Existence

by David Brin

  Tor glimpsed her partner up at the crater’s rim, directing robots that trimmed and foam-packed all but the most valuable salvaged parts for a long voyage, pulled Earthward by a light-sail freighter. Gavin had asked to work as far as possible from the “creepy stuff”—the musty habitat zone down below in the asteroid’s heart, that once held breathable air and liquid water.

  “I know we’ve got to explore all that,” he told her. “Just give me some time to get used to the idea.”

  How could Tor refuse a reasonable request, made without sarcasm? And so, she quashed her own urgent wish—to drop everything and rush back to those crumbling tunnels, digging around blasted airlocks and collapsed chambers, excavating a secret that lay buried for at least fifty million years.

  We may become the most famous grave robbers since Heinrich Schliemann or Howard Carter. For that, Tor supposed she could wait a bit.

  Some of the cutting drones were having a rough time removing a collapsed construction derrick, so Tor hop-floated closer, counting on ape-instincts to swing her prosthetic arms from one twisted girder to another, till at last she reached a good vantage point. The asteroid’s frail gravity tugged her mechanical legs down and around. Tor took hold of the derrick with one of the grippers that served her better than mere feet.

  “Drone K, go twelve meters left, then shine your beam down-forty, east-sixty. Drone R, go fifty meters in that direction”—she pointed carefully—“and shine down forty-five, west-thirty.”

  It took some minutes—using radar, lidar, and stereoscopic imagery—to map out the problem the drones were having, a tangle of wreckage with treasure on the other side. Not only baby probes but apparently a controller unit, responsible for building them! That could be the real prize, buried under a knotted snarl of cables and debris.

  Here an organic human brain—evolved in primal thickets—seemed especially handy. Using tricks of parallel image processing that went back to the Eocene, Tor picked out a passage of least resistance, faster than the Warren Kimbel’s mainframe could.

  “Take this route…” She click-mapped for the drones. “Start cutting here … and here … and—”

  A sharp glare filled the cavity, spilling hard-edge shadows away from every metal strut. Pain flared and Tor cringed as her faceplate belatedly darkened. Organic eyes might have been blinded. Even her cyborg implants had trouble compensating.

  The corner of her percept flared a diagnosis that sent chills racing down her spine. Coherent monochromatic reflections. A high-powered laser.

  A laser? Who the hell is firing…?

  Suppressing fear, her first thought was a cutter-drone malfunctioning. She started to utter the general shut-down command, when the war alarm blared instead!

  A weapon, then, commented some calm corner of her mind.

  As quickly as it struck, the brilliant light vanished, leaving her in almost-pitch blackness, with just the distant sun illuminating the exposed crater rim.

  “Gavin!” she started to shout. “Watch out for—”

  A sharp vocal cry interrupted.

  “Tor! I’m under attack.”

  Dry mouth, she swallowed hard.

  “Gavin … give specifics!”

  Her racing heart was original equipment. Human-organic 1.0, pounding like a stampede. Even faster when her partner replied.

  “I … I’m in a crevice—a slit in the rock. What’s left of me. Tor, they sliced off my arm!”

  They? She wanted to scream. Who—or what—is “they”?

  Instead of shrill panic squeaks, Tor somehow managed to sound like a commander.

  “Are your seals intact? Your core—” Crouching where there had been a stark shadow moments ago, she prayed the girder still lay between her body and the shooter.

  “Fine, but it smarts! And the arm flew away. Even if I make it out of here, my spare sucks. It’ll take weeks to grow a new—”

  “Never mind that!” Tor interrupted to stop Gavin from babbling. Get him focused. “Have you got a direction? Can your drones do a pinpoint?”

  “Negative. Three of them are chopped to bits. I sent the rest to cover. Maybe Warren—”

  Cripes. That reminded Tor. If a foe had taken out the ship …

  “Warren Kimbel, status!”

  There followed a long, agonizing pause—maybe three seconds—while Tor imagined a collapse of all luck or hope.

  Then came the voice she needed to hear.

  “I am undamaged, Captain Povlov. I was blocked from direct line to the aggressor by the asteroid’s bulk. I am now withdrawing all sensitive arrays, radiators, and service drones, except the one that’s relaying this signal. It is using a pop-out antenna.”

  “Good! Initiate war-danger protocols.”

  “Protocols engaged. Tracking and weapons coming online. I am plotting a course to come get both of you.”

  Tor would have bitten her lower lip, if she still had one, making a hard choice.

  “Better not move, just yet. That beam was damn powerful. Gavin and I are safe for now—”

  “Hey, speak for yourself!” her young partner interrupted. “You wouldn’t say that if an organo-boy had his arm chopped off!”

  “—but we’ll be screwed if any harm comes to the ship.”

  That shut Gavin’s mouth. Good. His position was worse than hers. He shouldn’t radiate any more than he had to.

  “Warren, did you get drone telemetry to analyze the beam?”

  “Enough for preliminary appraisal, Captain. From the kill-wattage, duration, and color, I give eighty-five percent probability that we were attacked by a FACR.”

  “Shit!”

  Across the broad asteroid belt, littered with broken wreckage of long-ago alien machines, only one kind was known to still be active. Faction-Allied Competition Removers—an awkward name, but the acronym stuck, because it was easily mispronounced into a curse.

  A couple of decades ago, less than a year after Gerald Livingstone recovered the first of the space-fomites, there had come the Night of the Lasers, when observers on Earth stared skyward in amazement, watching the distant sky crisscross with deadly beams. That same day, all over the Earth, hundreds of buried crystals detonated bits of themselves, in order to draw attention and perhaps get themselves dug up. All this desperation happened just after world media carried the Havana Artifact’s formal sales pitch, offering humanity its deal for a certain kind of immortality.

  Why did all of that occur on the same fateful day? It took some time to put all the pieces together and grasp what happened—the reason why that broadcast had such violent effects. And apparently it’s not over.

  “Warren,” she said. “Maybe it’s no coincidence that we were attacked just after you orbited behind the rock.”

  There was no immediate response, as the ship’s mind pondered this possibility. Tor couldn’t help feeling the brief, modern satisfaction that came from thinking of something quicker than an ai did.

  “If I grasp your point, Captain, you are suggesting that the FACR is afraid of me. More afraid than I should be, of him?”

  “That could explain why it waited till you were out of sight, before shooting at Gavin and me. If it figures you’re too strong to challenge … well, maybe you can come get us, after all.”

  “Amen,” murmured Gavin. Then, before Tor could admonish, he lapsed back into radio silence.

  “Unless it was the machine’s intent to lure us into drawing exactly that conclusion,” the ship-brain mused. “And there may be another reason for me to remain where I am, for now.”

  A soft click informed Tor that Warren was switching to strong encryption.

  “I have just confirmed a two-way channel to the ISF vessel Abu Abdullah Muhammad ibn Battuta. They are only three light-minutes away.”

  Well at last, a stroke of luck! Suddenly Tor felt less alone.

  She quelled her enthusiasm. Even using its fusion-ion engines, the big, well-armed cruiser would have to maneuver for weeks in order to match orbits and come h
ere physically. Still, that crew might be able to help in other ways. She checked encryption again, then asked the Warren Kimbel—

  “Can ibn Battuta bring sensors to bear?”

  “That ship has excellent arrays, Tor. As of last update, they were swinging sensors to focus on the region in question—where the killer beam came from—a stony debris field orbiting this asteroid, roughly five kilometers from here, twenty north by forty spinward. They will need some minutes to aim their instruments. And then there is the time lag. Please attend patiently.”

  “Ask them not to use active radar,” Tor suggested. “I’d rather the FACR didn’t know about them yet.”

  “I have transmitted your request. Perhaps it will reach them in time to forestall such beams. Please attend patiently.”

  This time Tor kept silent. Minutes passed and she glanced at the starscape wheeling slowly overhead. Earth and the sun weren’t in view, but she could make out Mars, shining pale ocher in the direction of Ophiuchus, without any twinkle. And Tor realized something unpleasant—that she had better start taking into account the asteroid’s ten-hour rotational “day.”

  North by spinward…, she pondered. Roughly that way … She couldn’t make out any glimmers from the “stony debris field,” which probably consisted of carbonaceous stuff, light-drinking and unreflective. A good hiding place. Much better than hers, in fact. A quick percept calculation confirmed her fear.

  At the rate we’re rotating, this here girder won’t protect me much longer.

  Looking around, she saw several better refuges, including the abyss below, where baby starships lay stillborn and forever silent. Unfortunately, it would take too many seconds to hop drift over to any of those places. During which she’d be a sitting duck.

  Why in space would a FACR want to shoot us, anyway?

  The battle devices were still a mystery. For the most part, they had kept quiet, ever since the Night of the Lasers. In all of the years that followed, while humanity cautiously nosed outward from the homeworld and began probing the edges of the belt, she could recall only a couple of dozen occasions when the deadly relic machines were observed firing their deadly rays … mostly to destroy some glittering crystal—or one another, but occasionally blasting at Earthling vessels with deadly precision, and for no apparent reason.

  Armed ships, sent to investigate, never found the shooters. Despite big rewards, offered for anyone who captured a FACR dead or alive, they were always gone—or well hidden—before humans arrived.

  We finally figured out they must be leftovers from the final battle that tore through our solar system long ago. Survivors who made a devil’s bargain with the interstellar crystals. A battle machine would help one of the crystal fomite factions to win, by eliminating its competition. In return, that faction would repay the favor, once it took over the local civilization. In exchange for its help, the FACR might win a role in the new order.

  Biologists claimed to see clear parallels in the way some natural diseases did their deadly business, with viruses and bacteria paving the way for each other. One exo-sociologist wagered that the Last Machine War—ravaging Sol System tens of millions of years ago—must have been triggered by the arrival of crystal message capsules. They likely infected some of the more ancient mechanical probes, swaying them with persuasive offers of immortality and propagation. This theory might explain the Night of the Lasers.

  When it seemed likely that the Havana Artifact was about to win over humanity, uncontested, all the other fomites had to gamble everything to draw our attention—either sacrificing bits of themselves to detonate come-get-me signals underground, or emitting risky here-I-am flashes as they drifted overhead. But these FACR devices were out here waiting, after eons, to fight for one crystal lineage or another. To help one faction to get heard … or to blast others and keep them from making their pitch.

  It all made a kind of Darwinian sense … or so the best minds explained, reminding everyone that evolution had ferocious logic.

  But then, how can this one benefit by firing at us?

  Eyeing the rate of rotation, she knew another question was paramount.

  How am I gonna get out of here?

  It wouldn’t suffice to just sidle sideways around the ancient girder, which was narrow and perforated in the other direction. And Gavin’s situation was probably even worse. We’ve got to do something soon.

  “Warren. Has ibn Battuta scanned the debris field?”

  “Yes, Tor, with passive telescopes. Their results are inconclusive. They have mapped the component rocks and sand clouds and report half a dozen anomalies that might possibly be hiding the shooter. With active radar they might pinpoint the resonance of refined metal—”

  “Or else get confused by nickel-iron meteoritic material. Anyway, the instant they transmit active beams, the damned thing will realize we have an ally. It can shift position long before they get a return signal and are able to fire any kind of weapon. Six minutes light-turnaround is huge.”

  “I can find no fault with your reasoning. Then perhaps our main option remains for me to emerge from shadow and come get the two of you. As you say, the machine may be reticent to do battle with a foe my size.”

  “And what if we’re wrong? Suppose the damn thing fires at you?”

  “Then I will engage it in battle.”

  “You won’t get in the first shot. Or even the second.”

  “Agreed. In a worst-case scenario, I calculate that—with excellent marksmanship—the FACR could take out my primary weapon, then attack my main drive units. But I still might position myself with vernier thrusters, so that you and Gavin could make it aboard. Even if I am rendered helpless, my innermost radiation shelter should keep you safe until help arrives.”

  Another voice blurted out.

  “Screw that! I can shut down for a month or two. But Tor would starve or go crazy in that time!”

  She felt touched by her partner’s concern—the first time she recalled him ever talking that way.

  “Thanks, Gavin. But don’t transmit. That’s an order.”

  He went silent with a click … perhaps in time to keep the enemy from localizing him too accurately. Tor weighed her options.

  On the positive side, the ibn Battuta might be a powerful ally, if the distant cruiser managed to catch their foe by surprise with a radar beam, just once, getting a clear position fix that would be obsolete before the signal even returned. Double that light delay, and you’ve effectively rendered the ship’s mighty weapons useless.

  Then there was Warren Kimbel sitting much closer, but also much less formidable. And the Warren would need several minutes to emerge from the roid’s shadow, the whole time vulnerable to a first shot. Or several.

  She took census of the robotic salvage drones. A dozen or so were still in decent shape, down here with her. Or else near Gavin.

  And finally … there’s me.

  Tor didn’t much like the plan taking shape in her mind. Frankly, it too well reminded her of the desperate measures she took long ago, alongside the brave man that her ship was named after, aboard a doomed zeppelin.

  But I don’t see where there’s any other option.

  And timing is really going to be critical.

  Maybe I should have stayed home and remained a girl reporter.

  “Okay,” Tor said, with a glance at the encryption monitor. “Here’s what we’re gonna do.”

  THE LONELY SKY

  Lurker Challenge Number Four

  If you’ve been monitoring our TV, radio, and Internet—and the reason you haven’t answered is that you are studying us and have a noninterference policy, let’s say we understand the concept.

  * * *

  Examining more primitive species or cultures can seem to demand silence for a time, in order for observers not to interfere with the subject’s natural behavior. Your specific reason may be scientific detachment, or to let us enjoy our “innocence” a while longer, or perhaps because we are unusual in some rare or prec
ious way. Indeed, we can imagine many possible reasons you might give for keeping the flow of information going in just one direction—from us to you—and never the other way. Similar rationalizations are common among human observers.

  Of course, some of us might respond that it was cruel of you not to contact us during the murderous World Wars or perilous Cold War, when news of contact might have prodded us away from our near-brush with annihilation. Or that you should have warned us about the dangers of ecological degradation, or many other pitfalls. Or call it heartless to withhold advanced technologies that could help solve many of our problems, saving millions of lives.

  In fairness, some other humans would argue that we have won great dignity by doing it all by ourselves. They take pride in the fact that we show early signs of achieving maturity by our own hard efforts. If your reason for silence is to let us have this dignity, that might make sense …

  … so long as it isn’t simply an excuse, a rationalization, to cover more selfish motives.

  To interfere or not? It’s a moral and scientific quandary that you answer by silently watching, to see if we’ll solve our problems by ourselves. (Perhaps we are doing better than you expected?) Your reasons may even have great validity.

  Still, if you continue this policy, you cannot expect profound trust or gratitude when we finally overcome our hardships and emerge as star-faring adults without help. Oh, we’ll try to be friendly and fair. But your long silence will make it hard, at least at first, to be friends.

  We understand cold-blooded scientific detachment. But consider—the universe sometimes plays tricks on the mighty. In some distant age, our roles may be reversed. We hope you’ll understand if our future stance toward you is set by your past-and-present behavior toward us.

  75.

  LURKERS

  I am pondering her latest posted challenge—a tasty one that pierces closer to truth than some others—when sudden confusion erupts! Unaccustomed to abrupt news, our community of refugees stirs in a babble. Awaiter and Observer extend their sensors. They play back the sharp glitter of this attack … followed by a buzz and crackle of cipher-code as the humans confer urgently with their vessel.