She stared at him, mouth full of toast.
Later that week she abandoned Sheffield and went south again, joining a caravan of people working their way from crater to crater, installing drainage systems. Every crater had variations, but essentially it was a matter of picking the right angle to emerge from the crater apron, and then setting the robots to work. Von Karman, Du Toit, Schmidt, Agassiz, Heaviside, Bianchini, Lau, Chamberlin, Stoney, Dokuchaev, Trumpler, Keeler, Charlier, Suess . . . they plumbed all of those craters, and many more unnamed ones, although the craters were taking on names even faster than they drilled them: 85 South, Too Dark, Fool’s Hope, Shanghai, Hiroko Slept Here, Fourier, Cole, Proudhon, Bellamy, Hudson, Kaif, 47 Ronin, Makoto, Kino Doku, Ka Ko, Mondragon. The migration from one crater to the next reminded Nadia of her trips around the south polar cap during the underground years; except now everything was out in the open, and through the nearly nightless midsummer days the team luxuriated in the sun, in the glary light off the crater lakes. They traveled across rough frozen bogs brilliant with sunny meltwater and meadow grass, and always of course they crossed the rust-and-black rockscape breaking out into the light, ring after ring, ridge after ridge. They plumbed craters and laid watershed pipes, and attached greenhouse-gas factories to the excavators whenever the rock had any gas feedstocks in it.
But hardly any of that turned out to be work in the sense Nadia meant. She missed the old days. Of course operating a bulldozer had not been hand labor, but one’s touch with the blade had been a very physical skill, and the repeated gearshifts physically taxing; and it was all around a higher level of engagement than this “work,” which consisted of talking to AIs and then walking around and watching humming and buzzing teams of waist-high robot diggers, city-block-sized mobile factory units, tunnel moles with diamond teeth that grew back like sharks’ teeth— everything made of bioceramic/metallic alloys stronger than the elevator cable, all of it out there doing it all by itself. It just wasn’t what she had in mind.
Try again. She went through another cycle; return to Sheffield, engagement in the council work, increasing disgust, merging with despair; look around for anything to get her out of it; notice some likely project and seize on it. Run off to check it out. Like Art had said, she could call her own shots. There was that in power too.
The next time out it was soil that drew her. “Air, water, earth,” Art said. “Next it’ll be forest fires, eh?”
But she had heard that there were scientists in Bogdanov Vishniac trying to manufacture soil, and this interested her. So off she went, flying south to Vishniac, where she had not been for years. Art accompanied her. “It’ll be interesting to see how the old underground cities adapt, now that there’s no need to hide.”
“I don’t see why anyone stays down here, to tell you the truth,” Nadia said as they flew down into the rugged southern polar region. “They’re so far south their winters last forever. Six months with no sun at all. Who would stay?”
“Siberians.”
“No Siberian in his right mind would move here. They know better.”
“Laplanders, then. Inuit. People who like the poles.”
“I suppose.”
As it turned out, no one in Bogdanov Vishniac seemed to mind the winters. They had redistributed their mohole mound in a ring around the mohole itself, creating an immense circular amphitheater facing down into the hole. This terraced amphitheater was to be the surface Vishniac. In the summers it would be a green oasis, and in the dark winters a white oasis; they planned to illuminate it with hundreds of brilliant streetlights, giving themselves a stage set day, in a town contemplating itself across a round gap in things, or from the upper wall looking out at the frosted chaos of the polar highlands. No, they were going to stay, no question of it. It was their place.
Nadia was greeted at the airport as a special guest, as always when she stayed with Bogdanovists. Before joining them this had struck her as ridiculous, and even a bit offensive: girlfriend of The Founder! But now she accepted their offer of a guest suite located on the lip of the mohole, with a slightly overhanging window that gave one a view straight down for eighteen kilometers. The lights on the mohole’s bottom looked like stars seen through the planet.
Art was petrified, not at the sight but at the very thought of the sight, and he would not go near that half of the room. Nadia laughed at him, and then when she was done looking, closed the drapes.
The next day she went out to visit the soil scientists, who were happy at her interest. They wanted to be able to feed themselves, and as more and more settlers moved south, this was going to be impossible without more soil. But they were finding that manufacturing soil was one of the most difficult technical feats they had ever undertaken. Nadia was surprised to hear this— these were the Vishniac labs, after all, world leaders in technologically supported ecologies, having lived for decades hidden in a mohole. And topsoil was, well, soil. Dirt with additives, presumably, and additives one could add.
No doubt she conveyed some of this impression to the soil scientists, and the man named Arne leading her around told her with some exasperation that soil was in fact very complex. About five percent of it by weight was made of living things, and this critical five percent consisted of dense populations of nematodes, worms, mollusks, arthropods, insects, arachnids, small mammals, fungi, protozoa, algae, and bacteria. The bacteria alone included several thousand different species, and could number as high as a hundred million individuals per gram of soil. And the other members of the microcommunity were almost as plentiful, in both number and variety.
Such complex ecologies could not be manufactured in the way Nadia had been imagining, which was basically to grow the ingredients separately and then mix them in a hopper, like a cake. But they didn’t know all the ingredients, and they couldn’t grow some of the ingredients, and some that they could grow died on mixing. “Worms in particular are sensitive. Nematodes have trouble too. The whole system tends to crash, leaving us with minerals and dead organic material. That’s called humus. We’re very good at making humus. Topsoil, however, has to grow.”
“Which is what happens naturally?”
“Right. We can only try to grow it faster than it grows in nature. We can’t assemble it, or manufacture it in bulk. And many of the living components grow best in soil itself, so there’s a problem providing feedstock organisms at any faster rate than natural soil formation would provide them.”
“Hmm,” Nadia said.
Arne took her through their labs and greenhouses, which were filled with hundreds of pedons, tall cylindrical vats or tubes, in racks, all holding soil or its components. This was experimental agronomy, and from her experience with Hiroko Nadia was prepared to understand very little of it. The esoterica of science could go right off her scale. But she did understand that they were doing factorial trials, altering the conditions in each pedon and tracking what happened. There was a simple formula Arne showed her to describe the most general aspects of the problem:
S = f(PM,C,R,B,T),
meaning that any soil property S was a factor (f) of the semi-independent variables, parent material (PM), climate (C), topography or relief (R), biota (B), and time (T). Time, of course, was the factor they were trying to speed up; and the parent material in most of their trials was the ubiquitous Martian surface clay. Climate and topography were altered in some trials, to imitate various field conditions; but mostly they were altering the biotic and organic elements. This meant microecology of the most sophisticated kind, and the more Nadia learned about it the more difficult their task seemed— not so much construction as alchemy. Many elements had to cycle through soil to make it a growth medium for plants, and each element had its own particular cycle, driven by a different collection of agents. There were the macronutrients— carbon, oxygen, hydrogen, nitrogen, phosphorus, sulfur, potassium, calcium, and magnesium— then the micronutrients, including iron, manganese, zinc, copper, molybdenum, boron, and chlorine. None of these nutrie
nt cycles was closed, as there were losses due to leaching, erosion, harvesting, and outgassing; inputs were just as various, including absorption, weathering, microbial action, and application of fertilizers. The conditions that allowed the cycling of all these elements to proceed were varied enough that different soils encouraged or discouraged each cycle to different degrees; each kind of soil had particular pH levels, salinities, compaction, and so forth; thus there were hundreds of named soils in these labs alone, and thousands more back on Earth.
Naturally in the Vishniac labs the Martian parent material formed the basis for most of the experiments. Eons of dust storms had recycled this material all over the planet, until it had everywhere much the same content: the typical Martian soil unit was made up of fine particles of mostly silicon and iron. At its top it was often loose drift. Below that, varying degrees of interparticle cementation had produced crusty cloddy material, becoming blocky the lower one dug.
Clays, in other words; smectite clays, similar to Terra’s montmorillonite and nontronite, with the addition of materials like talc, quartz, hematite, anhydrite, dieserite, clacite, beidellite, rutile, gypsum, maghemite and magnetite. And everything had been coated by amorphous iron oxyhydroxides, and other more crystallized iron oxides, which accounted for the reddish colors.
So this was their universal parent material: iron-rich smectite clay. Its loosely packed and porous structure meant it would support roots while still giving them room to grow. But there were no living things in it, and too many salts, and too little nitrogen. So in essence their task was to gather parent material, and leach out salt and aluminum, while introducing nitrogen and the biotic community, all as fast as possible. Simple, when put like that; but that phrase biotic community masked a whole world of troubles. “My God, it’s like trying to get this government to work,” Nadia exclaimed to Art one evening. “They’re in big trouble!”
Out in the countryside people were simply introducing bacteria to the clay, and then algae and other microorganisms, then lichen, and then halophyllic plants. Then they had waited for these biocommunities to transform the clay into soils, through many generations of living and dying in it. This worked, and was working even now, all over the planet; but it was very slow. A group in Sabishii had estimated that when averaged over the planet’s surface, about a centimeter of topsoil was being generated every century. And this had been achieved using genetically engineered populations designed to maximize speed.
In the greenhouse farms, on the other hand, the soils used had been heavily amended by nutrients and fertilizers and inoculants of all kinds; the result was something like what these scientists were trying for, but the quantity of soil in greenhouses was minuscule compared to what they wanted to put out on the surface. Mass producing soil was their goal. But they had gotten into something deeper than they had expected, Nadia could tell; they had the vexed absorbed air of a dog gnawing on a bone too big for its mouth.
The biology, chemistry, biochemistry, and ecology involved in these problems were far beyond Nadia’s expertise, and there was nothing she could do to make suggestions there. In many cases she couldn’t even understand the processes involved. It was not construction, nor even an analog of construction.
But they did have to incorporate some construction into whatever production methods they tried, and there Nadia was at least able to understand the issues. She began to concentrate on that aspect of things, looking at the mechanical design of the pedons, and also the holding tanks for the living constituents of the soil. She also studied the molecular structure of the parent clays, to see if it suggested anything to her about working with them. Martian smectites were aluminosilicates, she found, meaning each unit of the clay had a sheet of aluminum octahedrals sandwiched between two sheets of silicon tetrahedrals; the different kinds of smectites had different amounts of variation in this general pattern, and the more variation there was, the easier it was for water to seep into the interlayer surfaces. The most common smectite clay on Mars, montmorillonite, had a lot of variety, and so was very open to water, expanding when wet, and shrinking when dry to the point of cracking.
Nadia found this interesting. “Look,” she said to Arne, “what about a pedon filled with a matrix of feeder veins, which would introduce the biota all through the parent material.” Take a batch of parent material, she went on, and get it wet, then let it dry. Insert into the crack systems the feeder vein matrix. Then pour in whatever important bacteria and other constitutents they could grow. Then if the bacteria and other creatures could eat their way out of their feeder veins, digesting that material as they emerged, they would all suddenly be there together in the clay, interacting. That would be a tricky time, no doubt many trials would be necessary to calibrate the initial amounts of the various biota needed to avoid population booms and crashes— but if they could get them to settle into their usual communities, then they would suddenly have living soil. “There are feeder-vein systems like this used for certain quick-setting construction materials, and now I hear that doctors feed apatite paste into broken bones the same way. The feeder veins are made of protein gels appropriate to whatever substance they’re going to contain, molded into the appropriate tubular structures.”
A matrix for growth. Worth looking into, Arne said. Which made Nadia smile. She went around that afternoon feeling happy, and that evening when she joined Art she said, “Hey! I did some work today.”
“Well!” Art said. “Let’s go out and celebrate.”
• • •
Easy to do, in Bogdanov Vishniac. It was a Bogdanovist city, all right, as buoyant as Arkady himself. A party every night. They had often joined the evening promenade, and Nadia loved walking along the railing of the highest terrace, feeling that Arkady was somehow there, had somehow persisted. And never more so than on this night, celebrating a bit of work done. She held Art’s hand, looked down and across at the crowded lower terraces and their crops, orchards, pools, sports fields, lines of trees, arcuate plazas occupied by cafés, bars, dance pavilions— bands battling for sonic space, the crowds chugging around them, some dancing but many more simply making the night’s promenade, like Nadia herself. All this still under a tent, with tenting that they hoped to remove someday; meanwhile it was warm, and the young natives wore an outlandish array of pantaloons, headdresses, sashes, vests, necklaces, so that Nadia was reminded of the video footage of Nirgal and Maya’s reception in Trinidad. Was this coincidence, or was there some supraplanetary culture coming into being among the young? And if there was, did that mean that their Coyote, the Trinidadian, had invisibly conquered the two worlds? Or her Arkady, posthumously? Arkady and Coyote, culture kings. It made her grin to think of it, and she took sips of Art’s cup of scalding kavajava, the drink of choice in this cold town, and watched all the young people moving like angels, always dancing no matter what they did, flowing in graceful arcs from terrace to terrace. “What a great little town,” Art said.
Then they came upon an old photo of Arkady himself, framed and hung on a wall next to a door. Nadia stopped and clutched Art’s arm: “That’s him! That’s him to the life!”
The photo had caught him talking with someone, standing just inside a tent wall and gesturing, his hair and beard lofting away from his head and blending into a landscape exactly the color of his wild curls. A face coming out of a hillside, it seemed, blue eyes squinting in the glare of all that red glee. “I’ve never seen a photo that looked so much like him. If he saw a camera pointed at him he didn’t like it, and the picture came out wrong.”
She stared at the photo, feeling flushed, and strangely happy; such a lifelike encounter! Like running into someone again after years of not seeing them. “You’re like him, in some ways, I think. But more relaxed.”
“It looks like it would be hard to get much more relaxed than that,” Art said, peering closely at the photo.
Nadia smiled. “It was easy for him. He was always sure he was right.”
“None of the rest of us h
ave that problem.”
She laughed. “You’re cheerful like he was.”
“And why not.”
They walked on. Nadia kept thinking of her old companion, seeing the photo in her mind’s eye. There was still so much she remembered. The feelings connected to the memories were fading, however, the pain blunted— the fixative leached out, all that flesh and trauma now only a pattern of a certain kind, like a fossil. And very unlike the present moment, which, looking around, feeling her hand in Art’s, was real, vivid, brief, perpetually changing— alive. Anything could happen, everything was felt.
“Shall we go back to our room?”
• • •
The four travelers to Earth returned at last, coming down the cable to Sheffield. Nirgal and Maya and Michel went their ways, but Sax flew down and joined Nadia and Art in the south, a move which pleased Nadia no end. She had come to have the feeling that wherever Sax went was the heart of the action.
He looked just as he had before the trip to Earth, and was if anything even more silent and enigmatic. He wanted to see the labs, he said. They took him through them.
“Interesting, yes,” he said. Then after a while: “But I’m wondering what else we might do.”
“To terraform?” Art asked.
“Well . . .”
To please Ann, Nadia thought. That was what he meant. She gave him a hug, which surprised him, and she kept her hand on his bony shoulder as they talked. So good to have him there in the flesh! When had she gotten so fond of Sax Russell, when had she come to rely on him so much?
Art too had figured out what he meant. He said, “You’ve done quite a bit already, haven’t you? I mean, at this point you’ve dismantled all the metanats’ monster methods, right? The hydrogen bombs under the permafrost, the soletta and aerial lens, the nitrogen shuttles from Titan—”