Beyond the Aquila Rift: The Best of Alastair Reynolds

THE OLD MAN AND THE MARTIAN SEA

IN THE belly of the airship, alone except for freight pods and dirt-smeared machines, Yukimi dug into her satchel and pulled out her companion. She had been given it on her thirteenth birthday, by her older sister. It had been just before Shirin left Mars, so the companion had been a farewell present as well as a birthday gift.

It wasn’t the smartest companion in the world. It had all the usual recording functions, and enough wit to arrange and categorize Yukimi’s entries, but when it spoke back to her she never had the impression that there was a living mind trapped inside the floral-patterned—and now slightly dog-eared—hardback covers. And when it tried to engage her in conversation, when it tried to act like a friend or even a sister, it wasn’t clever enough to come out with the sort of thing a real person would have said. But Yukimi didn’t mind, really. It had still been a gift from Shirin, and if she stopped the companion talking back to her—which she mostly did, unless there was something she absolutely had to know—then it was still a place to record her thoughts and observations, and a useful window into the aug. When she was seventeen she would be legally entitled to receive the implants that gave her direct access to that shifting, teeming sea of universal knowledge. For now, all she had was the glowing portal of the companion.

“I’ve done it now,” she told it. “After all those times where we used to dare each other to sneak aboard, I’ve actually stayed behind until after the doors are closed. And now we’re in the air.” She paused, tiptoeing to peer through a grubby, dust-scoured window as her home fell slowly away. “I can see Shalbatana now, Shirin—it looks much smaller from up here. I can see Sagan Park and the causeway and the school. I can’t believe that was our whole world, everything we knew. Not that that’s any surprise to you, I suppose.”

It wasn’t Shirin she was talking to, of course. It was just the companion. But early on she had fallen into the habit of making the entries as if she was telling them to her sister, and she had never broken it.

“I couldn’t have done it if we hadn’t played those games,” Yukimi went on. “It was pretty hard, even then. Easy enough to sneak onto the docks—not much has changed since you left—but much harder to get aboard the airship. I waited until there was a lot going on, with everyone running around trying to get it loaded on time. Then I just made a run for it, dodging between robots and dock workers. I kept thinking: what’s the worst that can happen? They’ll find me and take me home. But I won’t be in any more trouble than if I do manage to sneak aboard. I know they’ll find me sooner or later anyway. I bet you’re shaking your head now, wondering what the point of all this is. But it’s easy for you, Shirin. You’re on another planet, with your job, so you don’t have to deal with any of this. I’m stuck back here and I can’t even escape into the aug. So I’m doing something stupid and childish: I’m running away. It’s your fault for showing me how easy it would be to get aboard one of the airships. You’d better be ready to take some of the blame.”

It was too much effort to keep on tiptoe so she lowered down. “I know it won’t make any difference: I’m not a baby. But they keep telling me I’ll be fine and I know I won’t be, and everything they say is exactly what I don’t want to hear. It’s not you, it’s us. We still love you, darling daughter. We’ve just grown apart. As if any of that makes it all right. God, I hate being me.”

She felt a lurch then, as if the airship had punched its way through the pressure bubble that surrounded the whole of Shalbatana City and its suburbs. A ghost of resistance, and then they were through. Behind, the bubble would reseal instantly so that not even a whisper of breathable air was able to leak out into the thin atmosphere beyond.

“I’m through now,” she said, going back on tiptoe. “On the other side. I guess this is the farthest from home I’ve ever been.” The sun was catching the bubble’s edge, picking it out in a bow of pale pink. Her home, everything she really knew, was inside that pocket of air, and now it looked like a cheap plastic snow globe, like the one her aunt had sent back from Paris with the Eiffel Tower.

It hit her then. Not the dizzy sense of adventure she had been expecting, but an awful, knife-twisting sense of wrongness. As if, only now that the airship was outside the bubble, was she grasping the mistake she had made.

But it was much too late to do anything about it now.

“I’m doing the right thing, Shirin. Please tell me I’m doing the right thing.”

She slumped down with her back against the sloping wall of the cargo hold. She felt sorry for herself, but she was too drained to cry. She knew it would be a good idea to eat, but she had no appetite for the apple she had brought with her in the satchel. She closed the covers on the companion and let it slip to the hard metal deck, gaining another dent or dog-ear in the process. Sensing her mood, the cartoon characters on the side of the satchel started singing and dancing, trying in their idiotic way to perk her up.

Yukimi scrunched the satchel until they shut up.

She listened to the drone of the airship’s engines. It was a different sound now that the air outside was so much colder and thinner than inside Shalbatana City’s dome. She knew from school that the air had once been even thinner, before the changes began. But it was still not enough to keep anyone alive for very long.

There was enough air inside the cargo hold to last for the journey, though.

At least that was what Shirin had always said, and Shirin had never lied about anything. Had she?

“I THINK SOMETHING’S happening,” Yukimi told the companion.

“We’re changing course.”

They had been flying high and steady for eight hours, Mars unrolling below in all its savage dreariness, all its endless rust-red monotony. Adults were always going on about how there were already too many people on the planet, but as far as Yukimi could tell there was still a lot of empty space between the warm, wet bubbles of the settlements. Aside from the pale, arrow-straight scratch of the occasional road or pipeline, there had been precious little evidence of civilization since their departure. Unless one counted the lakes, which were made by rain, and rain was made by people, but lakes weren’t civilization, as far as Yukimi was concerned. How anyone could think this world was crowded, or even beginning to be crowded, was beyond her.

Yukimi closed the book and strained to look through the window again. It was hard to tell, but the ground looked nearer than it had been all afternoon. They didn’t seem to be anywhere near a dome. That made sense, because in the time she had been in the air, there was no way that the airship could have made it to Vikingville, let alone anywhere farther away than that.

“It’s a good sign,” she went on. “It has to be. Someone must have figured out what I did, and now they’ve recalled the airship. Maybe they even got in touch with you, Shirin. You’d have told them about our game, how easy it would be for me to escape. I’m going to be in a lot of trouble now, but I always knew that was coming sooner or later. At least I’ll have made my point.”

That was going to cost someone a lot of money, Yukimi thought. She could see her father now, shaking his head at the shame she had brought on him with her antics. Making him look bad in front of his rich friends like Uncle Otto. Well, if that was what it took to get through to her parents, so be it.

But as the airship lowered, so her certainty evaporated. It didn’t seem to be turning around, or be in any kind of a hurry to continue its journey. The engine note had changed to a dawdling throb, just enough to hold station against the wind.

What was going on?

She looked through the window again, straining hard to look down and, yes, there was something under them. It wasn’t a bubble like the one around Shalbatana, though, or even one of those settlements that was built straight onto the ground with no protection from the atmosphere. It was a machine, a huge, metallic-green, beetle-shaped juggernaut inching slowly along the surface. It was bigger than the airship, bigger than any moving thing she had ever seen with her own eyes. The machine was as long as a city district, as wide as Sagan Park. It had eight solid wheels, each of which was large enough to roll over not just her home but the entire apartment complex. And although it seemed to be crawling, that was only an illusion caused by its size. It was probably moving faster than she could run.

“I can see a Scaper,” she told the book. “That’s what I think it is, anyway. One of those old terraforming mechs.” She held the companion open and aimed down through the window, so that it could capture the view of the enormous machine, with chimneys sprouting in double rows along its back, angled slightly rearward like the smokestacks on an ocean liner. “I didn’t think there were many of them left now. I don’t think they actually do anything anymore; it’s just too much bother to shut them down.”

But for the life of her she could not imagine why the airship was now descending to rendezvous with a Scaper. How exactly was that going to get her home any quicker?

“I’m not sure about this,” she told the companion and then closed it quietly.

Through the window, she could see the airship lowering itself between the twin rows of atmosphere stacks. They were soot black and sheer, as tall as the highest buildings in Shalbatana City. The airship stopped with a jerk, the freight pods creaking in their harnesses, and then a series of bangs and thuds sounded in rapid succession, as if restraining devices were locking into place. The engine note faded away, leaving only a distant throb, one that came up from the floor. It was the sound of the Scaper, transmitted to the cargo hold.

For long minutes, nothing happened.

Yukimi was by now quite uneasy, not at all sure that this rendezvous had anything to do with her being rescued. Halting on the back of a Scaper—kilometers from anywhere—had not figured in her plans. She had always assumed that the airships went from A to B as quickly as possible. No one had ever mentioned anything about them indulging in this kind of detour.

None of this would be happening anywhere else in the solar system, she told herself. Mars was the only place where a girl could run away from home and not be found. Everywhere else, the aug was so thick, so all-pervasive, it was impossible to do anything illegal without someone knowing more or less instantly. You couldn’t hide away inside things. You couldn’t get lost.

Mars was different, as everyone liked to say. Mars was a Descrutinized Zone. The aug was purposefully thin, and that meant people had to take responsibility for their own actions. You could get into trouble on Mars. Easily.

Yukimi was pacing around, wondering what to do—with all sorts of impractical ideas flashing through her head—when the cargo doors began to open. She took in a deep breath, as if that was going to help her. But apart from a slight breeze there wasn’t any loss of pressure. As hard blue light pushed through the widening Saps where the doors were rising open, she slunk back into the shadows, hiding between two freight pods. She had put the companion back into her satchel, and she hoped neither of them would make a sound. She very much wanted to be discovered, but she also very much wanted not to be.

For a long time nothing at all happened. All she heard was faint mechanical sounds in the distance, and the continuing throb of the Scaper. She was aware now of a very slight undulation to their motion, as the colossal machine followed the terrain under its wheels.

Then she heard something approaching. The noise was patient, rhythmic, wheezing, and it was accompanied by a labored shuffling. Yukimi tensed and pushed herself even farther back, but not quite so far that she couldn’t see the cargo doors. With an agonizing slowness, something horrible came up the ramp. It was a monster.

Silhouetted, huge and bulbous against the blue light beyond, came something like a man, but swollen out of all proportion, with the head no more than a bulge between wide, ogrelike shoulders. Yukimi’s fear sharpened into a very precise kind of terror. She had never seen anything like this before. The figure stepped into the bay, and at last she saw it properly. It was wearing armor, but the armor was scratched and scabbed and rusty, and bits of it didn’t fit correctly. There were pipes and cables all over the misshapen form, with wisps of steam coming out of its joints. Green fluid dribbled out one of the knees. The bulge where its head should have been was a low bronze dome, caked in grease and dirt, with nothing at all that could pass for a face. It didn’t even have eyes. It just had cylinders sticking out of it at various angles, glassy with lenses, and some filth-smeared grills in the side of the dome. She couldn’t tell if it was a robot or some ancient, grotesquely cumbersome space suit. All she knew was that she was very, very frightened by it, and she didn’t want to know who—or what—was inside.

The figure clanked and wheezed as it moved through the cargo bay. It paused by one of the cargo pods, not far from where she was hiding. She hardly dared move in case it saw or heard her.

The figure raised one of its huge arms and scraped dirt off a shipping label. Its armored hand was big enough to crush a chair. One of the lenses sticking out of its head swiveled into place, telescoping out to peer at the label. Yukimi felt herself caught between possibilities. She wanted to be found now, no doubt about it. But she did not want to be found by this thing, whatever it was.

No one had ever told her there were monsters like this on Mars, not even Shirin, when she had been trying to scare her little sister. And Shirin had never missed a trick in that regard.

The figure moved sideways, to the next pod. It peered at the next label. If it kept that up, there was no way it was going to fail to notice Yukimi. Yet in that moment she saw her chance. There was an open-topped cargo pallet behind the two pods she was hiding between—it was only partly filled with plastic sacks of some agricultural or biomedical product. She could conceal herself in that easily—if only she could get into it without being noticed.

She listened to the figure’s wheezing. It was regular enough that she had a chance to move during the exhalation phase, when the figure was making enough noise to cover her movements. There was not going to be time to agonize about it, though. It was already moving to the next pod, and the one after that would bring it right next to her.

She moved, timing things expertly. Shirin would have been proud. She was into the open-topped pallet before the wheeze ended, and nothing in the ensuing moments suggested that she had been discovered. The figure made a sound as of another label being scuffed clean. Yukimi crouched low, cushioned on the bed of plastic sacks. They squeaked a little under her, but if she stayed still there was no sound.

She had done the right thing, she told herself. Better to take her chances on the airship than to put herself at the mercy of the creature, whatever it was. The airship would be on its way again soon. They didn’t just go missing between cities.

Did they?

The figure left. She heard it clanking and wheezing out of the bay, down the ramp, back into the Scaper. But she dared not move just yet. Perhaps it had sensed her somewhere in the bay and was just waiting for her to leave her hiding place.

Shortly afterward, something else came. It wasn’t the shuffling, wheezing figure this time. It was something big and mechanical, something that whined and whirred and made pneumatic hissing sounds. Quite suddenly, one of the freight pods was moving. Yukimi snuggled down deeper. The machine went away and then came back. She caught a glimpse of it this time as it locked onto the next pod and hauled it out of the cargo bay. It was a handler robot, similar to the ones she had seen fussing around at the docks, except maybe a bit older and less cared for. It was a big stupid lunk of a robot: yellow and greasy and easily powerful enough to crush a little girl without even realizing what it had done.

Then it came back. Yukimi felt a jolt as the robot coupled onto the open-topped pallet. Then the ceiling started moving, and she realized that she was being unloaded. For a moment she was paralyzed with fear, but even when the moment passed she didn’t know what to do. She dared move enough to look over the edge of the pallet. The floor was moving past very quickly, racing by faster than she could run. Even if she risked climbing out and managed not to break anything or knock herself out as she hit the deck, there was still a danger that the robot would run over her with one of its wheels.

No, that wasn’t a plan. It hadn’t been a good idea to hide inside the pallet, but then again it hadn’t been a good idea to sneak aboard the airship in the first place. It had been a day of bad ideas, and she wasn’t going to make things worse now.

But what could be worse than being taken into the same place as the wheezing, goggle-eyed thing?

The robot took her out of the bay, down a ramp, into some kind of enclosed storage room inside the Scaper. There were lights in the ceilings and the suspended rails of an overhead crane. Even lying down in the pallet, she could see other freight pods stacked around. With a jolt the robot lowered the open-topped pallet and disengaged. It whirred away. Yukimi lay still, wondering what to do next. It seemed likely that the airship had stopped off to make a delivery to the Scaper. If that was the case it would be on its way quite soon, and she would much rather be on it than stay behind here, inside the Scaper, with the thing. But to get back aboard now she would have to make sure the thing didn’t see her, and lying down in the pallet she had no idea if the thing was waiting nearby.

She heard a noise that sounded awfully like the cargo doors closing again.

It was now or never. She scrambled out of the pallet, catching her trousers on the sharp lip, ripping them at the knee, but not caring. She got her feet onto the floor, dragged her satchel with her, oriented herself—she could see the loading ramp, and the doors above it lowering shut—and started running. Really running now, not the pretend running she had done all her life until this moment. She had to get inside the airship again, before the doors shut. She had to get away from the Scaper.

The thing stepped in front of the ramp, blocking her escape. With dreadful slowness it raised one of its hands. Yukimi skidded to a halt, heart racing in her chest, panic overwhelming her.

The thing raised its other hand. They came together where its neck should have been, under the shallow dome that passed for its head. The huge fingers worked two rust-colored toggles and then moved up slightly to grasp the dome by the grills on either side of it. Yukimi was now more terrified than she had ever thought possible. She did not even think of running in the other direction. The thing was slow, but this was its lair and she knew that she could never escape it for good. Plodding and wheezing and slow as it might be, it would always find her.

It took off the helmet, lifting it up above its shoulders. There was a tiny head inside the armor. She could only see the top of it, from the eyes up. It had lots of age spots and blemishes and a few sparse tufts of very white hair. The rest of it was hidden by the armor.

An unseen mouth said, “Hello.”

Yukimi couldn’t answer. She was just standing there trembling. The thing looked at her for several seconds, the eyes blinking as if it, too, was not quite sure what to make of this meeting. “It is, at least in polite circles, customary to reciprocate a greeting,” the thing—the old man inside the armor—said. “Which is to say, you might consider giving me a ‘hello’ in return. I’m not going to hurt you.”

Yukimi moved her mouth and forced herself to say, “Hello.”

“Hello back.” The man turned slightly, his armor huffing and puffing. “I don’t want to seem discourteous—we haven’t even introduced ourselves—but that airship’s on a tight schedule and it’ll be lifting off very shortly. Do you want to get back aboard it? I won’t stop you if you do, but it’d be remiss of me not to make sure you’re absolutely certain of it. It’s continuing on to Milankovic, and that’s a long way from here—at least two days’ travel. Have you come from Shalbatana?”

Yukimi nodded.

“I can feed you and get you back there a sight quicker than you’ll reach Milankovic. Of course you’ll have to trust me when I tell you that, but—well—we all have to trust someone sooner or later, don’t we?”

“Who are you?” Yukimi asked.

“They call me Corax,” the old man said. “I work out here, doing odd jobs. I’m sorry if the armor scared you, but there wasn’t time for me to get out of it when I learned that the airship was coming in. I’d just come back from the lake, you see. I’d been scouting around, checking out the old place one last time before the waters rise…” He paused. “I’m wittering. I do that sometimes—it comes of spending a lot of time on my own. What’s your name?”

“Yukimi.”

“Well, Yukimi—which is a very nice name, by the way—it’s your call. Back on the airship and take your chances until you reach Milankovic—miserable arse-end of nowhere that it is. You’ll need warm clothing and enough food and water to get you through two days, and maybe some supplementary oxygen in case cabin pressure drops. You’ve got all that, haven’t you? Silly question, really. A clever looking girl like you wouldn’t have stowed away on a cargo airship without the necessary provisions.”

Yukimi held up her satchel. “I’ve just got this.”

“Ah. And in that would be—what, exactly?”

“An apple. And a companion.” She observed the faint flicker of incomprehension on the old man’s forehead. “My diary,” she added. “From my sister, Shirin. She’s a terraforming engineer on Venus. She’s working with the change-clouds, to make the atmosphere breathable….”

“Now which of us is doing the wittering?” Corax shook the visible part of his head. “No, there’s nothing for it, I’m afraid. I can’t let you go now. You’ll have to stay here and wait for the flier. I’m afraid you’re going to be in rather a lot of hot water.”

“I know,” Yukimi said resignedly.

“You don’t seem to care very much. Is everything all right? I suppose it can’t be, or you wouldn’t have stowed away on an airship.”

“Can you get me home?”

“Undoubtedly. And in the meantime I can certainly see that you’re taken care of. There’s a catch, of course: you’ll have to put up with my inane ramblings until then. Do you think you can manage that? I can be something of a bore, when the mood takes me. It comes with age.”

Behind Corax, the cargo doors were closed. The loading ramps had retracted and now even larger doors—belonging to the Scaper—were sealing off Yukimi’s view of the airship.

“I suppose it’s too late now anyway,” Yukimi said.

SHE FOLLOWED CORAX’S stomping, wheezing suit down into the deeper levels of the Scaper. By the time they got anywhere near a window the airship was a distant, dwindling dot, turned the color of brass by the setting sun. Yukimi considered herself lucky now not to be stuck on it all the way to Milankovic. She was sure she could do without food and water for two days (not that it would be fun, even with the apple for rations) but it had never occurred to her that it might get seriously cold. But then, given that the airships had not been built for the convenience of stowaways, it was hardly surprising.

Yukimi was glad when Corax got out of the armor. At the back of her mind had been the worry that he was something other than fully human—she had, after all, only been able to see the top of his head—but apart from being scrawnier and older than almost anyone she could ever remember meeting, he was normal enough. Small by Martian standards—they were about the same height, and Yukimi hadn’t stopped growing. The only person that small Yukimi had ever met had been her aunt, the one who sent the snow globe, and she had been born on Earth, under the iron press of too much gravity.

Under the armor Corax had been wearing several layers of padded clothing, with many belts and clips, from which dangled an assortment of rattling, chinking tools.

“Why do you live out here?” she asked, as Corax prepared her some tea down in the Scaper’s galley.

“Someone has to. When big stuff like this goes wrong, who do you think fixes it? I’m the one who’s drawn the short straw.” He turned around, conveying two steaming mugs of tea. “Actually it’s really not that bad. I’m not one for the hustle and bustle of modern Martian civilization, so the cities don’t suit me. There are a lot like us, leftovers from the old days, when the place was emptier. We keep to the margins, try not to get in anyone’s way. Bit like this Scaper, really. As long as we don’t interfere, they let us be.”

“You live in the Scaper?”

“Most of the time.” He sat down opposite Yukimi, tapping a knuckle against the metal tabletop. “These things were made two hundred years ago, during the first flush of terraforming.”

“The table?”

“The Scaper. Built to last, and to self-repair. They were supposed to keep processing the atmosphere, sucking in soil and air, for as long as it took. A thousand years, maybe more. They were designed so that they’d keep functioning—keep looking after themselves, locked on the same program—even if the rest of human civilization crashed back to Earth. Their makers were thinking long-term, making plans for things they had no real expectation of ever living to see. A bit like cathedral builders, diligently laying down stones even though the cathedral might take lifetimes to finish.” He paused and smiled, years falling from his face, albeit only for an instant. “I don’t suppose you’ve ever seen a cathedral, have you, Yukimi?”

“Have you?”

“Once or twice.”

“The Scapers were a bad idea,” Yukimi said. “That’s what my sister told me. A relic from history. The wrong way to do things.”

“Easy to say that now.” He drew a finger around the rim of his tea mug. “But it was a grand plan at the time. The grandest. At its peak, there were thousands of machines like this, crisscrossing Mars from pole to pole. It was a marvelous sight. Herds of iron buffalo. Engines of creation, forging a new world.”

“You saw them?”

He seemed to catch himself before answering. “No; I’d have to be quite impossibly old for that to be the case. But the reports were glorious. Your sister’s quite right. It was the wrong approach. But it was the only way we—they—could see at the time. So we mustn’t mock them for their mistakes. In two hundred years, someone will be just as quick to mock us for ours, if we’re not careful.”

“I still don’t see why you have to live out here.”

“I keep this Scaper from falling apart,” Corax explained. “Once upon a time the self-repair systems were adequate, but eventually even they stopped working properly. Now the Scaper has to be nursed, treated with kindness. She’s an old machine and she needs help to keep going.”

“Why?”

“There are people who care about such things. They live on Mars, but also elsewhere in the system. Rich sponsors, for the most part. With enough money that they can afford to sprinkle a little of it on vanity projects, like keeping this machine operational. Partly out of a sense of historical indebtedness, partly out of a cautionary attitude that we ought not to throw away something that worked, albeit imperfectly, and partly for the sheer pointless hell of it. It pleases them to keep this Scaper running, and the others still trundling around. It’s Martian history. We shouldn’t let it slip through our fingers.”

Yukimi had no idea who these people were, but even among her father’s friends there were individuals with—in her opinion—rather more money than sense. Like Uncle Otto with his expensive private sunjammer that he liked to take guests in for spins around Earth and the inner worlds. So she could believe it, at least provisionally.

“For them,” Corax went on, “it’s a form of art as much as anything else. And the cost really isn’t that much compared to some of the things they’re involved in. As for me—I’m just the man they hire to do the dirty work. They don’t even care who I am, as long as I get the stuff done. They arrange for the airships to drop off supplies and parts, as well as provisions for me. It’s been a pretty good life, actually. I get to see a lot of Mars and I don’t have to spend every waking hour keeping the Scaper running. The rest, it’s my own time to do as I please.”

Looking around the dingy confines of the galley, Yukimi couldn’t think of a worse place to spend a week, let alone a lifetime.

“So what do you do?” she asked politely. “When you’re not working?”

“A little industrial archaeology of my own, actually.” Corax put down his tea cup. “I need to make some calls, so people know where you are. They’re sending out a flier tomorrow anyway, so we should be able to get you back home before too long. Hopefully it won’t arrive until the afternoon. If there’s time, I’d like to show you something beforehand.”

“What?”

“Something no one else will ever see again,” Corax said. “At least, not for a little while.”

He made the calls and assured Yukimi that all would be well tomorrow. “I didn’t speak to your parents, but I understand they’ll be informed that you’re safe and sound. We can try and put you through later, if you’d like to talk?”

“No thanks,” Yukimi said. “Not now.”

“That doesn’t sound like someone in any great hurry to be reunited. Was everything all right at home?”

“No,” Yukimi said.

“And is it something you’d like to talk about?”

“Not really.” She would, actually. But not to Corax; not to this scraggy old man with tufts of white hair who lived alone in a giant, obsolete terraforming machine. He might not be an ogre, but he couldn’t possibly grasp what she was going through.

“So tell me about your sister, the one on Venus. You said she was involved in the terraforming program. Is she much older than you?”

“Six years,” Yukimi said. She meant Earth years, of course. A year on Mars was twice as long, but everyone still used Earth years when they were talking about how old they were. It got messy otherwise. “She left Mars when she was nineteen. I was thirteen.” She reached into her satchel and pulled out the companion. “This is the thing I was talking about, the diary. It was a present from Shirin.”

He moved to open the book. “Might I?”

“Go ahead.”

He touched the covers with his old man’s fingers, which were bony and yellow-nailed and sprouted white hairs in odd places. The companion came alive under his touch, blocks of text and illustration appearing on the revealed pages. The text was in an approximation of Yukimi’s handwriting, tinted a dark mauve, the pictures rendered in the form of woodcuts and stenciled drawings, and the entries were organized by date and theme, with punctilious cross-referencing.

Corax picked at the edge of the book with his fingernail. “I can’t turn to the next page.”

“That’s not how you do it. Haven’t you ever read a book before?”

He gave her a tolerant smile. “Not like this.”

Yukimi showed him the way. She touched her finger to the bottom right corner and dragged it sideways, so that the book revealed the next pair of pages. “That’s how you turn to the next page. If you want to turn ten pages, you use two fingers. Hundred pages, three fingers. And the same to go backward.”

“It seems very complicated.”

“It’s just like a diary. I tell it what I’ve been doing, or let it record things for me. Then it sorts it all out and makes me fill in the gaps.”

“Sounds horrendous,” Corax said, pulling a face as if he had just bitten into a lemon. “I was never very good at diary keeping.”

“It’s meant to be more than just a diary, though. Shirin had one as well—she bought it at the same time. She was leaving, so we wouldn’t be able to talk normally anymore because of the lag. I was sad because she’d always been my best friend, even though she was older than me. She said our companions would help us bridge the distance.”

“I’m not sure I understand.”

“We were both supposed to use our companions all the time. Make entries whenever we could. I would talk to my companion as if Shirin was there, and Shirin would talk to hers as if I was there. Then, every now and again, the companions would—I can’t remember the word.” Yukimi frowned. “Connect up. Exchange entries. So that my companion got better at copying Shirin and hers got better at copying me. And then if we kept on doing that, eventually it would be like having Shirin with me all the time, so that I could talk to her whenever I wanted. Even if Venus was on the other side of the sun. It wouldn’t be the same as Shirin—it wasn’t meant to replace her—but just make it so that we didn’t always feel apart.”

“It seems like a good idea,” Corax said.

“It wasn’t. We promised we’d keep talking to our companions, but Shirin didn’t. For a while, yes. But once she’d been away from Mars for a few months she stopped doing it. Every now and again, yes—but you could tell only because she was feeling bad about not doing it before.”

“I suppose she was busy.”

“We promised each other. I kept up my side of the promise. I still talk to Shirin. I still tell her everything. But because she doesn’t talk to me enough, my companion can’t pretend to be her.” Yukimi felt a wave of sadness slide over her. “I could have really used her lately.”

“It doesn’t mean she doesn’t love you. It just means she’s an adult with a lot of people making demands on her. Terraforming’s very important work. It requires great responsibility.”

“That’s what my parents keep saying.”

“It’s the truth. It always has been. The people who made the Scapers understood that, even if they didn’t get the technology quite right. It’s the same with—what they call them? Those things in the air, swirling around?”

“Change-clouds,” Yukimi said.

He nodded. “I see them sometimes at dusk. Just another machine, really. In a thousand years, there won’t seem much difference between them and this. But they make me feel very old. Even your book makes me feel like an old relic from prehistory.” He stood up, his knees creaking with the effort. “Speaking of recording devices, let me show you something.” He moved to one of the shelves and pushed aside some junk to expose an old-looking space helmet. He brought it back to the table, blowing the dust off it in the progress, coughing as he breathed some of it in, and set the helmet down before Yukimi.

“It looks ancient,” she said, trying hard not to show too much disappointment. It was scratched and dented and the white paint was coming off in places. There had once been colorful markings round the visor and crest, but they were mostly faded or rubbed away now. She could just make out the ghostly impressions where they had been.

“It is. Unquestionably. Older even than this Scaper. I know because I found it and…well.” He stroked the helmet lovingly, leaving dust tracks where his fingers had been. “There’s serious provenance here. It used to belong to someone very famous, before he went missing.”

“Who?”

“We’ll come to that tomorrow. In the meantime I thought it might be of interest. The helmet’s still in good nick—built to last. I had to swap out the power cells, but other than that I’ve done nothing to it. Do you want to try it on?”

She didn’t, really, but it seemed rude to say so. She gave an encouraging nod. Corax picked up the helmet again and shuffled around the table until he was behind her. He lowered it down gently, until the cushioned rim was resting on her shoulders. She could still breathe perfectly normally because the helmet was open at the bottom. “It smells moldy,” she said.

“Like its owner. But watch this. I’m going to activate the head-up display playback, using the external controls.” He pressed some studs on the outside of the helmet and Yukimi heard soft clicks and beeps inside.

Then everything changed.

She was still looking at Corax, still inside the galley. But overlaid on that was a transparent view of something else entirely. It was a landscape, a Martian landscape, moving slowly, rocking side to side as if someone was walking. They were coming to the edge of something, a sharp drop in the terrain. The pace slowed as the edge came nearer, and then the point of view dipped, so that Yukimi was looking down, down at her chest-pack, which looked ridiculously old and clunky, down at her heavy, dust-stained boots, down at the Martian soil, and the point where—just beyond her toes—it fell savagely away.

“The edge of Valles Marineris,” Corax told her. “The deepest canyon on Mars. It’s a long way down, isn’t it?”

Yukimi agreed. Even though she was sitting down, she still felt a twinge of vertigo.

“You can still go there, but it’s not the same,” Corax went on. “Mostly filled with water now—and it’ll only get deeper as the sea levels keep rising. Where I’m standing—where you’re standing—is now a chain of domed resort hotels. They’ll tear down the domes when the atmosphere gets thick enough to breathe, but they won’t tear down the hotels.” He paused. “Not that I’m complaining, or arguing against the terraforming program. It’ll be marvelous to see boats sailing across Martian seas, under Martian skies. To see people walking around under that sky without needing suits or domes to keep them alive. To see Earth in the morning light. We’ll have gained something incredible. But we’ll have lost something as well. I just think we should be careful not to lose sight of that.”

“We could always go back,” Yukimi said. “If we didn’t like the new Mars.”

“No,” Corax said. “That we wouldn’t be able to do. Not even if we wanted it more than anything in the world. Because once we’ve touched a world, it stays touched.” He reached over and turned off the head-up display. “Now. Shall we think about eating?”

IN THE MORNING they left the Scaper, traveling out in a small, four-wheeled buggy that came down from a ramp in the great machine’s belly. “Just a little sightseeing trip,” Corax said, evidently detecting Yukimi’s anxiety about not being back when the flier—scheduled for the afternoon—came to collect her. They were snug and warm in the buggy’s pressurized cabin, Yukimi wearing the same clothes as the day before, Corax in the same outfit he had been wearing under the armor, which—for reasons not yet clear to Yukimi—he had stowed in the buggy’s rear storage compartment.

“Will the Scaper be all right without you aboard?” Yukimi asked, as they powered out of its shadow, bouncing over small rocks and ridges.

“She’ll take care of herself for a few hours, don’t you worry.”

An awkward question pushed itself to the front of Yukimi’s mind. “Will you always be the one in charge of it?”

Corax steered the buggy around a crater before answering. “Until the people who pay for my upkeep decide otherwise.” He glanced sideways, a cockeyed grin on his face. “Why? You think old Corax’s getting too old for the job?”

“I don’t know,” she answered truthfully. “How old are you, exactly?”

“How old do you reckon?”

“Older than my aunt, and I’m not sure how old she is. She’s from Earth as well.”

“Did I say I was from Earth?”

“You mentioned cathedrals,” Yukimi said.

“I could have been there as a tourist.”

“But you weren’t.”

“No,” he said eventually. “I wasn’t. Here I’m the tourist.”

They drove on, crossing kilometers of Martian terrain. Most of the time Corax didn’t have his hands on the controls, the buggy navigating by itself. Yukimi saw tire tracks in the soil and guessed that Corax had come this way before, maybe within the last few days. As the route wound its way around obstacles, the Scaper became little more than a dark, chimney-backed hump on the horizon, seemingly fixed in place. And then even the dark hump was gone.

The ground began to dip down. Ahead, reflecting back the sun like a sheet of polished metal, was what appeared to be a large lake or even a small sea. It had a complicated, meandering shoreline. Yukimi could not see the far side, even with the buggy raised high above sea level. She did her best to memorize the shape of the lake, the way it would look from above, so that she could find it on a map. That was hard, though, so she took out the companion and opened the covers so that it recorded the view through the buggy’s forward window.

“You want to know where we are?” Corax asked.

Yukimi nodded.

“Approaching Crowe’s Landing. You ever hear of it?”

“I don’t think so.”

“Doesn’t surprise me. It’s been a ghost town for decades; I’d be surprised if it’s on any of the recent maps. It certainly won’t be on them for much longer.”

“Why not?”

“Because it’ll soon be under water.”

Corax took control of the buggy again as it completed its descent to the edge of the lake, following a zigzagging path down the sloping terrain. As they neared the water, Yukimi made out a series of sketchy shapes floating just beneath the surface: pale rectangles and circles, some of them deeper than others, and reaching a considerable distance from the shore. They looked like the shapes on some weird game board. They were, she realized, the roofs and walls of submerged buildings.

“THIS WAS A town?”

Corax nodded. “Way back when. Mars is on its second wave of history now—maybe even its third. I remember when Shalbatana was nothing, just a weather station that wasn’t even manned half the time. Crowe’s Landing was a major settlement. Not the main one, but one of the four or five largest colonies on the surface. Yes, we called them colonies back then. It was a different time. A different age.” Slowly, he guided the buggy into the waters, picking his way down what must have been a thoroughfare between two rows of buildings. With some apprehension, Yukimi watched the water lap over the tops of the wheels, and then against the side of the cabin. “It’s all right,” Corax said. “She’s fully submersible. I’ve taken her a full kilometer out, but we’re not going anywhere so far today.”

They were driving along a hard surface, so even though the buggy’s wheels were underwater, they didn’t stir up much material. The water was clear enough that Yukimi could see for tens of meters in all directions. As the road sloped down, the sea gradually closed over the cockpit bubble and it was almost possible to believe that they were just driving through a normal, albeit strangely unpopulated, district of Shalbatana City. The buildings were rectangles, cylinders, and domes, all with small black windows and circular, airlock style doors set out from the main structure in rounded porches. There must never have been a bubble around Crowe’s Landing, so the buildings would have been the inhabitants’ only protection from the atmosphere. Yukimi guessed that there were tunnels linking them together, sunk under the road level. Even the newer communities like Shalbatana—and it was strange now to think of her hometown as “new”—had underground tunnels, maintained to provide emergency shelter and communication should something untoward happen to the bubble. Yukimi had been down into them during school field trips.

She wasn’t alone—she was in the cabin with Corax—but there was still something spooky about driving slowly through this deserted colony. She wished Corax hadn’t called it a ghost town, and while she understood that he hadn’t meant that the place was literally haunted, she couldn’t turn her imagination off. As the light wavered down from the overlying sea, she kept seeing faces appear in the windows, brief and spectral like paper cutouts held there for a moment. Once they turned a corner and passed another kind of buggy, left parked there as if its owners had only just abandoned it. But it was a very old-fashioned looking buggy, and the symbols painted on its side reminded her of the faded markings on the old space helmet.

Eventually Corax brought the buggy to a halt.

“We’re here,” he said grandly. “The objective. You see that building to our right, the one shaped like an old-fashioned hat box?”

“Yes,” Yukimi said dubiously.

“It’s still airtight, unlike most of the others. Because of that, it’s watertight as well. And the airlock’s still functioning—there’s just enough power in the mechanism for another cycle. Do you see where I’m headed?”

“Not really.”

“Crowe’s Landing is almost gone now, and in a hundred years it’ll be completely forgotten. The seas will rise, Mars will be greened. A whole new civilization will bloom and prosper. You’ll be part of that, Yukimi—when you’re older. You’ll see wonderful things and live to tell your grandchildren of the way it used to be, before the change-clouds finished their work.” He smiled. “I envy you. I’ve lived a very long time—the drugs weren’t always the best, but at least I had a ready supply—but my time’s coming to an end now and you’ll outlive me by centuries, if luck’s on your side.”

Yukimi thought of all the things in her life that were not the way she wanted. “I don’t think it is.”

“I’m not sure. That airship could have carried on to Milankovic, and then where would you be?”

“Hm,” she said, remaining to be convinced.

“I had an idea,” Corax said. “Not long after I found this place and this building. Mars is changing now and the seas will rise. But they won’t stay that way forever. One day—a thousand or ten thousand years from now, maybe more—the seas will shrink again. People will have other worlds to green by then, and maybe they’ll let Mars return to its primal state. Whatever happens, Crowe’s Landing will eventually come out of the waters. And that building will still be there. Still airtight.”

“You can’t be sure.”

“It’s a fair bet. Stronger odds of surviving than anything left on the surface, with everything that’s to come. Soon there’ll be woods and forests out there, and where there aren’t woods and forests there’ll be cities and people. There’ll be weather and storms and history. But none of that will reach down here. This building’s as close to a time capsule as we’re going to find. Which is why we’ve come.” He tapped a few commands into the buggy’s console and stood up creakily. “That helmet I found? It used to belong to Crowe, one of the very first explorers.”

“Can you be sure?”

“Reasonably. As I said, it’s got provenance.” He paused. “I’m going to put the helmet in there. It’s a piece of the past, a memento of the way Mars used to be. Not just a chunk of metal and plastic but a historical document, a living record. I only played back a tiny part of what’s stored in that helmet. That old fool captured thousands of hours, and that’s not including all the log entries he made, all the thoughts he put down for posterity. An old man’s ramblings…but maybe it’ll be of interest to someone. And it’ll all still be inside that helmet when they find it again.”

Yukimi had trouble thinking much further in the future than her seventeenth birthday, when she would receive the golden gateway into the aug. Everything was a blank after that. Centuries, thousands of years—what difference did it make?

“Will anyone understand it?”

“They may have to work at it,” Corax allowed. “But that’s what historians and archaeologists do. And I was thinking: while we’re at it, why don’t we give them something else to puzzle over, in addition to the helmet?”

Yukimi thought for a moment. “You mean my companion?”

“Your thoughts and observations aren’t any less valid than Corax’s. You’ll miss your diary, of course, and maybe you’ll have some explaining to do to your sister when she finds out what happened to it—assuming you tell her, of course. But in the meantime, think what you’ll have done. You’ll have sent a message to the future. A gift from the past to a Martian civilization that doesn’t even exist yet. No matter what happens, you’ll have made your mark.”

“No one’s interested in what I have to say,” Yukimi said.

“Don’t put yourself down. Look, there’s still time to make another entry. Tell them how you got here. Tell them how you feel today, tell them what made you run away from home yesterday. Be angry. Be sad. Get it out of your system.”

“I’ve got to go back to it later.”

“Believe me, this will help. When everything seems like it couldn’t get any worse, you’ll always be able to tell yourself: I did this one brilliant thing, this one brilliant thing that no one else has ever or will ever do. And that makes me special.”

She thought about the companion. It had been a gift from Shirin and—for all that it was dog-eared, and not the smartest in the world—she had treated it with fondness. It reminded her of her older sister. It reminded her of the good times they had spent together, before Shirin bored of childhood games and started looking to the skies, dreaming of worlds to make anew.

But had Shirin really cared? It had been easy for her to promise to keep her side of the bargain, before she said good-bye. Yukimi sometimes wondered if her sister had given her more than a moment’s thought except for the times when her conscience prickled her into sending a message.

“I cared,” Yukimi said to herself. “Even if you didn’t.”

She still had the companion in her hands from when she had shown it the lake.

“You want a moment to yourself?” Corax asked.

Yukimi nodded.

SHE STAYED IN the submerged buggy while he took the helmet and the companion into the airtight building. He went out in the underwater armor, a monster born anew. But when he had taken a few paces away from the buggy and turned back to wave, Yukimi waved back. She couldn’t see his face, but she knew it was Corax inside now, and while the armor was still monstrous, it was no longer frightening. Corax had been kind to her, and on some level he had seemed to understand what she was going through.

She watched him enter the building via the porch airlock. Some bubbles erupted out of the dark mouth of the door, and then there was nothing. She didn’t think it would take him long to place the helmet and the companion, especially if he already knew his way around the building.

The buggy started moving.

It was sudden, purposeful activity, not the result of the brakes being loose or some underwater current stirring it into motion. It began to turn, steering back the way they had come. This wasn’t right. Yukimi looked despairingly at the console, with its many controls. She didn’t know which one to hit. There was a red panel, lit up as if it was some kind of emergency stop. She whacked it with her palm and then when there was no response she whacked it again and again. She grabbed hold of the steering joystick Corax had been using and tried yanking it left and right. But nothing she did had any effect on the buggy’s progress. It was already climbing out of the lake, the water beginning to drain off the top of the canopy as it pushed into air. “Stop!” she shouted. “Corax isn’t back yet!”

But either the buggy was too stupid to realize what was happening or Corax had programmed it to ignore her.

Soon it was out of the lake. Once the ripples had settled, Yukimi could see the outline of Crowe’s Landing exactly as it had been before. Nothing had changed. Except now Corax was down there, inside the armor, inside the watertight building.

She remembered him punching commands into the buggy before he had stood up. Had he been telling it to return to the Scaper after a set interval with Yukimi was still aboard?

Numb, but knowing there was nothing she could do, she sat in silence for the rest of the journey.

THE FLIER CAME not long after the buggy climbed back into the Scaper’s belly. She was sitting alone in the galley, barely able to speak, when she heard footsteps echoing down the long metal corridors from the landing bay. Eventually two adults came into the galley. One was a young-looking man carrying a heavy bag. The other was her father, looking worried and gray. She braced herself for a stinging reproof, but instead her father rushed to Yukimi and hugged her. “I’m sorry,” he said. “We didn’t realize.”

When she could find the words she asked, “Am I in trouble?”

“No,” her father said soothingly. “I am. But you’re not. Not now. Not ever.” He hugged her again, as if he couldn’t quite believe he had her in his arms, that it wasn’t a dream.

“Where’s the old guy?” asked the other man.

“I presume you mean Corax?” Yukimi asked.

“Yeah, Corax.” The young-looking man set his bag down on the table and began unloading it. “I’m his replacement. That’s why the flier was scheduled, so I could take over from him. The sponsors were worried he was getting a little too old for this kind of thing.”

“Corax isn’t coming back,” Yukimi said.

The man looked impatient with her, as if she wasn’t showing sufficient deference. “What do you mean, not coming back? What happened to him? Where is he?”

She looked him straight in the face, daring him to dismiss what she was about to say. “That’s between me and Corax.”

“Are you all right, Yukimi?” her father asked gently.

“I’m fine,” she said. Which, for the moment at least, was the truth. She was sad for Corax, sad that she wouldn’t see him again. But whatever he had done, he must have planned on doing it long before she took her airship ride. That he had shared it with her, that he had allowed her to place the companion in the time capsule, and to record her thoughts before doing so—her angry, bitter, wounded thoughts—was a privilege and a secret she would always carry with her. And whatever happened next, however hard it got with her family, she would have the knowledge that she had participated in something wonderful and unique, something no one else would know about until the seas retreated, on some impossibly distant day in the future of Mars, her Mars.

The flier took off, leaving the other man alone on the Scaper. Her father let Yukimi sit by the window as the flier accelerated back toward Shalbatana City. Nose pressed to glass, she studied the wheeling, rushing landscape for the lake where Crowe’s Landing used to be. She saw a few patches of water, some vehicle tracks, and some of them looked vaguely familiar. But from up above, with an entirely different perspective, she couldn’t be certain.

“Shirin’s coming back from Venus,” her father said, breaking the long silence.

“Oh,” Yukimi answered.

“She says she’s sorry she hasn’t been in touch as often as she’d have liked.”

“I’m sorry as well.”

“She means it, Yukimi. I saw how upset she was.”

Yukimi didn’t answer immediately. She watched the ground hurtle by, thinking of Corax in his armor, the old man and the Martian sea. Then she reached out and took her father’s hand in hers. “It’ll be good to see Shirin,” she said.