Green Mars. Kim Stanley Robinson

overlapping, and then the bundles were bundled, until the cable was nine metres in diameter. The factories could create the filaments and bundle them at speeds that allowed them to extrude the cable at a rate of about four hundred metres an hour, ten kilometres a day, for hour after hour, day after day, year after year.

       While this thin strand of bundled carbon spun out into space, robots on another facet of the asteroid were constructing a mass driver, an engine that would use the deuterium from the indigenous water to fire crushed rock away from the asteroid at speeds of two hundred kilometres a second. Around the asteroid smaller engines and conventional rockets were also being constructed and stocked with fuels, waiting for the time when they would fire, and perform the work of attitude jets. Other factories constructed long-wheeled vehicles capable of running back and forth on the growing cable, and as the cable continued to appear out of the planet, small rocket jets and other machinery were attached to it.

       The mass driver fired. The asteroid began to move into a new orbit.

       Years passed. The asteroid’s new orbit intersected the orbit of Mars such that the asteroid came within ten thousand kilometres of Mars, and the collection of rockets on the asteroid fired in a way that allowed the gravity of Mars to capture it, in an orbit at first highly elliptical. The jets continued to fire off and on, regularising the orbit. The cable continued to extrude. More years passed.

       A little over a decade after the landers had first touched down, the cable was approximately thirty thousand kilometres long. The asteroid’s mass was about eight billion tons, the cable’s mass was about seven billion. The asteroid was in an elliptical orbit with a periapsis of around fifty thousand kilometres. But now all the rockets and mass drivers on both New Clarke and the cable itself began to fire, some continuously but most in spurts. One of the most powerful computers ever made sat in one of the payload bays, co-ordinating the data from sensors and determining which rockets should fire when. The cable, at this time pointing away from Mars, began to swing around toward it, as in the pivoting of some delicate part of a timepiece. The asteroid’s orbit became smaller and more regular.

      More rockets landed on New Clarke for the first time since that first touchdown, and robots in them began the construction of a spaceport. The tip of the cable began to descend toward Mars. Here the calculus employed by the computer soared off into an almost metaphysical complexity, and the gravitational dance of asteroid and cable with the planet became ever more precise, moving to a music that was in a permanent ritard, so that as the great cable grew closer to its proper position, its movements became slower and slower. If anyone had been able to see the full extent of this spectacle, it might have seemed like some spectacular physical demonstration of Zeno’s paradox, in which the racer gets closer to the finish line by halving distances … but no one ever saw the full spectacle, for no witnesses had the senses necessary. Proportionally the cable was far thinner than a human hair—if it had been reduced to a hair’s diameter, it would still have been hundreds of kilometres long—and so it was only visible for short portions of its entire length. Perhaps one might say that the computer guiding it in had the fullest sensation of it. For observers down on the surface of Mars, in the town of Sheffield, on the volcano Pavonis Mons (Peacock Mountain), the cable made its first appearance as a very small rocket descending with a very thin leader line attached to it; something like a bright lure and a thin fishing line, being trawled by some gods in the next universe up. From this ocean bottom perspective the cable itself followed its leader line down into the massive concrete bunker east of Sheffield with an aching slowness, until most humans simply stopped paying attention to the vertical black stroke in the upper atmosphere.

       But the day came when the bottom of the cable, firing jets to hold its position in the gusty winds, dropped down into the hole in the roof of the concrete bunker, and settled into its collar. Now the cable below the areosynchronous point was being pulled down by Mars’s gravity; the part above the areosynchronous point was trying to follow New Clarke in centrifugal flight away from the planet; and the carbon filaments of the cable held the tension, and the whole apparatus rotated at the same speed as the planet, standing above Pavonis Mons in an oscillating vibration which allowed it to dodge Deimos, controlled still by the computer on New Clarke, and the long battery of rockets deployed on the carbon strand.

       The elevator was back. Cars were lifted up one side of the cable from Pavonis, and other cars were let down from New Clarke, providing a counterweight so that the energy needed for both operations was greatly lessened. Spaceships made their approach to the New Clarke spaceport, and when they left they were given a slingshot departure. Mars’s gravity well was therefore substantially mitigated, and all its human intercourse with Earth and the rest of the solar system made less expensive. It was as if an umbilical cord had been retied.

      

      He was in the middle of a perfectly ordinary life when they drafted him and sent him to Mars.

      The summons came in the form of a fax which appeared out of his phone, in the apartment Art Randolph had rented just the month before, after he and his wife had decided on a trial separation. The fax was brief: Dear Arthur Randolph: William Fort invites you to attend a private seminar. A plane will leave San Francisco airport at 9 a.m., February 22nd 2101.

      Art stared at the paper in amazement. William Fort was the founder of Praxis, the transnational that had acquired Art’s company some years before. Fort was very old, and now his position in the transnat was said to be some kind of semi-retired emeritus thing. But he still held private seminars, which were notorious although there was very little hard information about them. It was said that he invited people from all subsidiaries of the transnat; that they gathered in San Francisco, and were flown away by private jet to somewhere secret. No one knew what went on there. People who attended were usually transferred afterward, and if not, they kept their mouths shut in a way that gave one pause. So it was a mystery.

      Art was surprised to be invited, apprehensive but basically pleased. Before its acquisition he had been the co-founder and technical director of a small company called Dumpmines, which was in the business of digging up and processing old landfills, recovering the valuable materials that had been thrown away in a more wasteful age. It had been a surprise when Praxis had acquired them, a very pleasant surprise, as everyone in Dumpmines went from employment in a small firm, to apprentice membership in one of the richest organisations in the world—paid in its shares, voting on its policy, free to use all its resources. It was like being knighted.

      Art certainly had been pleased, and so had his wife, although she had been elegiac as well. She herself had been hired by Mitsubishi’s synthesis management, and the big transnationals, she said, were like separate worlds. With the two of them working for different ones they were inevitably going to drift apart, even more than they already had. Neither of them needed the other any more to obtain longevity treatments, which transnats provided much more reliably than the government. And so they were like people on different ships, she said, sailing out of San Francisco Bay in different directions. Like ships, in fact, passing in the night.

      It had seemed to Art that they might have been able to commute between ships, if his wife had not been so interested in one of the other passengers on hers, a vice-chairman of Mitsubishi in charge of East Pacific development. But Art had been quickly caught up in Praxis’s arbitration programme, travelling frequently to take classes or arbitrate in disputes between various small Praxis subsidiaries involved in resource recovery, and when he was in San Francisco, Sharon was very seldom at home. Their ships were moving out of hailing distance, she had said, and he had become too demoralised to contest the point, and had moved out soon afterward, on her suggestion. Kicked out, one could have said.

      Now he rubbed a swarthy unshaven jaw, re-reading the fax for the fourth time. He was a big man, powerfully built but with a tendency to slouch— “uncouth” his wife had called him, although his secretary at Dumpmines used the term “bearlike”, which he preferred. Indeed he had the somewhat clumsy and shambling appearance of a bear, also its surprising quickness and power. He had been a fullback at the University of Washington, a fullback slow of foot but decisive in direction, and very difficult to bring down. Bear Man, they had called him.