It was a dark day, the air thick with brown fines, the winds high. Another dust storm, no doubt about it. Temperatures were plummeting. Sax sniffed at a radio voice which claimed the dust storm was going global. Michel, however, was pleased. It meant they could travel during the day as well, cutting their travel time in half. “We’ve got five thousand kilometers to go, and most of it off-road. It will be wonderful to be able to travel by day, I haven’t done that since the Great Storm.”
So he and Kasei began driving round the clock, taking shifts of three hours at the wheel followed by a half hour off. Another day and they were down the Compton Break, and into tight-walled Ius Chasma, and Michel relaxed.
Ius was the narrowest of all the canyons in the Marineris system, only twenty-five kilometers wide when it left the Compton Break, dividing Sinai Planum from Tithania Catena. The canyon was a deep slash between these two plateaus, its side cliffs a full three kilometers high; a long, narrow giant of a rift. But they only saw the walls in glimpses, through bubbles of open air in the blowing dust. They continued to follow a level but rock-strewn route, making good progress through all of a long dim day. It was quiet in the car, the radio turned down to decrease the irritation of the static. The cameras’ views, higher than the windows, were of dust whipping past them so that it seemed they hardly moved. Often it looked as if they were slewing sideways. It was hard driving, and Simon and Sax spelled Michel and Kasei, following their directions. Ann was still not talking, and they did not ask her to drive. Sax drove with one eye on his AI screen, which was giving him atmospheric readouts. She could tell from across the car that the AI was indicating that the impact of Phobos was thickening the atmosphere a great deal, projected to as much as a fifty-millibar addition, an extraordinary amount. And the newly smashed craters were still outgassing. Sax noted this change with his owlish satisfaction, oblivious to the death and destruction that came with it. He noticed her glare and said, “Like the Noachian Age, I suppose.” He nearly added more, but Simon silenced him with a look, and changed the subject.
In the next car Maya and Frank passed the hours by calling over and asking Michel questions about the hidden colony, or discussing with Sax the physical changes occurring, or speculating about the war. Hashing it all over endlessly, trying to make sense of it, to figure out what had happened. Talking talking talking. On Judgment Day, Ann thought, as all the quick and the dead staggered around together, Maya and Frank would still be talking, trying to figure out what had happened. Where they had gone wrong.
Their third night out, the two cars ran down the lower end of Ius, and came to a long lemniscate fin dividing the canyon. They followed the official Marineris Highway down the south fork. In the last hour before dawn, they caught sight of some clouds overhead, and the dawn was much lighter than those of the previous days. It was enough to send them to cover, and they stopped in a fall of boulders stacked against the foot of the canyon’s south wall, and gathered in the lead car to wait out the day.
Here they had a view out over the broad expanse of Melas Chasma, the biggest canyon of them all. Ius’s rock was rough and blackish in comparison to the smooth red floor of Melas; it seemed to Ann possible that the two canyons were made of rock from ancient tectonic plates, once moving past each other, now juxtaposed forever.
They sat through a long day, talked out, tense, exhausted, their hair oily and uncombed, their faces grimy with the ubiquitous red fines of a dust storm. Sometimes there were clouds, sometimes haze, sometimes sudden pockets of clarity.
In mid-afternoon, without any warning at all, the rover rocked on its shock absorbers. Startled to attention, they jerked up to look at the TVs. The rover’s rear camera was pointed back up Ius, and suddenly Sax tapped the screen displaying its view. “Frost,” he said. “I wonder . . .”
The camera showed the frost steam thickening, moving down-canyon toward them. The highway was up on a bench above the main floor of Ius’s south fork; and this was lucky, because with a roar that shook the rover, that main floor disappeared, overwhelmed by a low wall of black water and dirty white mush. It was a juggernaut of ice chunks, tumbling rocks, foam, mud and water, a slurry throwing itself down the middle of the canyon. The roar was like thunder. Even inside the car it was too loud to talk, and the car trembled under them.
Below their bench, the canyon floor proper was perhaps fifteen kilometers across. The flood filled this whole expanse in a matter of minutes, and promptly began to rise against a long talus slope that ran out from the cliff down-canyon from them. The surface of the flood settled as it pooled against this dam, and froze solid as they watched: a lumpy discolored chaos of ice, strangely stilled. Now they could hear themselves shout over the cracks and booms and omnipresent roaring, but there was nothing to say. They only stared out the low windows or at the TVs, stunned. The frost steam coming off the flood’s surface lessened to a light fog. But no more than fifteen minutes later the ice lake burst at its lower end, rupturing in a surge of black steaming water that tore the talus dam away, with an explosive roar of avalanching rock. The flood poured down-canyon again, its leading edge beyond their view, down the great slope from Ius into Melas Chasma.
• • •
Now there was a river running down Valles Marineris, a broad, steaming, ice-choked deluge. Ann had seen videotape of the outbreaks in the north, but she hadn’t been able to get to one to see it in person. Here in the flesh, she found it almost impossible to grasp. The landscape itself was now speaking a kind of glossolalia. The inchoate roar smashed at the air, and quivered their stomachs like some bass tearing of the world’s fabric. And it was visual chaos as well, a meaningless jumble that she couldn’t seem to focus on, to distinguish near from far, or vertical from horizontal, or moving from still, or light from dark. She was losing the ability to read meaning from her senses. Only with great difficulty could she understand her companions in the car. She wasn’t sure if it was her hearing or not. She couldn’t stand to look at Sax, but then Sax she at least understood. He was trying to hide it from her, but it was clear he was excited by what was happening. That calm dead exterior had always masked a passionate nature, and she had always known it. Now he was high-colored as if he had a fever, and he never met her eye; he knew that she knew what he felt. She despised his shirking inability to confront her, even if it did arise from some kind of consideration for her. And the way he stayed always busy at his screen— he never actually looked out the low floor windows of the rover, to see the flood with his own eyes. The cameras have a better view, he would say mildly when Michel urged him to have a look. And after only a half hour of watching the first arrival of the flood on the TVs, he had gone to his AI screen to work out what it might mean to his project. Water rushing down Ius, freezing, breaking up and rushing down again; certainly into Melas; whether there would be enough water to make it into Corprates, and then down into Capri and Eos, and then down into the Aureum Chaos . . . it seemed unlikely on the face of it, but the Compton Aquifer had been big, one of the biggest ever found. Marineris very likely owed its existence to outbreaks from earlier incarnations of the same aquifer, and the Tharsis Bulge had never stopped outgassing . . . She found she was lying on the floor of the rover, watching the flood, trying to comprehend it. She tried to calculate its flow in her head, just as a way to focus better on what she saw, to bring it back out of the meaninglessness that threatened to overwhelm her. Despite herself she felt the fascination of the calculation, and of the view, and even of the flood itself; this had happened on Mars before, billions of years ago, and probably just like this. There were signs of catastrophic floods all over, beach terraces, lemniscate islands, channel beds, scablands . . . And the old broken aquifers had refilled, from the Tharsis upwelling and all the heat and outgassing that that engendered. It would have been slow, but give it two billion years. . . .
She forced herself to focus, to see. The near edge of the flood was about a kilometer away, and 200 meters below them. The foot of the northern wall of Ius wa
s about fifteen kilometers away, and the flood stretched right to it. The flood was perhaps ten meters deep, judging by the giant boulders that rolled downstream like Big Man’s bowling balls, smashing ice to shards and leaving steaming black polynyaps in their wake. The water in the open patches seemed to be moving at perhaps thirty kilometers an hour. So (punching figures into her wristpad) perhaps four-and-a-half-million cubic meters per hour. That was about a hundred Amazons out there, but running irregularly, freezing and bursting in a perpetual series of ice dams building and failing, whole steaming lakes leaping downhill over whatever channel or slope they found themselves on, stripping the land down to bedrock and then tearing the bedrock away.. . . Lying on the floor of the rover, Ann could feel that assault in her cheekbones, vibrating the ground in a rapid pounding. Such tremors hadn’t been felt on Mars in millions of years, which explained something else that she had seen but not been able to comprehend; the northern wall of Ius was moving. The rock of the cliffs was flaking off and falling into the canyon, which shook the ground, and triggered more collapses, and giant waves that washed out into the flood, water pouring back upstream over the ice, the rock bursting apart in explosions of hydration, the frost steam pouring so thickly into the dust-choked air that she could see the northern wall only in snatches.
And without a doubt the southern wall would be collapsing in a similar way, although their view of this wall, which loomed over their road to the right, was foreshortened and cut off. But it had to be falling. And if it flaked off above them, then they were dead for sure. It was quite possible— very possible. Judging by her glimpses of the north wall, the chances might be as high as 50 percent. But then it was probably worse over there; the northern wall appeared to be undercut by the flood, while the south wall was removed from it by the bench they were driving over. So the southern cliffs should be a bit more stable—
But then something drew her eye forward, downstream from them. Up there the south wall was indeed collapsing, falling in great sheets of rock. The base of the cliff exploded in a cloud of dust that bloomed over the talus, and the upper sections of the cliff slid down into this new cloud of dust and disappeared. After a second the whole mass reappeared flying horizontally out of the cloud, a strange sight. The noise was painfully loud, even inside the car; then it was just a long slow landslide down into the flood, the rocks crushing the ice and blocking the flow beneath. An instant dam, cutting off much of the flow down-canyon; and so the banks of the flood began to rise. Ann watched the icy sheet of the shoreline below her rupture, and then it was chunks of ice, jostling in a sea of black smoking fizzing water, rising swiftly toward the rover. It would engulf them if the land-slide dam lasted long enough. Ann peered at the long black spill of rock ahead of them; only a strip of it was still visible above the flood. But the slush beneath her continued to rise. It was a race of sorts. Big Man’s bathtub, draining while he poured new bucketfuls in. The speed of the lake’s ascent caused Ann to raise her estimate of the flow rate. She felt paralyzed, disconnected, in some curious sense serene; it was a matter of indifference to her whether or not the dam broke before the flood reached them. And in the overwhelming roar she felt no need to communicate with the others about this; it was impossible. She found that in a way she was cheering the flood on. It would serve them all right.
But then the landslide dam disappeared under the discolored slurry, and it all rolled off downstream in a stately collapse, the short-lived lake dropping as she watched, ice blocks on its surface clattering together, shrieking and booming as they collided and jumbled around and shot high into the air, all fantastically loud, every audible pitch roaring at once. It had to be well over a hundred decibels. She had her fingers in her ears. The car was bouncing up and down. She could see more landslides from the cliffs farther downstream, no doubt undercut by the sudden surge of the flood; the tremors they caused were triggering further collapses, until it looked like the whole canyon would fill. It seemed impossible in all the noise and vibration that their little cars would survive. The travelers clutched their chair arms or lay there on the floor like Ann, isolated by the roar, their veins pumping with an awful mix of ice and adrenaline; even Ann, who did not care, found her breath short and her muscles tensed against the kinetic assault.
When they could hear each other’s shouts again, they asked Ann what had happened. Dully she stared out the window, ignoring them. Apparently they were going to survive, for the moment at least. The flood surface was now the most shattered chaotic terrain she had ever seen, the ice pulverized to a plain of wicked shards. The high point of the lake had climbed their bench until it had been only a hundred meters downslope from them; the reexposed wet ground down there had turned from rusty black to dirty white in less than twenty seconds. Freezing time on Mars.
• • •
Sax had stayed in his seat through all that, absorbed by the flickering on his screen. A lot of water would evaporate, or rather freeze and sublime, he muttered to no one as he worked. It was very pure water, almost distilled, but it would end up as dust-filled snow, falling somewhere else. The atmosphere might get hydrated enough so that it would snow several times, or even on a regular basis, in cycles of precipitation and sublimation. Thus the floodwater would get distributed pretty evenly planetwide, except perhaps at the highest altitudes. Albedo would rise dramatically. They would have to lower it, presumably by encouraging the snow algae that the Acheron group had created. (But there was no more Acheron, Ann said to him in her mind.) Black ice would melt by day, then freeze at night. Sublimate and precipitate. And thus they would have a waterscape: streams collecting, pooling, running downstream, freezing and expanding in cracks in the rock, subliming and snowing and melting and running again. A glaciated or muddy world, most of the time. But a waterscape nevertheless.
And every single feature of the primal Mars would melt away. Red Mars was gone.
Ann lay there on the floor by the window. Her tears poured out of her to join the flood; over the dam of her nose, downstream until her right cheek and ear and the whole side of her face was wet.
• • •
“This will complicate the process of getting down-canyon,” Michel said with a little Gallic smile, and from the next car Frank laughed. In fact it looked as if it would be impossible for them to proceed even five kilometers. Directly before them the canyon highway was buried under the great landslide, completely gone. The new spill of rock was shattered and unstable, sapped from below by the flood, pounded from above by subsequent mass wasting of the new slope.
For a long time the others debated even making a try. They had to speak loudly to be heard over the jet-engine roar of the flood, which still swept past with no sign of a let-up. Nadia considered the slope suicidal, but Michel and Kasei were pretty sure they could find a way, and after a long day’s reconnaissance on foot they managed to convince Nadia to agree to try it, and the rest were willing if Nadia was. And so the day after that, protected from surveillance by the general dust storm and the flood’s steam, they divided into the two cars and drove slowly out onto the slide.
It was a rough mass of gravel and sand, liberally sprinkled with boulders. There was, however, a zone corresponding to the bench below it, which was relatively level. This zone was the only thing that made passage possible; it was a matter of finding an unobstructed way over a surface like poorly mixed cement, around boulders and past the occasional gaping hole. Michel drove the lead car boldly, with a stubbornness verging on the reckless. “Desperate measures,” he declared cheerily. “Can you imagine getting on this kind of ground in the normal course of things? It would be insane.”
“It’s insane now,” Nadia said sourly.
“Well, what can we do? We can’t go back, and we can’t give up. These are the times that try men’s souls.”
“Women, however, do fine.”
“I was quoting. You know what I mean. There’s simply no possibility of going back. The head of Ius will be flooded wall to wall. I suppose it�
��s this that makes me somehow happy. Have we ever been so free of choices? The past is wiped out, all that matters is now. The present and the future. And the future is this field of stones, and here we are. And, you know, you never really summon all of your strength until you know that there’s no way back, no way to go but onward.”
And so onward they went. But Michel’s sanguinity was sharply reduced when the second car collapsed into a hole that had been concealed by a kind of trapdoor arrangement of boulders. With some work they were able to open the front lock and pull out Kasei, Maya, Frank and Nadia. But there was no chance whatsoever of freeing the second car, they didn’t have the lift or the leverage. So they transferred all the supplies out of it, until the lead car was absolutely stuffed. And they moved on, eight of them and their supplies, all now in a single car.
• • •
Beyond the landslide, however, it got easier. They followed the canyon highway down into Melas Chasma, and found that the road had been built close to the south wall, and as Melas was such a broad canyon the flood had had room to spread out, and had bowed off some ways to the north. It still sounded like air miners were running at full capacity right outside their lock, but the road was well above and to the south of the flood, which was releasing veils of frost steam that filled the chasm, and obscured any views farther north.
Red Mars Page 61