by Paul McAuley
But there was always a garden habitat or settlement or oasis or shelter over the next horizon, built by tireless robot construction gangs everywhere across the surface. And too often now the oases had been claimed by refugees from Paris. There was no escaping the war.
Karyl drove ever westward, crossing the long trough of Palatine Linea and the southernmost edge of the bright frosts flung across half Dione's globe in wispy swirling patterns by explosive venting from deep fractures, created when ammonia-water melted by residual heat in the lithosphere had intruded on pockets of methane and nitrogen clatherates. After ten days or so, he stopped at the garden habitat of the the Fifer-Targ clan and was woken in the middle of the night: the ships of the Brazilian and European joint expedition were on the move, breaking orbit around Mimas and heading out for different moons. Members of the clan were packing and rounding up livestock, following a plan they'd worked up for just this eventuality, preparing to leave their big, tented habitat for shelters. They refused Karyl's offer of help, so he wished them luck and left them to it and drove off. It was night out on the surface, too. The habitat had been built in short string of low craters created when several vent pits had collapsed, with all the lights switched on inside, its domes shone like a string of glass beads in the black moonscape under Saturn and the swathes of fixed stars, a target that dwindled behind Karyl and quickly sank below the horizon.
Karyl picked his way across the moonscape by the mellow light of Saturnshine. He had suppressed the urge to call Dana and ask if she was all right. Maybe later he'd call her mother, who had been somewhat sympathetic to him. Right now, he needed to work out what he was going to do. He avoided roads and cut directly north-east, towards the southern end of Latium Chasma. One of his caches was tucked into the east wall of the chasma; he could pitch camp there and find out what was happening and figure things out. Wait things out for four or five weeks if he had to, or load up with supplies and follow the chasma's long straight trough north, into the fractured labyrinth of Tibur Chasmata, where there were any number of hiding places.
He felt oddly calm as he drove. Just an acid edge biting in his stomach. The worst thing had happened, and he was still free and safe. Scanning through the net, he picked up a report that some hotheads had fired a chunk of ice at the camp the Pacific Community had set up on Phoebe. Brazilian singleships had intercepted it and blown it up with an H-bomb, but some fragments had hit Phoebe nevertheless. Here was a video showing the truncated oval of the little moon, sudden stars winking and fading around its middle. Here was a video of some kind of rally in Paris, the hothead mayor roaring out at an ecstatic crowd packing a park edge to edge. That was yesterday evening. And all the ships from Earth were on the move now, the Brazilian flagship heading for Dione and two other ships heading for Rhea and Enceladus, the Pacific Community ship heading away from Phoebe, inwards towards Iapetus.
Karyl thought that aiming a bolide at them was definitely the kind of thing the crazy woman, Shizuko, would do. Her yellow eyes gleaming with certainty. Her sure touch on his arm, trying to drag him into her craziness. She'd looked a little like Dana, he realized. He was better off alone. He knew Dione as well as anyone. He would survive this.
He had been driving for an hour when the net fell over. All communication links gone. Nothing on any radio channel but the faint garbled whine of encrypted signals here and there. The little satellites that bounced signals around Dione must have been crippled or destroyed. It was happening. It was very definitely happening.
Karyl felt a sudden chill, all over. The dim moonscape all around was as still and empty as ever, and Saturn and the stars crowded everywhere else in the black sky were unchanged, but he felt horribly vulnerable. Elevated and exposed in his chair in the rolligon's bubble, pinlights gleaming on the dash, the whir of the air conditioning, clicks of valves and pumps, noises he usually didn't notice because they were always there suddenly intrusive. The pumping of his heart. The singing of his blood in his ears.
He checked his map and drove on, and soon a low flat hill appeared beyond the horizon, doubling it, rising higher. It was the rim of Pompey Crater, an arc of lobate and dissected cliffs rising a hundred metres above the plain. He drove up a natural ramp between two slumped folds of ice and parked in the shadow. The cliff reared up to the east, cutting off half the sky. Saturn's waning crescent hung high above; he was close to the equator. Everywhere else the stars spread across the black sky. Presently, he saw what he'd been looking for. A swift point of light dropping through the crowds of fixed stars, moving from east to west. The flagship of the Brazilian and European joint expedition. The Glory of Gaia. It dropped past the horizon and nothing else moved in the sky and the radio channels were silent and the net was still down.
It occurred to Karyl that although it was parked in shadow the rolligon could easily be picked up by radar of thermal imaging. He debated suiting up and climbing out and finding a hiding place for the duration, but nowhere would ever be safe now, and he couldn't hide out in his suit forever, so he stayed where he was. Heated a meal and ate it. He'd noted the ship's speed and was ready when it came back less than two hours later. There were several smaller lights around it; shuttles or gigs, some kind of landing craft. When it came around a third time, the sun had risen, and although its disc was blocked by the rim of the crater, all the stars had faded. The ship from Earth was a solitary point of light, very bright. The shuttles had gone. Landed at Paris, no doubt. The city was four hundred kilometres to the east. Not that far, really. A long day's drive. One tenth of the circumference of Dione. Suddenly, the moon seemed very small . . .
Karyl fell asleep and woke up with a little start a few hours later. Still nothing on the radio or the net. The shadow of the crater rim cliff stretched across the rippled ejecta apron had noticeably shrunken. Soon he wouldn't be in shadow anymore. And he couldn't stay here forever; he hadn't been able to refuel at the Fifer-Targ habitat because they had been too busy topping up their caravan of rolligons, and if he had to make more air he'd have to use fuel he needed to get to the cache. It was a simple equation complicated by the unknown factor of the war. Of what the Brazilians and Europeans planned to do. Whether they were simply going to take out Paris, or try to zap everything on the surface of Dione, right down to rolligons, maybe even people in pressure suits out on the surface. Call it the X factor. X, the unknown.
At last he decided that they'd find him here as easily as anywhere else. And he couldn't stay here forever anyway. So he started up the rolligon and drove north and east. Feeling like a bug crawling across a microscope slide. Looking all around him to begin with, then concentrating on driving because if they zapped him with an X-ray or gamma-ray laser of fired a missile at him he'd never know. He didn't feel scared, exactly. Instead, he was filled with a kind of careless exhilaration and was driving a shade too fast, the rolligon's rear trying to slide left or right when he hit downgrades, ploughing up feathers of icy dust either side.
Thinking of what he needed to do, and thinking of what might have been. It wasn't the last time he'd struck out into the unknown. He remembered the awful last argument with Dana, the last in a series of arguments over nothing really, nothing but the fact that they were very different people who wanted very different things. The feistiness he'd admired when he first met her, her adventurousness, was deeply ingrained. She'd been very much in favour of heading up and out, into the outer dark. Striking out for new territory. Shaking things up. And he'd wanted nothing more than simply domesticity. A quiet life with her and her family and, yes, children. It hadn't helped that her mother had sided with him. So it had all fallen apart, and that future had been taken from him, and here he was now, thinking about the predictable routines that had also been taken from him, the future unknowable now. X. X the unknown. He was as free as Dana had always wanted to be. He hoped she was all right. That she hadn't joined "our thing". Although it would be just like her.
So he drove on, at last meeting a road that ribboned across the
lightly cratered plain and turning on to it, really making speed now. It was the usual graded construction of ice gravel, built by robot crew, consolidated by treatment with pulsed infrared lasers, twenty metres wide and absolutely level and with guides along its edges so that Karyl didn't even have to steer the rolligon, it drove itself. He stretched and did some isometric exercises to try to loosen the rigid bar across his shoulders, went into the galley and made a mug of lemon tea, and came back and saw a line gleaming across the horizon. It was the railway that ran all the way around Dione. He'd reached the equator.
3.
The railway was a single track elevated above the plain on pylons like a bridge spanning the horizons, another vast engineering project built by the patient and unceasing labour of robot crews. The road ran right under it. Karyl sipped his tea, looking all around, wary again. The railway was important. It could be a target. To the west, something gleamed on the elevated track. A railcar. Stationary. Stranded. He set down his mug of tea and took the wheel of the rolligon and bumped off the road and drove towards it, the nape of his neck and his palms prickling. But he couldn't not look.
The railcar was bullet-shaped, capped at its rear with a blank cargo space, the rest a diamond canopy over a cabin floored with cushions and low couches. It had been heading west, away from Paris, and sat now grounded on the superconducting magnetic track. So the power had been cut off along the railway. Or at least, along this section. As Karyl drew near he saw that the railcar's door had been cracked open. He parked and studied it. It sat gleaming above him, skylined against velvety black. People had been riding it; the power had cut off and it had grounded; its passengers had cracked the door and climbed out. So where were they now?
He drove on slowly, and at the foot of the next support pylon found a muddle of tracks and a low mound. He knew what it was, but he had to see. He suited up and climbed out and walked across the muddle of bootprints to the mound. A sheet of magnesium alloy covered with white rubber on one side, it looked like part of the floor of the railcar, had been laid over a body and partly covered with icy dust scooped from the regolith. The body was in a pressure suit. Karyl could see an elbow, the sole of a boot. It looked like an ordinary pressure suit. He supposed that pressure suits worn by soldiers from Earth would be different, and couldn't think why soldiers would be riding in a railcar. So they had probably been refugees. Fleeing from Paris. And one of them had been hurt, mortally wounded, and had died. So when the railcar had stopped the others had carried the body out of the railcar and buried here and gone on.
He cast around and quickly discovered that the bootprints resolved into a path that headed out west, following the railway towards Ovid Crater. The next station was on the eastern rim of Ovid Crater, some thirty kilometers away. Karyl wondered why they hadn't climbed back onto the railway track and walked along it, but supposed that they had been worried that it might have started up again. Or that they might be easy targets, if the enemy was patrolling the area.
He studied the winding trail of bootprints and figured that there were five people, maybe six. He looked towards the horizon but nothing moved there. Nothing moved all around him. It would take them the best part of a day to reach the station and he wondered how much air they had left, then if any more of them had been hurt.
"You're just asking for trouble," he said out loud, then climbed back into the rolligon and drove on parallel to the railway. Maybe the people needed help; maybe they had news.
The railway strode straight on, the pylons growing taller as the land descended into a broad and shallow depression caused by partial collapse of the lithosphere during the eruption that had formed Ovid Crater, a volcanic dome that had fallen in on itself to form a classic pit crater. Vents beyond it had spewed ammonia-rich meltwater that had carved the channel of Latium Chasma, following a fault line and cutting through a string of smaller pit craters had formed from previous intrusions.
The tracks went straight down the shallow six degree slope of the depression, skirted a string of small impact craters. Once, Karyl saw an orange bottle someone had discarded. The ground pitched up and a low ridge rose beyond the close horizon, the place where the side of the depression met the rim of Ovid Crater, some ten kilometres away. The railway strode on over crevasses and pressure ridges; as Karyl manoeuvered the rolligon around these obstructions he lost the trail of bootprints and had to backtrack. The path turned north, where the crater rim was lower and a natural piste led up to the station at the ridge. And where there was an oasis, built on a flat-topped abutment with big views all around: Karyl had stopped there several times.
He drove on a little way, and saw four, five, six, figures in pressure suits of various colours at the horizon. Slogging along, turning when he used a line-of-sight channel to raise them, and ask them who they were, and if they needed a lift.
4.
They had come from Paris, had taken the last railcar out of the rimtop station when the first Brazilian dropships had flared in above the spaceport. Perhaps the only railcar to escape, who knew? The mayor had ordered the spur line that connected Paris with the trans-equatorial railway shut down two days ago, but when the battle for Paris had begun the peace wardens guarding the station had deserted their posts, and the six men and women, all of them part of the railway crew, all of them from other cities in the Saturn System with no especial loyalty to Paris or its suicidally aggressive stance, had decided to take a chance and run for it.
They'd overridden the AI that had shut the spur line down, climbed into a railcar and started it manually, and had scarcely set off when packages had begun to rain down from the sky, inflated impact bags bouncing across the ground between the spaceport and the bottom edge of the city, the bags torn apart by the robots inside, deadly things on tall tripod legs, very fast. The robots and soldiers jetting down attacking and overwhelming the defenses around the lower part of the city, the swift unequal battle witnessed by the railcar's passengers as it carried them around the top of the curved rim of Romulus Crater. One of the Brazilian craft had flown straight past them, passing just a few hundred metres away. The wash of its drive had scorched one side of the railcar. And then the city had fallen below the horizon, and they had begun to believe that they had escaped when a tremendous light had flared across half the horizon, and the railcar had slammed to a stop and a quake had jolted it so hard they thought it might topple off. One of the city's fusion reactors that had blown. So they'd climbed down from the railcar and hiked fifty kilometers to the junction with the trans-equatorial railway. They'd reached the station exhausted and almost out of air, and that was when one of their number had suffered a fatal heart attack and died, despite their best efforts. They'd rested up, and then caught a railcar heading west; the trans-equatorial railway had its own power supply. And then someone must have shut the railway down, and they had been stranded again. So they had buried their dead companion and set off on another hike, and had been fast running out of air when Karyl had picked them up.
It had been an amazing adventure, and they were eager to tell Karyl all about it as he drove them towards the oasis, the five of them crowded into the space behind his driving seat, bulked out in their pressure suits, noisy and euphoric. Talking over each other, an excited chatter like parrots. Telling that he was their hero. That he had saved their lives.
"We didn't have enough air to reach the station or the nearest oasis," their leader, a woman named Aida, told Karyl. "Our plan was that four of us give most of what we had left to Vincent, he's our strongest walker, and then go into deep sleep and hope he could bring back people to rescue us. But instead you turned up, just in time."
"My karma is your karma," one of the men, Simon said.
Their exuberance didn't abate all the way to oasis at Dvoskin's Knoll, where the five survivors spilled out of the lock and immediately began telling their story to the fifty or so people who'd taken refuge there, who had every kind of question about the battle for Paris, most of which the survivors couldn't
answer. Had the city fallen? How many had been killed? What did the Brazilians plan to do next? What was happening to the other cities on the other moons? All of this had a sobering effect on the survivors. Simon mentioned the companion who had died, who they'd had to leave behind in a temporary grave. Aida asked Karyl if he would take her back there tomorrow, so that they could give him a proper mourning ceremony, and gift his carbon and phosphorous and nitrogen and other nutrients to the ecosystem of the oasis.
