Déjà Doomed

by Edward M. Lerner

  “The self-healing wall coating that harvests and distributes power.”

  “It does that, yes, and also communications functions, but I am beginning to suspect this material is much more. But let me start with the larger-scale equipment. Much critical equipment must be large because the Titans are large. Consoles are sized for the hands and eyes that use them. Other equipment, I believe, is macroscale for robustness, the better to accommodate large current flows or high-radiation environments. Yet other equipment might have been large so that Titan hands and bots could install them, or make repairs to them, faster than the smart coating could grow. In constructing their lunar base, the Titans might have needed certain capabilities immediately.

  “As for the smart coating, samples have been much analyzed. There are the nanites that extrude various types of carbon nanotubes. There are scattered, tiny reservoirs of scavenged materials, most of it carbon, waiting to be put to use. Mostly, there are seemingly random tangles of the carbon nanotubes themselves. Some nanotubes, as we first learned, convert light to electricity, in the manner of silicon photovoltaic cells. Some distribute power. Some appear to serve as a mechanical framework on which more-complex structures can grow. But many of these nanotubes form transistors, of which the only application that has been identified is sensors. To orient toward the brightest light. To sense gaps to grow into and fill. But there is so much more that vast numbers of transistors could do.”

  “Uh-huh,” Marcus said. “Pretty much anything. But I’ve also seen the reports from Base Putin. From what I recall there isn’t any large-scale structure to the nanotech scrapings we sent them, nothing to suggest complicated applications. No processors. No memory arrays. Nothing like that.”

  “You forget. I believe the Titans did much with neural nets.” Ekatrina seemed to discover her hands, and be at a loss what to do with them. “Sensing. Learning. Adapting ….”

  Tiny neural nets, if that’s what they were. Far denser than meshes of biological neurons. And the aggregate mass of the coating that lined the ship’s hull and internal bulkheads? “Jesus,” he said. “I see what you mean. We could be living inside a gigantic brain. And every time we scrape off a patch ….”

  She raised an eyebrow. “That brain likes us even less.”

  “Jesus,” he repeated.

  The walls have ears, went an old adage. Only suppose walls in the lunar tunnels, and throughout this ship, were more than ears? Alien brains lining the walls—and then sensing, growing, tapping ancient memories, responding to “intruders”—would explain so much. Such as why robot swarms had eventually attacked. Such as displays in the Titan control room, long after human fuel cells had been removed, coming alive to gloat. Such as compromising Yevgeny’s shuttle, and through that penetration transmitting to the Hammer the order to obliterate Earth ….

  “Is this ship intelligent?” he mused aloud. “Is it aware? Alive? Can we somehow reason with it?”

  “Has it tried to reason with us? No! Only to kill us! We act only to defend ourselves.”

  “And Earth. And humanity.”

  “And all that,” Ekatrina agreed.

  “One thing bothers me. Okay, more than one. But explain this. We keep scouring and scraping coating from the walls, and the coating keeps returning. How?”

  “Us,” she said. “You, me, all of us, breathing. We each exhale about a kilo of carbon dioxide every day. That, I believe, is the primary carbon source for the continuing growth.”

  Like the paint back in their underground lair. As he should have remembered.

  Inside Marcus’s pocket, a folded datasheet chimed. He took the call on speaker. “What’s up?”

  Yevgeny said, “We are approaching the halfway mark.”

  Meaning a short return to free fall, and the onset of a gentle deceleration phase. Meaning they were almost there. Almost to the Hammer.

  “I’ll join you in a few minutes,” Marcus responded. And to Ekatrina, he added. “Find some way to bring at least one reactor back online. However this ship might feel about it.”

  * * *

  A half kilometer below, the Hammer was a slowly turning chunk of dead, Sun-blasted metal. There was no hint whatever of alien propulsion or controls, no sign this asteroid had ever before been visited. If anything here could deflect the Hammer from its doomsday course, Yevgeny saw no evidence of it. Ground-penetrating radar, when he tried searching with that … didn’t. There was far too much metal below for the GPR to be useful.

  “A few minutes” proved to be optimistic, but eventually Marcus arrived on the bridge. They had by then been more than an hour in orbit, and that long in free fall. Marcus braced himself in the hatchway. Taking in the desolate view through the canopy, he looked demoralized. Reactor repair must not be going well. He sighed. “Any suggestions where to set us down?”

  Yevgeny shook his head.

  Yun, loosely strapped into the copilot seat, was fixated on his datasheet. The main image on that comp, a 3-D wire-frame outline of the Hammer, was obvious enough. So, too, the representation of Rescue One’s orbit about the asteroid’s waist. The scrolling columns of numbers displayed in a second window were another matter.

  “Yun?” Marcus prompted.

  Yun waved a hand dismissively.

  “Yun,” Marcus repeated. “What are you doing?”

  Not lifting his head, Yun said, “My datasheet is linked to our laser altimeter and stereo camera. I am making a detailed topographic model of the Hammer.”

  “Why?” Yevgeny asked.

  “Because we lack proper equipment.” At last, Yun glanced up. “This survey should be performed by two satellites in a shared orbit, one ahead of the other, linked by laser beam. There was no time before we set out to prepare such apparatus.”

  “My turn,” Marcus said. “Why?”

  Yun warmed to his subject. “Very minor dynamic changes in the separation between probes as they orbit would reveal variations in local gravity. Those, in turn, would allow me to calculate with precision the local variations in mass distribution. Earth scientists use satellite pairs to determine such things as the mass of glaciers, and hence their thickness. But with a detailed enough topographic map, and by assuming a uniform density, I hope to approximate the Hammer’s detailed mass distribution.”

  “Why?” Yevgeny and Marcus asked in unison.

  “A theory. I’ll need a few orbits to be certain.” Yun scratched his head. “Even at this low altitude, the Hammer’s comparatively tiny mass means it will take us about eighty minutes per orbit. In about ten, we will we finish our first.”

  Time they did not have to spare. Yevgeny caught Marcus’s eye. “We can fly around the rock and complete this survey in a fraction of the time. If, that is, we can spare the power to make more fuel.”

  Marcus tipped his head. “I’ll check in with Ilya and Katya and get back to you on that. Quite unrelated, I could use some coffee. Yevgeny, do you care to join me? And can I bring you anything, Yun?”

  “Green tea, please,” Yun said absentmindedly.

  “This near in,” Yevgeny said, “and the Hammer being of such an irregular shape, I have my doubts how predictable, or even how stable, this orbit is. I would not be comfortable away from the controls. But I will take ice water, please.” It might be in his head, but already the ship felt hot.

  “Stay regardless,” Yun said, “because I need you to make changes in our orbit.” He pointed out the canopy. “Once we complete this first orbit, move us a kilometer or so closer to that end.”

  Marcus left and returned with drink bulbs, and left again to see what he could contribute to addressing their engine-room problems. And Yevgeny … waited.

  After completing the first orbit, Yevgeny shifted them, per Yun’s directions, to a new orbit along the Hammer’s longest axis. Minutes into the second orbit, Marcus called with the go-ahead to continue using their limited
aitch-two and oh-two. And after completing that second circuit, Yevgeny began a third, this one toward the opposite, somewhat more bulbous, end of the Hammer’s longest axis.

  Several minutes into this third orbit, Yun nodded vigorously, approvingly.

  “What?” Yevgeny asked.

  “Perhaps what I expected.” Yun pointed sunward. “I cannot yet be sure. Can we have a look from one more angle? I would like to see that end.”

  “Because you expect to see …?”

  “Unless I see it, it won’t matter. You might as well wait.”

  Scientists! Yevgeny thought. But did as Yun wished.

  With another round of drink bulbs in hand, looking less grim (progress in the engine room?), Marcus returned to the bridge. “What have we learned?”

  Yevgeny shrugged.

  Yun, eyes twinkling even more than usual, accepted his drink bulb of tea. Took a long swallow. Pointed out the canopy. “That is our goal.”

  “Care to explain?” Marcus asked.

  Yun downed another long swig. (A dramatic pause? Perhaps.) “Do you see the deep crater there? Yes? Project down its center and, as best I can determine, the line passes through the Hammer’s center of mass.” He grinned. “If I had an apparatus for giving the Hammer a good, hard shove, down at the bottom of that pit is exactly where I would place it.”

  Chapter 52

  Never mind the steady twenty-degree (Celsius) readout on Marcus’s HUD, he was sweating. It might have been the memory of how hot it had become inside Rescue One. It might have been in reaction to the intense sunlight streaming through the airlock’s open outer hatch, or the black spot on his helmet visor to obscure the freakily large solar disk. Or the eye-wateringly bright reflection glints off the Hammer as it spun by a scant fifty meters below. Or dwelling on the maneuver he was about to attempt.

  And it did nothing for Marcus’s nerves to be wrestling with a bulky, massive, hard-shell suit, and not the lightweight, flexible, formfitting—and all too readily torn—counterpressure suit that had become almost like his second skin.

  If Brad and Nikolay had worn hard-shell suits, they might still be alive.

  “Testing, testing,” Yun radioed. In his own hard-shell suit, he stood beside Marcus in the airlock. Having guided them to the Hammer, Yun had cheerfully declared, he had rendered himself expendable.

  Well, Marcus thought, someone has to accompany me. “Yun, you’re loud and clear.”

  “And I read you both,” Yevgeny radioed from the bridge. “Ready when you are.”

  “I am ready now,” Yun said.

  “Let’s do it,” Marcus agreed.

  “Acceleration in five,” Yevgeny radioed. “Four. Three ….”

  Deftly, Yevgeny matched angular velocities with the spinning asteroid, hovering over the flat patch they had chosen, with frequent but random-seeming flashes of the thrusters. “This is burning a lot of fuel, gentlemen.”

  “Right.” Marcus flicked a switch as he flung their improvised grapple. The switch started a countdown timer.

  The grapple drifted down until (with a clang sadly unable to cross vacuum) its electromagnet, activated by the timer, latched onto the metallic surface. The battery should hold the grapple in place for two hours. Long enough, he hoped, to determine if this flight had been a fool’s errand.

  Marcus gathered up slack rope, and gave the grapple an experimental tug. It held. He switched off his boot magnets, unclipped his safety tether from the airlock, and slipped the carabiner around the grapple’s line. Yun did the same.

  They drifted out of the airlock.

  Even as they climbed hand over hand toward the surface, the asteroid’s spin reeled in line, varying their angle of approach. Marcus was soaked with sweat before the asteroid came into reach. He swung his body around, presenting his feet to the oncoming surface. He landed with a jolt, his left knee buckling, its hard-shell joint smacking into the ground. The shock ran up his body, snapping his teeth together.

  But his suit did not crack, nor did his teeth. And the grapple held. And the asteroid’s spin did not hurl him back into space. All in all, a minor success. Marcus switched on his boot magnets and clomped aside.

  Moments later, with more grace, Yun joined him on the ground.

  Marcus pivoted until he spotted the ship. Foregoing active, fuel-gulping maneuvers, it had, from his perspective, already gone halfway to the eerily close horizon. “Rescue One, we’re down,” he radioed.

  “Copy that,” Yevgeny replied.

  Would anyone else hear this? The day Marcus had met Valerie, back when she worked for the Green Bank Observatory, she had boasted that their big dish could eavesdrop on a cell-phone call on Titan. The Hammer was a lot closer to Earth than Titan. That particular radio telescope no longer stood, but Arecibo’s dish was bigger, and the Chinese had since built a radio telescope that was larger still. And, although it seemed like something from another life, it was not all that long ago that he had helped deploy a large antenna array on the lunar farside.

  Then again, Titan was not two-trillion-plus metric tons of dense metal, its every nearby surface reflecting and interfering with their transmissions. That Val had picked Titan for her brag seemed, in retrospect, an ironic coincidence.

  Yevgeny came back on comms. “This orbit will bring the ship overhead again in about seventy minutes. If by then you haven’t completed your initial inspection”—and Marcus had estimated half that time should suffice—“I’ll start burning fuel and come back around every ten or so minutes.”

  “Copy that.” And Marcus stood, watching, until Rescue One sank beneath the nearby horizon. “Okay, Yun. Onward.”

  From a few paces away, Yun waved acknowledgement.

  Gravity on this asteroid was all but nonexistent. So, tethered together, only one man moving at a time, probing at each step for a flat spot where a boot’s magnet would grip, Marcus and Yun shuffled toward the suspect crater. Along the way, Yun kept stopping to shoot landscapes and starscapes with a datasheet camera. The single celestial object Marcus yearned to see was Earth. It would be among the brightest lights in the sky—

  Except that the Hammer was in their way. Shitty symbolism.

  During Yun’s third photography stop, Marcus noticed a baseball-sized rock. He leaned over and picked it up. “I could throw this rock clear off the Hammer, right? Not put it into orbit, and have it come around and hit me in the back of the head.”

  Yun turned. In the bright sunlight, their visors were fully darkened; Marcus could not see Yun’s face. That did not keep Marcus from imagining the other’s lips silently moving as he committed physics and math in his head.

  “The Hammer is not a sphere,” Yun said, “but let that go. I estimate we have walked to within two kilometers of the spin axis. If the Hammer were concentrated in a sphere of that radius, the escape velocity would be about … twelve meters per second. The true escape velocity at this spot will be well less than that. Oh, and a small fraction of a meter per second lower still if you throw in the direction of the asteroid’s spin.”

  Twelve meters per second. About … twenty-seven miles an hour. “In my Little League days, I pitched fastballs at better than sixty miles per hour. My son, Simon, can do seventy.”

  “Were either of you wearing a hard-shell suit?”

  Not deigning to answer, Marcus pegged the rock and watched it recede. “I dub thee Asteroid Simon.”

  “An asteroid must be at least a meter across. You only made a meteoroid, and meteoroids are not given names.”

  “Just hurry up, please.”

  Approaching the Hammer’s spin axis, Marcus’s stomach and inner ears began doing backflips. And not in sync. He had kept a hand on his gas pistol since setting out on their trek; now, on the verge of the destination crater, his grip became white-knuckled.

  Did Earth’s salvation lie in its depths? Or would their la
st hopes be dashed?

  * * *

  After a cautious descent into the deep crater, their undulating shadows preceding them, they found a hole at the very bottom. Circling the shaft—about three meters across, as round and uniform as a manhole—they encountered a ladder, its rungs spaced a good meter apart.

  “The Titans were here,” Yun said. “Shall we go down for a look?”

  Marcus gathered up most of their tether. “Hold this.” He planted his feet, boot tips kissing the rim, and started to lean. “Please don’t drop me.”

  “And have to haul you back up? Don’t worry.”

  Tipping forward until his ankles screamed, and leaning from side to side, Marcus peered into the shaft. It ran straight and deep. A round column, perhaps a half meter across, ran up the very center of the shaft, with two spindly girders rising alongside it. He got the sense of a significant-sized chamber at the bottom of the passageway. Imagining swarms of Titan robots excavating it, he shivered.

  “Pull me back,” Marcus said, and Yun reeled him in. “Have a look yourself.”

  With Yun steeply inclined over the shaft, Marcus asked, “What do you think?”

  “Almost certainly, we are looking at a mass driver. An electromagnetic catapult.”

  “Meaning?”

  “Meaning, Captain, that we have located the Hammer’s propulsion system.”

  Chapter 53

  For a while, in a long overdue change to the mission’s fortunes, everything went right.

  —An explosives-tipped harpoon embedded itself in the Hammer, and Yevgeny reeled the ship to a safe docking point just outside the critical crater.

  —Ilya activated the fission reactor, which kept the ship’s battery bank topped off.

  —The two Russian men and Yun descended into the Hammer for an initial survey of whatever the Titans had built down there.

  —Marcus scraped and sanded clean great swaths of engine-room bulkheads without evoking any overt response.