HEART OF THE COMET

PART 1: BANNERS OF THE ANGELS

October 2061

He that leaveth nothing to chance
will do few things ill,
but he will do very few things.
— Halifax

CARL

Kato died first.
          He had been tending the construction mechs — robots that were deploying girders on the thick black dust that overlay the comet ice.
          From Carl's viewpoint, on a rise a kilometer away, Kato's suit was a blob of orange amid the hulking gray worker drones. There was no sound, in spite of the clouds of dust and gas that puffed outward near man and machines. Only a little static interfered with a Vivaldi that helped Carl concentrate on his work.
          Carl happened to be looking up, just before it happened. Not far from Kato, anchored near the north pole of the comet's solid core, eight spindly spires came together to form a pyramidal tower. At its peak nestled the microwave borer antenna, an upside-down cup. Kato worked a hundred meters away, oblivious to the furious power lancing into the ice nearby.
          Carl had often thought the borer looked like a grotesque, squatting spider. From the hole beneath it came regular gushes of superheated steam.
          As if patiently digging after prey, the spider spat invisible microwaves down the shaft in five-second bursts. Moments after each blast, an answering yellow-blue jet of heated gas shot up from the hole below, rushing out of the newly carved tunnel. The billowing steam jet struck deflector plates and parted into six plumes, fanning outward, safely missing the microwave pod.
          The borer had been doing that for days, patiently hammering tunnels into the comet core, using bolts of centimeter-wavelength electromagnetic waves, tuned to a frequency that would strip apart carbon dioxide molecules.
          Carl felt a faint tremor in his feet each time a bolt blazed forth. The horizon of ancient dark ice curved away in all directions. Outcroppings of pure clathrate snow here and there jutted out through thick layers of spongy dust. It was a scene of faded white against mottled browns and deep, light-absorbing black.
          Kato and his mechs worked near the microwave borer, drifting on tethers just above the surface. The core's feeble gravity was not enough to hold them down when they moved. Overhead, thin streamers of ionized, fluorescing gas swayed against hard black night, seeming to caress the Japanese spacer.
          Kato supervised as his steel-and-ceramic robot mechanicals did the dangerous work. He had his back to the spider.
          Carl was about to turn back to his own task. The borer chugged away methodically, turning ice to steam. Then one of the giant spider legs popped free in a silent puff of snow.
          Carl blinked. The microwave generator kept blasting away as the leg flew loose of its anchor, angling up, tilting the body. He did not have time to be horrified.
          The beam swept across Kato for only a second. That was enough. Carl saw Kato make a jerky turn as if to flee. Later, he realized that the movement must have been a final, agonized seizure.
          The beam blasted the ice below the man, sending luminous sheets of orange and yellow gas pouring into the blackness above, driving billows of dust. Vivaldi vanished under a roar of static.
          The invisible beam traced a lashing, searing path. It jittered, waved, then tilted further. Away from the horizon. Toward Carl.
          He fumbled for his control console, popped the safety cover, and repeatedly stabbed the countermand switch. His ears popped as the static storm cut off. Every mech and high-power device on this side of Halley Core shut down. The microwave finger ceased to write on the ice only a few score meters short of Carl.
          The spider began to collapse. Halley's ten-thousandth of a G was too weak to hold down a firing microwave generator, but without the upward kick of expanding gas and radiation pressure, the iceworld's own weak attraction asserted itself. The frame lurched and began its achingly slow fall.
          — What the hell you doin'? My power's out. —
          That would be Jeffers. Other voices babbled over the commline.
          "Mayday! Kato's hurt." Carl shot across dirty-gray ice. His impulse jets fired with a quick, deft certainty as he flew, unconsciously moving with the least wasted energy, the result of years of training. Crossing the rumpled face of Halley was like sailing adroitly over a frozen, dusty sea beneath a black sky.
          Againsi all hope, he tried calling to the figure in the orange spacesuit, splayed, face downward, on the gouged snowfield. "Kato...?"
          When he approached, Carl found something that did not resemble a man nearly so much as a blackened, distorted, badly roasted chicken.

          Umolanda was next.
          The timetable didn't leave much room to mourn Kato. A med team came down from the flagship, the Edmund Halley, to retrieve Kato's body, but then it was back to work.
          Carl had learned years before to work through unsettling news, accidents, foul-ups. Shrugging off a crewmate's death wasn't easy. He had liked Kato's energy, his quick humor and brassy confidence. Carl promised his friend's memory at least one good, thoroughly drunken memorial party.
          He and Jeffers fixed the spider, reanchoring the foot and reflexing the leg. Carl cut away the damaged portion. Jeffers held the oxygen feed while he slapped a spindly girder segment into the opening. At Carl's signal, the other spacer played the gas jet over the seams and the metal leaped to life, self-welding in a brilliant orange arc. They had the repair done before Kato's body was back on the Edmund.
          Umolanda came over the rim of Halley Core, pale blue jets driving her along the pole-to-pole cable. The easiest way to move around the irregular iceball was to clip onto the cable and fire suit jets, skimming a few meters above the surface. Magnetic anchors released automatically as you shot by, to minimize friction.
          Umolanda was in charge of interior work, shaping irregular gouges into orderly tunnels and rooms. She met Carl near the entrance to Shaft 3, a kilometer from the accident site. The piledriving spider labored away again on the horizon.
          — Pretty bad about Kato, — she sent.
          "Yeah." Carl grimaced at the grisly memory. "Nice guy, even if he did play those old junk movies on the 3D all the time."
          — At least it was quick. —
          He didn't have anything to say to that, didn't like talking a whole lot out here anyway. It just interfered with the job.
          Umolanda's liquid eyes studied him through a bubble helmet spattered with grime. The neck ring hid her cleft chin. He was surprised to see that this omission revealed her as an otherwise striking woman, her ebony skin stretched by high cheekbones into an artful, ironic cast. Funny, how he'd never noticed that.
          — Did you investigate the cause? —
          "I checked the area where the spider leg got loose," Carl answered. "Looked like a fault under it gave way."
          She nodded. — Not surprising. I've been finding hollows below, formed when radioactive decay warmed the ice long ago, as Halley formed. If some hot gas from the spider's digging worked its way back to the surface through one of those hollows, it could undermine the spider's anchor. —
          Carl squinted at the horizon, imagining the whole cometary head riddled with snaking tunnels. "Sounds about right."
          — Shouldn't the spider have cut off as soon as it lost focus? —
          "Right."
          — The switch? —
          "Damn safety cutoff was defective. Just didn't kick in," Carl said sourly.
          Her eyebrows knitted angrily. — More defective equipment! —
          "Yeah. Some bastard Earthside made a little extra on the overhead."
          — You've reported it? —
          "Sure. It's a long walk back for replacement parts, though." He smiled sardonically. There was a brief silence before Umolanda spoke again.
          — There will always be accidents. We lost people at Encke, too. —
          "That doesn't make it any easier."
          — No... I guess not. —
          "Anyway, Encke was a pussycat of a comet. Old. Sucked dry. Lots of nice safe rock." He scuffed the surface softly with a boot tip. Snow and black dust puffed at the slightest touch.
          She forced a grin. — Maybe all this ice is supposed to keep us alive over the long haul, but it's killing us in the short run. —
          Carl gestured toward three mechs which stood nearby, waiting for orders. Already the machines were pitted and grimy from Halley's primordial slush. "That's your team. Kato was shaping them up. But you might want to give 'em a once-over, anyway."

          — They look okay. — Umolanda whistled up the color-coded readout on the back of the nearest one and nodded. — Some luck here. The microwave beam didn't hit them. I'll take them down, put them to hollowing out Shaft Three. —
          She tethered the boxy, multiarmed robots and gracefully towed them to the tunnel entrance. Carl watched her get them safely aligned and disappear down the shaft, leading the mechs like a shepherd, though in fact the mechs were as smart as a ten-year-old at some things, and a lot more coordinated.
          He went on to check out more of the equipment that other crewmen were ferrying down from the Edmund. It was dull labor, but he had been working in the shafts for days and needed a break from the endless walls of rubble-seamed ice.
          Overhead, gauzy streamers wove a slow, stately dance. Halley's twin shimmering tails were like blue-green silks. They were fading now, months past the brief summer crisping that came for the comet every seventy-six years. But still the banners of dust and ions unfurled, gossamer traceries waving as if before a lazy breeze, the flags of vast angels.

         The expedition had elected to rendezvous with Halley's comet after its 2061 perihelion passage, when the streaking planetoid was well on its way outward again. Here, beyond the orbit of Mars, the sun's violent heating no longer boiled off the huge jets of water molecules, dust, and carbon dioxide that made Halley so spectacular during its short summer.
          But heat lingers. For months, as Halley swooped by the fierce, eroding sun, temperature waves had been diffusing down through the ice and rock, concentrating in volatile vaults and scattered clumps of rock. Now, even as the comet lofted back into the cool darkness of the outer solar system, there were still reservoirs of warmth inside.
          The gritty, dark potato shape was a frozen milkshake of water, carbon dioxide, hydrocarbons, and hydrogen cyanide, each snow subliming into vapor at a different temperature. Inevitably, in some spots, the seeping warmth melted or vaporized ices. These pockets lay waiting.
          Carl was partway through assembling a chemical filter system when he heard a sharp high cry on suitcomm.
          Then sudden, ominous silence.
          His wrist display winked yellow-blue, yellow-blue; Umolanda's code.
          Damn. Twice in one shift?
          "Umolanda!"
          No answer. He caught the polar cable and went hand over hand toward the mouth of Shaft 3.
          Mechs milled at a cave-in, digging at the slowly settling ice amid swirls of sparkling fog. No signal from Umolanda. He let the mechs work but popped pellet memories out of their backpacks to scan while he waited. It was soon apparent what had happened.
          Deep in the ice, the mechs had dutifully chipped away at the walls of the first vault. Umolanda controlled them with a remote, staying in the main tunnel for safety. The TV relay told her when to sequence the robots over to a new routine, when to touch up details, when to bore and blast. She hung tethered, and monitored the portable readout board, occasionally switching over to full servoed control of a mech, to do a particularly adroit bit of polishing.
          She had been working at the far end of what would soon be a storage bay when a mech struck a full-fledged boulder of dark native iron two meters across. Captain Cruz had asked them to watch out for usable resources. Umolanda put all three mechs to retrieving it. Under her guidance they slipped levers around the boulder and tried to pry it free. The sullen black chunk refused to budge.
          Umolanda had to come in close to inspect. Carl could envision the trouble: mechs were good, but often it was hard to see whether they were getting the best angle.
          Carl had a dark premonition. The boulder had been absorbing heat for weeks, letting it spread into a slush that lay immediately behind it, a pocket of confined carbon dioxide and methane. This frothy soup would be perched at its critical point, needing only a bit more temperature or a fraction less pressure to burst forth into the vapor phase.
          Oh for chrissakes, Umolanda don't...
          A mech slipped its levering rod around the boulder, penetrating into the reservoir of slush. Umolanda saw the robot lurch, recover. She told it to try again, and moved a little closer to observe.
          The mech was slow, gingerly. Its aluminum jacket was spattered and discolored from several days in the ice, but its readouts showed it was in perfect running order. Using as its pivot its own tether in the wall, it levered around the boulder, lunged — and the iron gobbet popped free.
          No!
          Release of pressure liberated the vaporization energy. The explosion drove the pry bar out of the mech's grip like a ramrod fired through the barrel of a cannon.
          Umolanda was two meters away. The lever buried itself in her belly.
          The pellet-memory readout terminated. Carl blinked away tears.
          He waited while the mechs cleared the way. There was really no need to hurry.

          Mission Commander Miguel Cruz called off operations for two full shifts. The setup crew had been working to the hilt for a week. Two deaths in one day implied that they were making errors from plain fatigue.
          Umolanda's accident had spewed forth a pearly fog for an hour as the inner lake of slush boiled out. Had anyone Earthside been watching through a strong telescope, they could have detected a slight brightening at the cometary head. It was a fleeting memorial. The blinding storm had driven her mechs out into the shaft, dislodged enough ice to bury her. Carl and the others were kept outside until it was too late to recover her and freeze her down slowly for possible medical work. Umolanda was lost.
          Carl came up on the last ferry. The mottled surface seemed to darken with distance: the cometary nucleus dwindled to a blackish dot swimming in a luminous orange-yellow cloud. Though the fuzzy haze of the coma was still visible with a small telescope from Earth, from near the head itself the shimmering curtains of ions were lacy, scarcely noticeable. Gas and grains of dust still steadily popped free of Halley's surface, making cargo piloting tricky. Most of the outgassing now came not from the sun's ebbing sting, but from the waste heat of humans.
          As the ferry pulled outward the twin tails — one of dust and the other of fluorescing ions — stretched away, foreshortened pale remnants of the glories that had enthralled Earth only two months ago. Ragged streamers forked out toward Jupiter's glowing pinpoint. Oblivious, Carl stretched back and dozed while the ferry rose to meet the Edmund.
          When they clanged into the lock, he peeled off his suit and coasted toward the murmuring gravity wheel at the bow. He climbed down one of the spoke ladders and stumbled out into the unfamiliar tug of one-eighth G, feeling bone-deep weariness descend with the coming of weight.
          Sleep, yes, he thought. Let it knit up whatever raveled sleeve he had left.
          Virginia came first, though. He hadn't seen her in ages.
          She was in her working module, of course, halfway around the wheel. She seldom left the thing nowadays. The door hissed aside. When he slipped into the spherical world of encasing memory shells there was an almost cathedral-like hush, a sense of presence and humming activity just beyond hearing. He sat down quietly next to her cantilevered chair, waiting until she could extract from interactive mode. Tapped into channels through a direct neural link and wrist servos, she scarcely moved. She had to know he was there, but she gave no sign.
          Her slim body occasionally fidgeted and jerked. Like a dog dreaming, he thought, and trying to run after imaginary rabbits.
          Her long, half-Polynesian features were pointed toward the banks of holographic displays suspended above her, and her eyes never even flicked to the side to see him. She gazed raptly at multiple scenes of movement, sliding masses of ever-flickering data, geometric diagrams that shifted and evolved, telling new tales.
          He waited as she worked through some indecipherable problem. Her long face momentarily tightened, then released as she leaped some hurdle. She had delicate, high cheekbones, too, like Umolanda. Like a third of the expedition's crew, the Percells, products of Simon Percell's program in genetic correcting of inherited diseases. Carl wondered idly if fineboned, aristocratic features were traits the DNA wizard had slipped in. It was possible; the man had been a genius. Carl's own face was broad and ordinary, though, and he had been "developed," as the antiseptic jargon had it, within a year of Virginia. So maybe Simon Percell had taken such care only with the women. Given the gaudy stories told about the man, he couldn't rule out the possibility.
          By anyone's definition, Virginia Kaninamanu Herbert was clearly a successful experiment. A Hawaiian mixture of Pacific breeds, she had a swift, quirky intelligence, deliciously unpredictable. There was restless energy to her eyes as they moved in quick, darting glances at the myriad welter before her. Below, her mouth was a study in quiet immersion, slightly pursed, thoughtful and pensive. She was not, he supposed, particularly attractive in the usual sense of the term; her long face gave her a rangy look. The serene almond smoothness of her skin offset this, but her forehead was broad, the mouth too ample, her chin was stubbed and not fulsomely rounded as fashion these days demanded.
          Carl didn't give a damn. There was a compressed verve in her, a hidden woman he longed to reach. Yet all the time he'd known her she had stayed inside her polite cocoon. She was friendly but little more. He was determined to change that.
          On the main screen, obliquely turned girders filled together in precise sockets. The frame froze. Done.
          Abruptly Virginia came alive, as though some fluid intelligence had returned from the labyrinths other machine counterpart. She stripped the wrist inputs. The white socket for her neural connector flashed briefly as the tap came off and she fluffed her hair into shape.
          "Carl! I hoped you'd wait for me to finish."
          "Looks important."
          "Oh, this?" She waved away the frames of data. "Just some cleanup work. Checking the simulations of docking and transfer, when we take everybody down. There'll be irregularities from random outgassing jets, and the slot boats will have to compensate. I was programming the smarter mechs for the job. We're ready now."
          "It'll be a while."
          "Well, a few more days... Oh, yes." She suddenly became subdued. "I heard."
          "Damn bad luck." His mouth twisted sourly.
          "Fatigue, I heard."
          "That too."
          She reached out and touched his arm tentatively. "There was nothing you could do."
          "Probably. Maybe I shouldn't have let her go down that hole right after Kato bought it. Thing like that, shakes you up, screws up your judgment. Makes accidents more likely."
          "You weren't senior to her."
          "Yeah, but —"
          "It's not your fault. If anything, it's the constraints we work under. This timetable —"
          "Yeah, I know."
          "Come on. I'll buy you some coffee."
          "Sleep's what I need."
          "No, you need talk. Some people contact."
          "Trading arcane jokes with that computer crowd of yours?" He grimaced. "I always come out sounding like a nerd."
          She flexed smoothly out of her console couch, taking advantage of the low gravity to curl and unwind in midair. "Not at all!" Something in her sudden, bouncy gaiety lifted his heart. "Blithe spirit, nerd thou never wert."
          "Mutilated Shelley! God, that's awful."
          "True, though. Come on. First round is on me."

SAUL

To most people the creature would seem hideous. Vaguely globular, specked with yellow and ocher spots and spiky prolusions all around, it had the sort of looks only a particularly indulgent mother could love.
          Or a stepfather, Saul Lintz thought.
          Millions of the tiny, ugly things darted about in the crowded confines of a single, glinting drop of saline water, beaded by surface tension into a high, arching meniscus on the glass microscope slide.
          Saul played the fiber optic controls until his magnifier zoomed in on a single cyanute. "There we are," he muttered softly. "You'll do as a test subject, my lad."
          He pressed a trigger and the cytology instrument took over following the tiny microbe, automatically tracking it wherever it swam within its little universe.
          The creature was a pulsing mass of tiny, rainbowed cilia that rippled faster than the eye could follow. But Saul knew the thing anyway, to its smallest part. He could imagine every molded, microscopic component, down past where the instrument could not go — to the level of acids and bases, of sugars and finely balanced lipid barriers.
          It darted to and fro amid the thousands of other rough, rippling cells, seeking what it needed to survive.
          Not unlike us, Saul thought. Only our search has brought us humans half a billion miles from home.
          He rubbed his eyes and bent forward in a habit from long-ago days, when one still occasionally peered through cold glass lenses instead of letting the machines do all the hard work. Relax, Saul told himself. There's no need to crane over the screen.
          Even here, in Edmund's slowly spinning gravity wheel, there wasn't enough of a pull to fight against. One had to keep loose, or expend enormous energy just to stay still.
          Only half of the screens and holo displays in the biology unit brimmed with light. In a dozen other dark faces Saul's own pale image was reflected... thick eyebrows above a generous nose, and lines that most people, on meeting him, guessed came of a lifetime spent smiling.
          Only those who knew Saul well — and they were few these days — understood the true source of those craggy indentations; a stoicism that warded off the pain of many, many losses.
          The creases stood out now as Saul's blue eyes narrowed in concentration. Delicately touching a hand controller, he brought a hollow sliver of metal down into the little ball of salty water on the microscope slide. On the main holo screen the image of the tiny needle seemed to loom like a javelin as computers guided it toward the chosen test subject.
          "Come on, meshugga," Saul muttered as the microbe tried to dart away. "Hold still for Papa."
          The cyanute was less than fifty microns across, so small and innocuous that its ancestors had lived peacefully in human bodies for millions of years of quiet symbiosis, until they were discovered only a generation or so ago. For Saul the little creature contained as many wonders as the huge comet commanding such attention outside.
          The main vision wall of the lab had been left tuned to a view of Halley, not as the comet looked now — a slowly ebbing cloud of banked fluorescence surrounding a six-mile chunk of dingy snow — but as it had been only months before, in all its brief glory, streaking past the sun at half the Earth's orbital distance, its ion tail flapping in the protonic breeze.
          They were well matched in beauty — the titanic, cosmic messenger that was to be their home for most of a century and the microscopic wonder that had made the sojourn possible. Still, it was no surprise that, of the two, Saul concentrated on the tiny living thing drifting in the little glob of water.
          After all, he had made it.
          Sh'ma Yisrael... he reminded himself. There is but one God — even though he should place his tools in our hands — tools to shape life and forge worlds. He is only stepping back to see what we will do with them.
          In Saul's line of work he found it wise to remember that, from time to time.
          When the needle had approached to within a cell's width of the subject, Saul spoke a word and triggered the test sequence. A small, indistinct puff disturbed the water near the needle's tip, where tiny traces of hydrogen cyanide solution spurted forth.
          No more than a scattering of molecules was involved, yet the tiny organism reacted nearly instantly. Its cilia erupted in a sudden spasm of activity and the creature sprang forward....
          Forward, toward the needle. It engulfed the tip, throbbing with seeming eagerness.
          So far, so good. Saul would have been surprised if it had behaved differently. The cyanutes had been thoroughly tested on Earth before the mission to Halley's Comet was approved. No factor was more important to the success and health of 410 brave men and women than these little creatures.
          Confident he was. But life — even specially gene-tailored life — had a way of changing when you least expected it. The survival of all those people depended on the tiny "nutes" working as planned. He had led the team that designed them, and he did not intend to allow any failures. There were more than enough ghosts already in his life. Miriam, the children, the land and people of his youth... and, of course, Simon Percell.
          Poor Simon. All too well he recalled how one mistake had ruined his friend's life and nearly everything he had worked to accomplish, Keep reminding me, Simon. Keep reminding me of the dangers of playing God.
          All the HCN was gone now, according to the displays, sucked up by the eager organism. Saul nodded in satisfaction. Every human being on this mission had millions of cyanutes living in his or her bloodstream and in the little alveoli air sacs that made up their lungs. This sample, taken at random from one of the crew, had just demonstrated that it would do its main job — sop up any trace of deadly, dissolved cyanide gas before the stuff could get near its host's red corpuscles. Another puff of dissolved gas proved its ability to gobble carbon monoxide before that chemical could bind to human hemoglobin.
          Saul touched off the next stage in the test. Minute traces of a new compound swirled into the saline bubble. This time the little microbe on the screen quickly withdrew from the needle, curling almost as if it had been stung. Cyanide and CO were fresh grazing to this creature, but human tissue factors appeared to be a definite no-no.
          Again, good news. The second test showed that the cyanute was totally disinclined to look on human cells as meat.
          So much for the basics. There were countless other things to check. Saul mentally ran down a list as he triggered the sequencer to begin the automatic phase of the test program.
          ... Self-limiting reproduction, benign acceptance by the human immune system, pH sensitivity, a voracious appetite for other potential cometary toxins...
          It wasn't so much a catalog of attributes as a litany of challenges met and conquered. Saul couldn't help feeling proud of his small team back on Earth, which had had to overcome prejudice, bureaucracy, and undisguised superstition to do this work. In the end, though, they had created a wonder — a new human symbiont.
          Cyanutes would be a permanent, benign part of every man and woman on the crew for the rest of their lives... and perhaps, he dared imagine, a part of the human animal from now on, like the intestinal flora that had always helped him digest his food and the mitochondria within his cells that burned sugars for him, converting them into usable energy.
          "Who can compare with thee, oh Lord..." he whispered wryly, teasing himself for his ineradicable corner of hubris. Saul had long ago concluded that he and God would have to be patient with each other. Perhaps the universe was not conveniently set up for either of them.
          He watched the test results unfold on the screen — all nominal, nearly perfect — until a soft squeak announced the opening of the bio-lab portal behind him.

          "So! We are poking away at our pets again, Saul? You just cannot leave them alone?"
          He didn't have to look up to know the voice of Akio Matsudo. "Hello 'Kio." He waved without turning around. "Just double-checking. And everything looks fine, thanks. Aren't they lovely critters?"
          He smiled as the spry, tall Japanese physician came alongside and made a sour look. The chief of Mission Life Sciences had never disguised his opinion of Saul's "critters." They were necessary — utterly vital to the success of their seventy-eight-year voyage. But poor Akio had never come to see their more aesthetic side.
          "Ugh," Matsudo commented. "Please do not remind me of the infestation even now swarming in my bodily fluids. Next time you wish to inject me with alien parasites —"
          "Symbionts," Saul corrected quickly.
          "— against which my body has no immune capability whatsoever — next time I will make the incision myself — from crotch to sternum!"
          Saul could only grin as Matsudo's serious mug broke and the man actually giggled. It was a "kee-kee-kee" sound that spacers had already mimicked into a sort of clarion call below decks. Akio frequently made such light jests about the traditions of ancient Japan.
          Perhaps it was similar to the way Saul dropped Yiddishisms into his speech now and then, although he had learned the language only a decade ago. It's a proper dialect for exiles, he thought.
          "What have you got there, 'Kio?" He pointed at a flimsy sheet in the other's hand.
          "Ah. Yess." Matsudo tended to slur his sibilants. "Even as we are speaking of immune systems, I have come to ask you to go through the stimulants inventory with me, Saul. I believe that it is time to release an attenuated disease into the life-support system."
          Saul winced. He never looked forward to this.
          "So soon? Are you sure? Four-fifths of the expedition is still frozen aboard the Sekanina and the other freighter tugs. All we have awake now are the Edmund crew and support staff."
          "Al! the more reason" Matsudo nodded. "Thirty spacers have been living together on this cramped ship for more than a year. Another forty have been out of the slots for two or more months, as we got closer to the comet. All of the colds and minor viruses they brought with them when they departed Earth have run their course by now.
          "I've done a parasite inventory, and have found that more than three-quarters of the ambient pathogenic organisms have already gone extinct! It is time to release a new challenge."
          Saul sighed. "You're the boss." Actually, the entire bio committee was supposed to pass on immune challenges. But reminding Akio would only offend him. The procedure was routine, anyway.
          Still, Saul's nose already itched in unhappy anticipation.
          He reached over to the bio-library console and punched out a rapid code. A page of data appeared in space before a black backdrop.
          Saul nodded at the glowing green lettering. "There is a lovely array of nasty bugs at your disposal, Doctor. With what plague do you wish to infect your patients? We have chicken pox. fox pox, attenuated measles...."
          "Nothing so drastic." Matsudo waved. "At least not so soon."
          "No? Well, then there's impetigo, athlete's foot..."
          "Amaterasu! Heaven forfend, Saul! In this dampness? Before the comet-tunnel habitats have been set up and the big dehumidifiers are working? You know how the navy feels about fungus aboard a spaceship. Cruz would have our —"
          He stopped abruptly and grinned lopsidedly. "Ha ha. Very funny, Saul. You are pulling my leg, of course."
          Saul had known Matsudo casually, from scientific conferences and by reputation, for many years. But the man was still somewhat of an enigma to him. For instance, why had he volunteered to come on this mission? Of all the types who would sign up to leave Earth, spend seventy-three years of a seventy-eight-year mission in slot sleep, and return to a world grown alien and strange, which category applied to Akio? Was he an idealist, following Captain Miguel Cruz's dream of what the mission might mean to mankind? Or was he an exile, like so many on this expedition?
          Perhaps, like me, he's a little of both.
          Matsudo ran a hand through his lustrous black hair, as thick as any youth's. "Just pick me out a head-cold virus, will you be so kind, Saul? Something that will challenge the crew enough to keep up their antibody production and T cell counts. They needn't even notice it, for all I care."
          Saul spoke a chain of letters aloud, and a new page appeared. "The customer's always right," he ruminated aloud. "And you're in luck! We seem to have eighty varieties of head cold on sale."
          "Surprise me," Matsudo said. But then he frowned and held up both hands. "No! On second thought, let me choose! I don't want any of your experimental monsters loose right now, no matter what you say about the wonders of symbiosis!"
          Saul pushed off to one side as Akio bent forward to peer at the list of available diseases, muttering softly to himself. Obviously, Matsudo had left his contact lenses out again.
          He's about three decimeters taller than his grandfather, Saul thought. And yet he's suspicious of change. A scientist, and yet he's too conservative to get a corneal implant that would let him see without aid.
          What ever happened to the innovative, future-hungry Japanese of so long ago?
          For that matter, what had happened to Israel, his own homeland? How could the descendants of the Negev pioneers, the most potent warriors in two centuries, slowly decline into superstition and cultism? What had turned clear-eyed Sabras into cowed sheep who let the Levite and Salawite fanatics just walk in and take over?
          The mysteries were part of a greater one that still amazed Saul, how courage seemed to be leaking away from humanity, even as the Hell Century was ending and better times appeared near at last.
          It wasn't a calming train of thought. Biological science was in just as bad shape. The bright hopes offered by Simon Percell and the genetic engineers of the early part of the century had nearly collapsed in a series of scandals more than a decade ago, leaving only a stolid pharmaceutical industry and a few mavericks such as Saul to carry on.
          Earth was rapidly becoming unpleasant for mavericks — one of the reasons he was on this mission. Exile through space and time certainly beat some of the alternatives he had seen coming.
          "We will use rhinovirus TR-3-APZX-471," Matsudo announced, apparently satisfied with his selection. "Do you concur, Saul?"
          Saul already felt a sneeze coming on. "A naïve little varietal, but I'm sure you'll be amused by its presumption."
          "I beg your pardon?"
          "Never mind," he grumped. "As official keeper of small animals, I'll have an incubated vial of the nasty buggers in your in-box by tomorrow morning." He touched a key and the glowing inventory disappeared.
          Matsudo lifted himself easily in the one-eighth G of the Edmund's laboratory wheel, and sat on the counter. He sighed, and Saul could tell that his friend was about to go philosophical on him. Over the long journey from Earth they had exchanged countless chess games and views of the world, and never budged each other on any issue at all.
          "It's not much like back when we were in medical school, is it, Saul? You in Haifa and me in Tokyo? We were brought up to hate pathogens — the infectious viruses and bacteria and prions — to want only to wipe them from the face of the Earth. Now, we culture and use them. They are our tools."
          Saul nodded. Today half a physician's job involved careful application of those very horrors, serving them up judiciously to create challenges.
          "Exercise the patient's immune system, and let him do the rest," Saul said, nodding. "It's a better way, Akio. I only wish you'd see that my cyanutes are part of the same progression."
          Matsudo rolled his eyes. He and Saul had been over this many times.
          "Again, I regret that I cannot agree. In one case we teach the body to be strong and reject that which is foreign. But you coax it to accept an interloper, forever!"
          "Perhaps half of the cells in a human body are guest life forms, Akio... gut bacteria, follicle cleaners. They help us; we help them."
          Matsudo waved his hand. "Yes, yes. Most of what you call you, is not! I have heard it before. I know you see us not as individuals, Saul, but as great, synergistic hives of cooperating species." There was a biting edge to Matsudo's voice that Saul did not remember having heard before. Exaggeration was not Matsudo's usual style.
          "Akio..."
          Matsudo hurried on, though. "And what if you 're right, Saul? All of those organisms that share our bodies with us grew into symbiosis over millions of years. That is entirely different from throwing gene-tailored monsters into such a delicate balance on purpose!"
          Matsudo flushed slightly. Saul considered trying to explain one more time — that the cyanutes were descended from creatures that had lived peacefully in man for aeons. But of course, he knew how Akio would answer. After all the changes that had been made, the 'nutes were a new species, as different from their natural cousins as men were from apes.
          "Saul, the Movement to Restore and Reflect teaches us that we must think carefully before we interfere with nature. The Hell Century has shown how dangerous it can be to meddle where we don't understand."
          Glancing up at the microscope screen, where his tiny test subject was still being run through its paces, Saul saw that the animal was still throbbing near the needle — harried but well.
          "I..." He shook his head and went silent. Saul had an idea what was bothering his friend.
          "There's still no sign of the Newburn yet, is there?"
          Matsudo shook his head, his gaze on the floor. "Captain Cruz and his officers are still looking. Perhaps when the comet has calmed down some more, when the coma and ion tail are less noisy... Fortunately, there were only forty people aboard that one. If it had been one of the other slot tugs, the Sekanina, or the Whipple, or the Delsemme —" He shrugged.
          Saul nodded. No wonder Matsudo was irritable. More than three hundred men and women had been shipped from Earth five years ahead of Edmund — along with most of the expedition's massive equipment — chilled down to near freezing aboard four slender robot freighters, riding sunlight behind gossamer sails a thousand kilometers across.
          Only the "founder" team took the fast, energetically expensive track aboard the old Edmund Halley. They exhausted almost the last of their propellant to match the comet's furious retrograde orbit. When they arrived the first task awaiting the torch ship's crew was to recover the huge cylinders containing the deep-sleeping majority of the mission crew.
          There were disadvantages to each style of travel — torch ship or slot tug. Much of the Edmund staff had to take long turns enduring the boredom and cramped living of more than a year in space. As well, they shared the recently evident dangers of setting up the base.
          On the other hand, they had some control over their fate. It was not their lot to coast for years in near-frozen sleep, relying on someone else to catch up, capture their slim barge, and finally awaken them.
          Would the men and women aboard Newburn drift forever? If Cruz and his team never found the tug, might they be picked up by someone else, in some faraway age? What might they awaken to after such a long trip down the river of time?
          "It is going to be a long eighty years, Saul." Matsudo shook his head pensively, looking at the picture wall, vivid with Halley's Comet in its full glory against a backdrop of stars. The plasma and dust tails glittered like flapping banners, like plankton in a phosphorescent sea. "It is a long time until we see home again."
          Saul smiled, hiding his own misgivings for his friend's sake. "We'll sleep through most of it, 'Kio. And when we do get home we'll be rich and famous."
          Matsudo snorted at the thought, but he acknowledged Saul's intent with a smile. Irony was the common trait that made them friends, in spite of all their differences.
          A bell chimed and Saul looked up as the probe's needle withdrew from the watery, saline bead. The subject cyanute floated gray and limp now. The last test had been to prove that the creatures could still easily be killed, if ever the need arose.
          A creator's prerogative? he wondered. Or are my shoulders stooped imperceptibly under one more tiny guilt?
          Scavengers were already nosing up to the microscopic corpse. Saul reached over and turned the microscope off.

VIRGINIA

The place smelled of rank, unwashed man.
          Virginia's nose wrinkled when she entered the workout gym for her mandatory exercise period.
          We're strange creatures. Mammals evolve odors that make males aggressive, and all of us nervous around one another, and then we pack a whole crowd of people together into a tin crate for a year or more, and ask them to make nice.
          Actually, Virginia did not mind the smell all that much. She did not even mind men.
          They just aren't the reason I accepted exile into the twenty-second century, riding a speck of stardust and ice out into the Big Night.
          Virginia had her own motives. For her, volunteering for Project Halley had little to do with herding comets for harvest.
          She stripped down to her shorts and mounted a bicycle ergometer, attaching the bio-monitor straps. Virginia pushed the pedals, accelerating until the readout showed she was fulfilling Dr. van Zoon's orders.
          The workout gym was located in the Edmund Halley's gravity wheel, where most of the crew snoozed through their sleep periods under weight. Virginia understood the need to let blood and bones feel the Old Pull now and then to keep them in shape. But these thrice-weekly sessions with straps, pulleys, and ergometers struck her as truly burnt logic.
          She had considered monkeying with the med center's data flow, inserting simulated feedback from all these exercise machines. She could do it, too. Virginia wasn't modest about her competence in Data Intelligence. Lefty d'Amaria might be head of the department, but she was the best.
          Oh, well, I guess I need this, she thought as she pushed down on the pedals. Sweat began popping out, glistening on her olive skin.
          Normally, she took pride in keeping a taut physique. Back home in Hawaii, she had surfed nearly every other day. But now it seemed she had to shake off a lassitude that still hung over her after a year's chilled sleep. Until three weeks ago she had been suspended, life functions barely ticking over at just above freezing. Perhaps it was a lingering laziness from the slot drugs that had made her so reluctant to come down to the gym.
          Well, as long as I'm here, let's do it right.
          She bore down hard and pretended she was pedaling across the Lanai-Maui bridge. The omnipresent rumble of the gravity wheel faded into an imagined background of roaring wind and water. Virginia pictured that the door in front of her might let her out, blinking, into yellow sunshine and the rich scent of pineapple.

          Her muscles felt warm and stretched after the workout. And it was good to spend some time after showering just brushing her long black hair. Stepping back into her drab pullover was reminder enough, though. Maui lay a hundred million miles from here.
          You made your choice, girl. There are things to accomplish out here... things more important to you even than remaining in the Land of the Golden People.
          She decided to take a brisk walk around the gravity wheel before returning to the freefall portion of the ship. Virginia strode long-legged in the direction opposite to the wheel's spin.
          It seemed nobody was about. Dr. Marguerite van Zoon wasn't chivying the spacers to visit the gym these days. Those poor folk were sweating quite enough right now, and were exempt from the Walloon physician's obsession with exercise.
          Virginia's journey around the rim hallway took her past one of the spoke ladders and beyond, to the part of the wheel dedicated to laboratories. The doors were all closed, so she couldn't tell if the Biological Sciences section was being used right now. She paused by the door, her hand hesitating, half-raised toward the buzzer.
          Oh come on, Ginnie. It's not as if Saul Lintz will bite you. Why all these little-girl heart palpitations?
          All she knew was that the man held a fascination for her, more than she had felt toward anyone in years. Was it his worldly experience? Or the expression in his eyes — perseverance and quiet strength?
          Since she had been unslotted, she had hoped he would say something, make some first move. It was frustrating to realize, at last, that he simply assumed she saw him as a father figure. That left Virginia wondering if she should attempt an overture herself.
          Her hesitation over the buzzer lasted until she felt ridiculous.
          It would seem so contrived to barge in on him now. What would I say?
          Later there'll be opportunity to arrange something more casual. After all, what we have plenty of is time.
          At least that would do for an excuse. Oh, if only she understood people half as well as she did machines! She swiveled and left without disturbing the buzzer.
          As she walked down the rim corridor, she noticed all the ways in which the Edmund Halley had aged over the past year. The corridors no longer shone. Buff, color-coordinated wall panels had warped and even buckled in places. The old girl had not started this mission exactly in the blush of youth, and no space vessel of her size had ever been required to accelerate so far, for so long. The strain showed.
          Virginia thought she was past surprise, but as she approached another of the spoke ladders, she stopped and stared.
          Oh, it can't be this bad!
          An air vent dripped onto the gently curved hallway. Patchy, dark green growth discolored the floor where Coriolis effects had pushed a small puddle against the wall.
          Virginia's generous lips pursed in disgust as she stepped gingerly past the moldy infestation and climbed a damp ladder toward the hub, making a mental note to report this to maintenance. It was hard to believe she was the first to discover it.
          The rungs pressed against her body as she surrendered angular momentum to the rotating wheel. The spoke passageway was dim and dank and all too smelly. Only half the phosphor panels in this tunnel were working, making the ascent seem a bit like a trip through a city sewer.
          It's a good thing the Halley habitats will be ready soon, she thought. This creaky barge needs a long overhaul.
          There would be little enough for the four hundred members of the expedition to do during three-quarters of a century... investigating the mysteries of a major cometary nucleus... testing the sublimation control panels and the big Nudge Flingers... another busy time in thirty years or so as Halley neared its farthest reach from the sun, when Virginia would help calculate parameters for the all important Grand Maneuver... then the long fall toward Jupiter and finally, home.
          For most of the intervening time, nearly everybody would be asleep, accumulating Earthside pay in nearly dreamless slot state. That was when the small, rotating watch shifts would slowly refurbish poor Edmund.
          Seven decades ought to be time enough. It had better be. Come Halley's next fiery plunge into the inner solar system, this old bucket has to be in good enough shape to take us home again.
          Climbing hand over hand, Virginia felt her weight seep away into the ladder as she approached the grumbling bearings, where the null gravity of space resumed. The four spoke tunnels came together in a small, rotating, octagonal room.
          Just before reaching the hub, however, she blinked in stunned surprise at a small lubricant leak, spraying fine, greasy vapor into the passage.
          I knew most of Edmund's spacers have been called away to work on Halley Core. Still, there's no excuse for this! We're going to need the wheel for a long time to come!
          "Disgusting," she muttered aloud. "Simply disgusting."
          That was when a voice spoke from beyond the faint, oily jet.
          "I agree, Virginia."

         She glanced up quickly. A slightly paunchy man in a gray shipsuit floated by one of the two exits, his broad, Slavic mouth pouting in a sour expression. A wool cap was pulled down over sparse brown hair flecked with gray. His arms were long and powerful-looking, all the more so since he had no legs.
          Spacer Second Class Otis Sergeov had never appeared particularly disabled by his handicap. In fact, it seemed to make him quicker in microgravity. She had heard that Sergeov was now assigned to helping Joao Quiverian and the other astronomers studying Comet Halley.
          He was the oldest Percell Virginia had ever met.
          Being one of the first had its drawbacks. Simon Percell's famous early work in genetic surgery had made it possible for Sergeov's parents to have children at all. But a mosaic flaw had left him with only small nubs below his shorts.
          "Oh, hello, Otis," she greeted him. "Something has to be done about this. Has anyone reported it yet?"
          The Russian spacer shrugged. "Is doing what the hell good, reporting thing like this? Nobody does nothing about it, for sure," he groused bitterly in mixed Russian and English. "The Stchakai cretins!"
          Virginia blinked at the apparent non sequitur. Of course Captain Cruz would order repairs at once, when someone told him...
          Then she noticed that Sergeov wasn't even looking at the lubricant leak. Virginia rode the slowly rotating hub until she was even with the man, then edged past the intermittent spray and pushed off hard.
          The octagonal room seemed to spin around her. She had to grab twice in order to grip a rubberized handhold, and still her body collided with the padded wall. I'll never get this right! she thought as she fought to orient herself.
          Sergeov pointed, "You think Ortho bureaucrats will do anything about this thing, do you?" he snapped. "This?"Virginia blinked. He was glaring at a graffito scrawled on the bulkhead nearest the grumbling axis bearings.

          "Arc of the Sun," he identified the symbol, bitingly. The Kakashkiia bastards have followed us, even out here."
          "I've seen it before," Virginia said softly. She felt a littie short of breath over this unexpected sight. "Even in Hawaii..."
          "So?" Sergeov interrupted snidely. "Even in Land of the Golden People? Even in your techno-humanistic paradise?"
          Virginia's brow knotted. Back in mission training she had taken a dislike to Sergeov, fellow Percell or no. He had spent nearly all his life in space — turning his physical drawbacks into assets in freefall — and yet every time she encountered him she felt uncomfortable, as if the man radiated long-suppressed bitterness.
          She promised herself she would use her own computer to worm her way into the personnel files. She would see to it that they never shared a shift out of the slots during the seven decades ahead.
          "Goodbye, Otis. I have work to do." But he stopped her, seizing her arm.
          "You know this is not first incident," he said. "Only most blatant. Some of Arcists," he sneered, "refuse to even talk to Percells aboard. They avoid us like we are xherobiy... unclean!"
          Virginia shrugged. "Everybody's been under a lot of stress lately. That'll change when the habitats are completed, and once people have room to move around again. When we've unfrozen some folks from the slot tugs and get to look at some fresh faces for a change..."
          Sergeov's grip was iron-strong from years of hauling space gear around. "Might help symptoms," he insisted. "But the disease goes on. You saw what Earth was like when we left. One after another of shlyoocha Hot Belt countries pass laws restricting our rights... rights of all genetically enhanced people!"
          Virginia only wanted the man to let go of her arm. She tried reason.
          "The nations of equatorial Africa and America have had a hellish century, Otis. I don't like the specious turn their ideology has taken in recent years either, but at least they're environmentalists, nowadays. If they've become a bit fanatical in that direction well, anyone will admit it's an improvement over the way their grandfathers behaved. The pendulum will swing back again."
          Virginia did not like the expression on Sergeov's face. He looked at her as if she were pitiably, even criminally naïve.
          "You think so? But no, my dear young Percell. Is only the beginning! They are already at war with us!"
          His unshaven face drew closer. "And who can blame them? When Homo sapiens awakens to what is happening, more and more repression will come against us — the Successor Race. Nothing less than future generations are at stake here!"
          "Oh, come on, Otis." Virginia laughed dryly, trying to lighten the tone. "It's not like we few Percells are the next step in evol —"
          "No, you listen, girl!" Sergeov's eyes narrowed. "This is the main reason for all such paranoia, such persecution! Is hard to blame Neanderthals for trying to protect their obsolete form, after all. Species protect selves."
          He grinned severely. "But that does not mean we must let bastards squash us, either. Is up to us to act first, or perish!"
          Even though they were clearly alone, Virginia quickly looked about. She did not want to be around if this seditious talk was overheard. With no wasted motion she used a judo grip-break to yank her arm away hard, sending the man spinning back. Sergeov bumped his head on the unpadded wall.
          "Ow!" he protested in hurt surprise. "Yayatamiy! Govenka! What you do that for?"
          "You Uber extremists don't have the answer," she breathed. "You only give Percells a bad name by talking like that. We aren't Nietzsche's supermen. We're misunderstood human beings. That's all!"
          Sergeov grimaced, rubbing his head. "Ask the regular human beings, the Orthos, if they think us brothers," he grumped.
          Pushing the walls with her hands, Virginia backed away like a fish from a shark, even though Sergeov showed no inclination to follow her. Once down the hall a few feet, she spun about and kicked off down the dimly lit corridor toward her sanctuary.

          Everything in Virginia's private work capsule was neat, crisp, efficient. The screens and opalescent holo displays that surrounded her web-couch all operated perfectly. Far from home and everything she had known — even hurtling out of the solar system at thirty kilometers per second — this was the center of her universe. She made certain everything was in good working order.
          Officially, her role was to provide special support to Computations Section. But she had actually inveigled her way aboard this mission in hopes of getting some of her own research done. In the kind of scientific environment that was developing on Earth, the sorts of things she was interested in were frowned on.
          Bio-organic computers... machines that might really think... These were areas that had been diagnosed as improbable, even dangerous, by increasingly conservative twenty-first-century science. Even in her native Hawaii, her superiors had grown more and more uncomfortable with the attention her work was drawing from the outside world.
          But I know bio-organics can eventually outperform silicon and gallium! And machines can do better than moron mechanical water drawing and wood hewing. Stochastic processors can be made to think.
          Over to the right, tucked under a desktop, was the squat box containing her own, special simulation unit; the Kelmar organo computer had used up nearly all of her small personal-effects allowance, but it was worth it.
          Panel lights rippled as the hatch hissed shut behind her and she slipped onto the web-couch. Virginia belted herself in and spoke softly.
          "Hello, JonVon."
          The main holo screen glittered.

HELLO, VIRGINIA.
WILL IT BE WORK OR PLAY TODAY?

          She smiled. No doubt in the eighty years ahead much progress would be made. It had to happen — even in a growing tide of scientific conservatism.
          But right now her charge was the best there was — unconventional, using technology all but banned back home, but supreme in her own estimation.
          She had named the unit after John Von Neumann, inventor of the theory of games. The program/mainframe could mimic a human's response patterns well enough to pass a third-stage Turing test... fooling an unsuspecting person in a five-minute casual vid-phone conversation into thinking the face and voice on the other end of the line were those of a real person, not a computer.
          JonVon could even tell a dirty joke, leering just enough and chuckling at the right time.
          Unprecedented, yes. But stunts like that weren't true "machine intelligence" — not the way Virginia felt should be possible.
          The molecular hardware in that five-liter box should be good enough to model the complex standing wave in a human brain. She was sure of it. They didn't agree back home, of course, and so it had never really been given a chance.
          For the next few weeks she would have little time to engage in her private experiments. She had to use all her equipment, including JonVon, to supplement the ship's mainframe. Nearly all her energy was devoted to preparing those mathematical models Captain Cruz's spacers kept demanding.
          Later, though, during her years on watch, there would be time. Time for work and undiluted thought.
          Back in the twentieth century, they knew how to have daring dreams, she thought. They did not believe in limits. It was one reason she liked old-time flat-screen movies... and enjoyed simulating old-time film stars and long-ago poets.
          Those people nearly wrecked the world with their greed, but they did believe in ambition. They wouldn't have rested until they had machines that could think.
          She glanced at the timepiece etched indelibly under her left thumbnail. "How about twenty minutes of diversion, Johnny?" Virginia lifted a cable from the console and bared a whitish bump at the back of her head. When the connection clicked home, the symbols on the screen were accompanied by a rich voice inside her head.

POETRY, VIRGINIA?

          She answered quickly with an impulsive thread of verse:

Ka Honua
          — Earth, my home,
E hoomanao no au ia oe
          — I shall remember you.

I wonder what he likes
          to do,
And if he can spare me
          the time of day?

          The line to her acoustic nerve hummed.

MIXED STYLES, VIRGINIA?
DOES THE SECOND PART APPLY TO LOVE?

          She blushed. "Oh hush, silly. Come on now. Let's take a look at your conversation subroutines."

continue reading HEART OF THE COMET