recently blasted by comets, domes rose with mosques at their centers. Condominiums opened within 100 days of impact. Miners, manufacturers and even tourists bought them. They even had real estate agents.

On the Moon, hundreds of comet heads slammed into the ancient plains of dark lava. The atmosphere grew from the billowing splash and spray of massive icy chunks. To have an Earthly sea level atmospheric pressure demanded deep, brooding cloudbanks. Since the moon's gravity is a sixth of Earth's, its atmosphere had to be six times thicker. Contracts penalized anything that reduced atmospheric pressure. The low gravity meant that gasses blew off readily into space; that was how the primordial Moon lost its first atmosphere in ten thousand years.

Throughout these decades of furious work, debates rose again about megaengineering. For many the issues were hoary with age. Hadn't humans settled this? But such debates dug deep into the collective psyches of these recent smart primates. The issues would never truly be settled.

The Human Hubris Party urged their Precautionary Principle and won elections for a while, but only on Earth. Moonies disliked being told what to do by the Big Brother in their sky. Earth had oceans; why couldn't Luna have at least seas?

Soon, it did. The water-rich Lunar air quickly evolved, helped along by new kinds of plants that could thrive in the dry moon's gravel. Still, the atmosphere leaked away with distressing speed. They could not keep resupplying moisture from the dwindling store in the icebox of the outer solar system.

An entrepreneur solved this with a spherical Lunar Monolayer. This transparent skin was a millimeter thick and enveloped the whole world. Capping of the atmosphere trapped it, keeping the maverick hydrogen anchored. The heady, tropical lunar air steadied. The moon was now a beautiful sphere charming Earth's night sky, its low gravity beckoning to the retired. It was a whole world whose tropical belt extended all the way to the poles: an enormous Florida.

But how to get spacecraft through the Lunar Monolayer? Moonie Technologies found that part of the Monolayer could be made smart, able to iris open for a passing craft. Through these gate-gaps, ships bearing metals from the asteroid belt competed for passage rights with fat Earthside barges, packed thick with eager immigrants. The solar system had a Twin Planet paradise.

* * *

2345: The Supernova Catastrophe

Thanks to the Sentinel Astronomy program, humanity got an early warning that a brimming star 92 light years away soon was to go supernova. The news prompted a solar-system wide panic.

The bright flash of visible light was strikingly beautiful, leaving a glowing ember hanging in the sky for years. The slower high energy particles arrived just as most people were forgetting about the whole thing. This particle flood heated the upper atmosphere of all worlds as interstellar debris came hailing down through the atmospheres, changing their chemistry. On Earth, the Moon and Mars, the ozone layers evaporated away. The sun's ultraviolet poured down. Radiation levels climbed.

On Mars and Luna, people dug vast caverns that later turned into useful living space. In the asteroid belt, miners burrowed deeper into their rocky homes. Extensive measures to defend Earth's biosphere rushed ahead. The supernova flux heated the upper atmospheres for months. Spaceships stayed grounded. The fluxes brought the greatest accidental change ever seen in the atmospheres of Mars, Earth and Luna, performing in effect experiments no one would have approved. From scientific study of this, new Stewardship measures emerged. A disaster had turned into a bonanza of insight.

* * *

2600-2700: The Hydrogen Wall

Earth had spent several million years serenely gliding through the low density Local Bubble, a hot balloon in the interstellar gas blown by an ancient supernova. It was not to last, as our sun orbited in the galactic plane. Abruptly crossing this edge into a high density molecular cloud brought a sudden intrusion of interstellar hydrogen into the inner solar system. Neutral hydrogen loves oxygen, which it met in Earth's upper atmosphere. Marrying these atoms gave a burst of heat and birthed water. In turn the water condensed into thick clouds, cooling the planet. Oxygen levels dropped, leaving humanity gasping for breath.

Vast changes came. Mars. The entire asteroid complexes suffered great damage as well. Spacecraft hulls reacted with the drifting clouds of hydrogen, suffering gnawing erosion. This threatened imminent disruption of commerce with the outer solar system's water-rich provinces. The entire system could fail. Humanity had fathomed the atmospheres of worlds; now it has to learn of the particle and magnetic pressures throughout the solar volume.

This prompted the discovery that the electrodynamic forces of large magnetospheres, principally of the Sun and Jupiter, could be tuned to "short circuit" currents. Jupiter's moon Io was an enormous electrical generator, cutting across the Jovian magnetic field. Io orbits, Jupiter rotates, and the plasma between them conducts electricity very well along its magnetic field lines, which act as if they were wires connecting Io and the planet. Several million Amperes flowed there, and humanity's greatest engineering project stole the current away. The continuous current flow created a magnetic shield, feeding on Io's orbital energy.

Harnessed, the Jupiter-Io electromagnetic loop screened out much of the invading hydrogen by sucking it into an interplanetary dumpster. Megaengineers also used the energy to cleanse and mine valuable ices from the Jovian moons, while regulating hydrogen intrusion. This brought the flowering of magnetospheric engineering. A side benefit came from imposing signals on the currents, creating a powerful SETI signaling machine.

Similar capture of cosmic current loops brought protection to the Martian Free States and saved the Asteroid Anarchy. Plasma physicists became wealthy. The Electrodynamic Union became humanity's most powerful clan. Physicists were sexy again. They had wealth, power, fame, and could get dates.

* * *

2800-present: Solar Stewardship

The puzzling lack of neutrinos from the solar core had lingered, unexplained, for centuries. The sun was so hot at its center that furiously hot nuclei colliding there should shed neutrino storms, easily seen in experiments on Earth. But the observed flux was low. This seemed to say that the sun was running cooler than expected, deep down in the fiery furnace.

Then it did cool off. Sunlight ebbed. Plasma hurricanes and magnetic tornadoes peppered its face as a cooling front percolated to the surface. Winters deepened, snow stayed into May, and summers lost their warm charms. This finally forced a reexamination of theories of our sun's evolution. Sage Nobel laureates lost their jobs in embarrassment.

Young turks burrowed into the theory and soon showed that a major damping of the sun's interior fires lay ahead. Only intervention could avert disaster. Fresh from their Hydrogen Wall triumph, the Electrodynamic Union gurus fashioned a still larger project—a plasma donut.

Construction of a torus inside Mercury's orbit took a century of advanced plasma engineering. Activation of inductive currents in the torus produced a magnetic field centering on the solar core, the engine where nuclear processes were ebbing. Then they rippled the magnetic flux, creating a pump. Cyclic tuning of these fields drove surging circulation between the core and our star's outer shells. This brought differing masses into play, particularly fresh hydrogen.

These refreshed the solar furnace. The star ran hotter again. But a photon born at the core took a thousand years to work free, banging its way up through the layers under the surface. Humans couldn't wait that long.

So they pulsed the magnetic pump system harder still. Vast flows surged from core to surface, stirring a whole star. The sun's new magnetic heartbeat moved these furious energies to the surface. Warming of the corona appeared within months. Summer returned.

From there it was a short step to finer tuning, so that emissions could be directed at specific targets in the solar system. This allowed further warming of Mars, and of the cometary communities which had set up housekeeping in the inner solar system, greatly expanding the human prospect.

* * *

Whither the Species?

Interstellar travel now promises to extend the human habit of stewardship to the galaxy as a whole. The radical edge of the Mega engineering community advocates further experiments in the solar system. Against them the resurgent Puritan Enviros vehemently oppose tinkering with the planetary equilibria already struck. This much, they say, fine—but no more.

In particular, the recent proposal of a Day Without Sun—turning off sunlight as a laboratory experiment, to test new theories—faces widespread opposition. Perhaps here the Puritan Enviros are right. And yet . . . as a species, we have learned to walk by falling forward and then catching ourselves, turning a plunge into a stride.

As always, the boundaries of the human reach remain our most vexing moral problem.

Yet somehow, the human perimeter keeps increasing.

Perhaps that is the most enduring lesson.

* * *

Gregory Benford is the author of many novels and short stories, and has edited a number of anthologies.

Back | Next
Framed