Manifold: Space

by Stephen Baxter

  "Cut to the chase, Sally," he said gently.

  She paused for effect, like a kid doing a magic trick. Then she said, "Nuclear pulse propulsion. We think that's the answer, Malenfant. A series of microexplosions – fusion of deuterium and helium-3 probably – set off behind a pusher plate."

  He nodded. "I've heard of this. Project Orion, back in the 1960s. Like putting a firecracker under a tin can."

  She shaded her eyes from the Sun's glare. "Well, they proved the concept, back then. The Air Force actually ran a couple of test flights, in 1959 and 1960, with conventional explosives. And it's got the great advantage that we could put it together quickly."

  "Let's do it."

  "Of course we'd need access to helium-3."

  "NASDA will supply that. I have some contacts... Maybe we should look at assembly in lunar orbit. How are you going to keep me alive?"

  She smiled. "The ISS is still up there. I figure we can cannibalize a module for you. Have you decided what you want to call your ship?"

  "The Commodore Perry," he said without hesitation.

  "Uh-huh. Who –?"

  "Perry was the guy who, in 1853, took the U.S. Navy to Japan and demanded they open up to international trade. Appropriate given the nature of my mission, don't you think?"

  "It's your ship." She glanced about. "Anyhow, what are you doing out here?"

  He nodded at the shuttle exhibit. "They've got my old EMU in there, on display. I'm negotiating to get it back."

  "EMU?"

  "My EVA mobility unit. My old pressure suit." He patted his gut, which was trim. "I figure I can still get inside it. I can't live with those modern Jap designs full of pond scum. And I want a maneuvering unit..."

  She was looking at him oddly, as if still unable to believe he was serious.

  "Not ours," Xenia whispered. "Nothing to do with Bruno."

  Suddenly Maura found it difficult to breathe. This is it, she thought. This unprepossessing blanket: the first indubitably alien artifact, here in our Solar System. Who put the blanket there? What was its purpose? Why was it so crudely buried?

  A robot arm reached forward from the probe, laden with sensors and a sample-grabbing claw. She wished that was her hand, that she could reach out too, and stroke that shining, unfamiliar material.

  But the claw was driven by science, not curiosity; it passed over the blanket itself and dug a shallow groove into the regolith that lay over it, sampling the material.

  Within a few minutes the results of the probe's analysis were coming in, and she could hear the speculation begin in Bootstrap's back rooms.

  "These are fines, and they are ilmenite-rich. About forty percent, compared to twenty percent in the raw regolith." "And the agglutinate has been crushed." "It's as if it has been beneficiated. It's just what we'd do." "Not like this. So energy-intensive..."

  She understood some of this. Ilmenite was a mineral – a compound of iron, titanium, and oxygen – that was common in long-exposed regolith on airless bodies like the Moon and the asteroids. Its importance was that it was a key source of volatiles: light and exotic compounds implanted there over billions of years by the solar wind, the thin, endless stream of particles that fled from the Sun. But ilmenite was difficult to concentrate, extract, and process; the best mining techniques the lunar Japanese had thought up were energy-intensive and relied on a lot of heavy-duty, unreliable equipment.

  "I knew it!" somebody cried. "There's no helium-3 in the processed stuff! None at all!" "None to the limits of the sensors, you mean." "Sure, but –" "You mean they're processing the asteroids for helium-3? Is that all?"

  Maura felt oddly disappointed. If the Gaijin were after helium-3, did that mean they used fusion processes similar to – perhaps no more advanced than – those already known to humans? And if so, they can't be so smart – can they?

  In her ears, the speculation raged on.

  "I mean, how dumb can these guys be? Helium-3 is scarce in asteroid regolith because you're so far from the Sun, which implants it. The Moon is a lot richer. If they came in a couple of astronomical units – " "They could just buy all they want from the Japanese."

  Laughter.

  "But maybe they can't come in any closer. Maybe they need, I don't know, the cold and the dark." "Maybe they are scared of us. You thought about that?"

  "They aren't so dumb. You see any rock crushers and solar furnaces here? That's what we'd have to use to get as efficient an extraction process. Think about that blanket, man. It has to be nanotech."

  She understood what that meant too: There was no brute force here, no great ugly machines for grinding and crushing and baking as humans might have deployed, nothing but a simple and subtle reworking of the regolith at a molecular, or even atomic, level.

  "That blanket must be digging its way into the asteroid grain by grain, picking out the ilmenite and bleeding the helium-3. Incredible." "Hey, you're right. Maybe it's extending itself as it goes. The ragged edge –" "It might eat its way right through that damn asteroid." "Or else wrap the whole thing up like a Thanksgiving turkey..." "We got to get a sample."

  "Bruno knows that..."

  Nanotechnology: something, at last, beyond the human. Something other. She shivered.

  But now there was something new, at the corner of her vision, something that shouldered its way over the horizon. It was glittering, very bright against the dark sky. Huge.

  It was as if a second Sun had risen above the grimy shoulder of Ellis. But this was no Sun.

  The prattling, remote voices fell silent.

  It was perhaps a kilometer long, and wrought in silver. There was a bulky main section, a smoothly curved cylinder with a mess of silvery ropes trailing behind. Dodecahedral forms – perhaps two or three meters across, silvered and anonymous – clung to the tentacles. There were hundreds of them, Maura saw. Thousands. Like insects, beetles.

  A ship. Suddenly she remembered why they were here: not to inspect samples of regolith, not to pick at cute nanotechnological toys. They were here to make contact.

  And this was it. She imagined history's view swiveling, legions of scholars in the halls of an unknown future inspecting this key moment in human destiny.

  She found she had to force herself to take a breath.

  The ship was immense, panning out of her view, cutting the sky in half. Its lower rim brushed the asteroid's surface, and plasma sparkled.

  The Bootstrap voices in her ear buzzed. "My God, it's beautiful." "It looks like a flower." "It must be a Bussard ramjet. That's an electromagnetic scoop –" "It's so beautiful, a flower-ship..." "Yeah. But you couldn't travel between the stars in a piece of junk like that!"

  Now those shining beetles drifted away from the ropes. They skimmed across space toward the Bruno. Were these dodecahedra individual Gaijin? What was their intention?

  Silver ropes descended like a net across her point of view now, tangling up the Bruno, until the view was crisscrossed with silver threads. The threads seemed to tauten. To cries of alarm from the insect voices at Bootstrap's mission control, the probe was hauled backward, and its gentle grip on the asteroid was loosened, tethers and pitons flying free in a slow flurry of sparkling dust.

  The brief glimpse of the Gaijin ship was lost. Stars and diamond-sharp Sun wheeled, occluded by dust specks and silver ropes.

  Maura felt her heart beat fast, as if she herself were in danger. She longed for the Bruno to burst free of its restraints and flee from these grasping Gaijin, running all the way back to Earth. But that was impossible. In fact, she knew, the Bruno was designed to be captured, even dissected; it contained cultural artifacts, samples of technology, attempts to communicate based on simple diagrams and prime-number codes. Hello. We are your new neighbors. Come over for a drink, let's get to know each other...

  But this did not feel like a welcoming embrace, a contact of equals. It felt like capture. Maura made a stern effort to sit still, not to struggle against silver ropes that were hundreds of millions of kilometers
away.

  Chapter 5

  Saddle Point

  The Commodore Perry was assembled in lunar orbit.

  The fuel pellets were constructed at Edo, on the Moon, by Nishizaki Heavy Industries, and hauled up to orbit by a fleet of tugs. Major components like the pusher plate and the fuel magazine frame were manufactured on Earth, by Boeing. The components were lifted off Earth by European and Japanese boosters, Ariane 12s and H-VIIIs.

  After decades in orbit the old International Space Station module had a scuffed, lived-in look. When the salvage crew had moved in the air had been foul and the walls covered with a scummy algae, and it had taken a lot of renovation to render it habitable again.

  The various components of the Perry were plastered with sponsors' logos. That didn't matter a damn to Malenfant; he knew most of his paintwork would be scoured off in a few months anyhow. But he made sure that the Stars and Stripes was large, and visible.

  Malenfant prepared himself for the trip.

  In her cramped office at JSC, Brind challenged him, one last time. She felt, obscurely, that it was her duty.

  "Malenfant, this is ridiculous. We know a lot more about the Gaijin now. We have the results returned by the probe –"

  "The Bruno."

  "Yes. The glimpses of the beautiful flower-ship. Fascinating."

  "But that was two years ago," Malenfant growled. "Two years! The Gaijin still won't respond to our signals. And we aren't even going back. The government shut down Frank Paulis's operation after that one shot. National security, international protocols..."

  She shrugged.

  "Exactly," he snapped. "You shrug. People have lost interest. We've got the attention span of mayflies. Just because the Gaijin haven't come storming into the inner system in flying saucers –"

  "Don't you think that's a good point? The Gaijin aren't doing us any harm. We're over the shock of learning that we aren't alone. What's the big deal? We can deal with them in the future, when we're ready. When they are ready."

  "No. Colonizing the Solar System is going to take centuries, minimum. The Gaijin are playing a long game. And we have to get into the game before it's too late. Before we're cut out, forever."

  "What do you think their ultimate intentions are?"

  "I don't know. Maybe they want to dismantle the rocky planets. Maybe take apart the Sun. What would you do?"

  Oddly, in her mundane, cluttered office, her security badge dangling at her neck, she found herself shivering.

  The Perry looped through an elliptical two-hour orbit around the Moon. On the lunar surface, the lights of the spreading Japanese colonies and helium-3 mines glittered.

  The completed ship was a stack of components fifty meters long. At its base was a massive, reinforced pusher plate, mounted on a shock-absorbing mechanism of springs and crushable aluminum posts. The main body of the craft was a cluster of fuel magazines. Big superconducting hoops encircled the whole stack.

  Now pellets of helium-3 and deuterium were fired out of the back of the craft, behind the pusher plate. They formed a target the size of a full stop. A bank of carbon dioxide lasers fired converging beams at the target.

  There was a fusion pulse, lasting 250 nanoseconds. And then another, and another.

  Three hundred microexplosions each second hurled energy against the pusher plate. Slowly, ponderously, the craft was driven forward.

  From Earth, the new Moon was made brilliant by fusion fire.

  The acceleration of the craft was low, just a few percent of gravity. But it was able to sustain that thrust for a long time – years, in fact – and once the Perry had escaped lunar orbit, its velocity mounted inexorably.

  Within, Reid Malenfant settled down to the routines of long-duration spaceflight.

  His hab module was a shoebox, big enough for him to stand up straight. He drenched it with light from metal halide lamps, hot white light like sunlight, to keep the blues away. The walls were racks that held recovery units, designed for easy replacement. There were wires and cables and ducts running along the corners of the hab module and across the walls. A robot spider called Charlotte ran along the wires, cleaning and sucking dust out of the air. Despite his best efforts, the whole place was soon messy and cluttered, like an overused utility room. Gear was scattered everywhere, stuck to the floor and walls and ceiling with straps and Velcro. If he brushed against a wall he could cause an eruption of gear, of pens and softscreens and clipboards and data discs and equipment components, and food cans and toothpaste and socks.

  Much of the key equipment was of Russian design – the recycling systems, for instance. He had big generators called Elektrons that could produce oxygen from water distilled from his urine. Drinking water was recovered from humidity in the air. There was a system of scrubbers called Vozdukh that removed carbon dioxide from the air. He had a backup oxygen generator system based on the use of "candles" – big cylinders containing a chemical called lithium perchlorate that, when heated, gave off oxygen. He had emergency oxygen masks that worked on the same principle. And so on.

  It was all crude and clunky, but – unlike the fancier systems American engineers had developed for the space station – it had been proven, over decades, actually to work in space, and to be capable of being repaired when it broke down. Still, Malenfant had brought along two of most things, and an extensive tool kit.

  Malenfant's first task, every day, was to swab down the walls of his hab module with disinfected wipes. In zero gravity microorganisms tended to flourish, surviving on free-floating water droplets in the air. It took long, dull hours.

  When he was done with his swabbing, it was exercise time. Malenfant pounded at a treadmill bolted to a bracket in the middle of the habitation module. After an hour Malenfant would find pools of sweat clinging to his chest. Malenfant had to put in at least two hours of hard physical exercise every day.

  On it went. Boring a hole in the sky, the old astronauts had called it, the dogged cosmonauts on Salyut and Mir. Looking at stars, pissing in jars. To hell with that. At least he was going someplace, unlike those guys.

  He communicated with his controllers on Earth and Moon using a ten-watt optical laser, which gave him a data rate of twenty kilobits a second. He followed the newscasts that were sent up to him, which he picked up with his big, semitransparent main antenna.

  As the months wore on, interest in his mission faded. Something else he'd expected. Nobody followed his progress but a few Gaijin obsessives – including Nemoto, he hoped, who had, deploying her shadowy, vast resources, helped assemble the funding for this one-shot mission – not that she ever made her interest known.

  Sometimes, even during his routine comms passes, there was nobody to man the other end of the link.

  He didn't care. After all they couldn't call him back, however bored they were.

  While he worked his treadmill, his only distraction was a small round observation port set in the pressure hull near him, and so he stared into that. To Malenfant's naked eye, the Perry was alone in space. Earth and Moon were reduced to starlike points of light. Only the diminishing Sun still showed a disc.

  The sense of isolation was extraordinary. Exhilarating.

  He had a sleeping nook called a kayutka, a Russian word. It contained a sleeping bag strapped to the wall. When he slept he kept the kayutka curtained off, for an illusory sense of privacy and safety. He kept his most personal gear here, particularly a small animated image of Emma, a few seconds of her laughing on a private NASA beach close to the Cape.

  He woke up to a smell of sweat, or sometimes antifreeze if the coolant pipes were leaking, or sometimes just mustiness – like a library, or a wine cellar.

  Brind had tried another tack. "You're seventy-two years old, Malenfant."

  "Yeah, but seventy-two isn't so exceptional nowadays. And I'm a damn fit seventy-two."

  "It's pretty old to be enduring a many-year space flight."

  "Maybe. But I've been following lifespan-extending practices for decades
. I eat a low-fat, low-calorie diet. I'm being treated with a protein called coenzyme Q10, which inhibits aging at the cellular level. I'm taking other enzymes to maintain the functionality of my nervous system. I've already had many of my bones and joints rebuilt with biocomposite enhancements. Before the mission I'm going to have extensive heart bypass surgery. I'm taking drugs targeted at preventing the buildup of deposits of amyloid fibrils, proteins that could cause Alzheimer's –"

  "Jesus, Malenfant. You're a kind of gray cyborg, aren't you? You're really determined."

  "Look, microgravity is actually a pretty forgiving environment for an old man."

  "Until you want to return to a full Earth gravity."

  "Well, maybe I don't."

  After two hundred and sixty days, halfway into the mission, the fusion pulse engine shut down. The tiny acceleration faded, and Malenfant's residual sense of up and down disappeared. Oddly, he felt queasy; a new bout of space adaptation syndrome floored him for four hours.

  Meanwhile, the Perry fired its nitrogen tet and hydrazine reaction control thrusters, and turned head over heels. It was time to begin the long deceleration to the solar focus.

  The Perry, at peak velocity now, was travelling at around seven million meters per second. That amounted to 2 percent of the speed of light. At such speeds, the big superconducting hoops came into their own. They set up a plasma shield forward of the craft, which sheltered it from the thin interstellar hydrogen it ran into. This turnaround maneuver was actually the most dangerous part of the trajectory, when the plasma field needed some smart handling to keep it facing ahead at all times.

  The Perry was by far the fastest man-made object ever launched, and so – Malenfant figured, logically – he had become the fastest human. Not that anyone back home gave a damn.

  That suited him. It clarified the mind.

  Beyond the windows now there was only blackness falling between Malenfant and the stars. At five hundred astronomical units from the Sun, he was far beyond the last of the planets; even Pluto reached only some forty astronomical units. His only companions out here were the enigmatic ice moons of the Kuiper Belt, fragments of rock and ice left undisturbed since the birth of the Sun, each of them surrounded by an emptiness wider than all the inner Solar System. Farther beyond lay the Oort cloud, the shadowy shell of deep-space comets; but the Oort's inner border, at some thirty thousand astronomical units, was beyond even the reach of this attenuated mission.