The Heart of the Comet

by David Brin

  Saul did not know what to say. “I’ll be careful.”

  “Care, or care not.” Ould-Harrad shrugged. “Do or do not. In the end, it is all by God’s will. We are helpless to resist.”

  The otters seemed to sense something even before he moved. They leaped forth and flicked off down the long, dim hallway. Ould-Harrad turned stiffly and walked away.

  He actually does seem to be walking, like onthe moon or onEarth, Saul thought as he watched the man depart. I wonder what his technique is.

  He swiveled and glided back toward Blue Rock Cave, pondering the effects of personal gravity.

  CARL

  The blackness seemed like a solid weight a vast hand clasped about the gray, battered ice. Carl hadn’t been high above the surface for months, and the arid bleakness of it struck him fully, bringing back memories of his years when open silent vacuum meant freedom, deft movement, effortless grace.

  Stars gleamed, their tiny brimming beacons of rose and sea azure and molten yellow shining like steady promises of another life— a realm filled with vibrant hues, a place beyond this bleak plain that the slow elliptical glide of orbit had drained of color.

  Now the encroaching darkness meant that there was nothing between the frozen waste and the beckoning stars—no planets swarm with clouds and lightning, not even a vagrant asteroid within view.

  They rode far below the ecliptic plane now, ten times farther from the disk of planets than Earth itself was from the sun. The outer solar system was vast beyond imagining. Carl looked toward the south, virtually all the solar system at his back. The sun’s dim radiance—a thousandth of that which warmed Earth—could not summon forth the full colors that marked the ice. Everywhere pools of shadow swallowed detail; most of Halley was an inky kingdom.

  —Take it careful now,—Jeffers sent.

  “Right,” Carl answered automatically, his reverie broken. He jetted down to alight near his friend. Together they glide-walked southward. Normally he would seek the polar cable and use a jet, be at the south pole in a few minutes. But these were not normal times.

  They edged around the hummock of orange-splashed ice. Empty storage drums were moored with spiderweb-thin lines to the lump of frozen waste—garbage left from some process now decades old, forgotten. Jeffers slunk from one drum to another, careful not to expose himself to the southward side. Carl followed him. It took an effort to stay on the ice, gingerly digging his clamp-toes in for each long step. He fought down the urge to leap, to fly above the mottled snowscape.

  Blithe spirit, he thought. That’s what i was once. Zipping around, all spit and vinegar. Carl Osborn, space daredevil. But now…it just doesn’t have thee same zest.

  There were only a few paths that would not take them through the thick dust fields, kicking up plumes that would give their position away. Jeffers motioned to him and they sprinted across a patch of brown spill, running almost horizontally in long gliding steps, boots finding leverage on knobs and juts of ice. They reached the shelter of a chem module, a stained cylinder long sucked dry.

  “They must be able to see us by now. I.”

  —Shhhh! This close, they can pick up even local comm.—

  Carl bent down for shelter, feeling mildly ridiculous. He glanced around the curved edge of the cylinder and took in what he could. Yes, definitely—new structures near the lips of the Nudge shafts. They looked makeshift, thrown together from old cargo canisters and struts. He could see nearly to the south pole itself. Neptune hung barely above the horizon, a faint green pinpoint.

  Under high magnification, Neptune’s equatorial bands made brown concentric circles, resembling a target.

  Some Ubers still wanted to fire the Nudge to make Halley a Neptunian satellite. They could harvest gases from the upper atmosphere settle on the largest moon. Carl wondered idly what it would be like to live out his days with a slumbering green giant filling the sky. Not a lot like California, no. Maybe I should’ve gone into the insurance business. But he still hoped to see Earth’s blues, and reds, and autumn browns again…

  —We see you.—An alert, young voice. Carl glanced around the edge but could spot no one ahead.

  “It’s Carl Osborn. I’ve come to talk.”

  —Got nothing to talk about. Jeffers told you our policy.—The voice was tense but determined.

  “Who is that?” Carl whispered, touching helmets with Jeffers.

  —Name’s Rostok. Saul revived him about ten, eleven months ago. Now he’s Quiverian’s number-two guy down here.—

  “What’s he work on?”

  Jeffers made a sour face. —Mounting the electromagnetic assemblies.—

  “Oh, great:” A Nudge engineer. One of those had to go lunatic.

  —If you come any closer we will not be responsible for the outcome.—

  “Not responsible! What kind of crap is that?”

  —We declare ourselves independent of Halley Command. —The voice was tighter, clipped.

  —The hell you will!—Jeffers snapped before Carl could motion him to silence.

  —We already have. And no Percell is going to tell us what to do!—

  Carl breathed deeply. It did no good to blow up at asinine speeches; he had learned that the hard way, through these years. Jeffers was visibly grinding his teeth; Carl signaled him to stay quiet. “What… do you want?”

  —Not food,—Rostok answered smugly. —We already have enough hydro set up here to feed ourselves. Found a nice thick vein of edible Halleyforms, too. Delicious. Feed ’em heat and they grow like crazy.—

  So we can’t starve them out, Cart thought automatically.

  —We want—hell, we already have! —control ofthe targeting of the Nudge.—

  Jeffers jumped up. —You bastards! That’s our gear, our labor that built it. Rostok, you put in couple of months. The rest of us been buildn’ the EM guns for years! I’m double-dammed if I’ll let some—uh!—

  Jeffers grunted as Carl yanked him down. “I’ll do the talking.”

  —Can it, Jeffers. We got the flingers, so we call the tune.—

  “You have no right to determine the Nudge,” Carl said as calmly as he could.

  —We got the flingers, and we represent Earth.—

  “The hell you do. You represent nobody.”

  —We speak for Earth. We won’t let you Percells take this plague carrier back into near-Earth orbit.—

  Carl had hoped that, with the diseases checked, people would become more reasonable. Looks like it’s just given some of them the energy to be real sons of bitches again.

  He opened in a reasonable tone. “That has to be decided in the Council. Look, Rostok, I’m coming out. I want to talk face to face.”

  Carl stood and walked around the edge of the cylinder. Was there some movement around a jumble of crates on the horizon? He squinted, then thumbed up the telescopics. Yes—figures working at something, looking this way.

  He heard mumbles on a side channel, then the clear voice of Joao Quiverian. —We warned you, Osborn.—

  A sudden brilliance cut the dim sunlight. It was invisible in the vacuum but cast stark shadows where it lanced into a hummock nearby. Steam exploded, stones rattled on Carl’s helmet. A geyser burst nearby as a second laser bolt splashed the ice. Carl dived back behind the cylinder.

  —That enough for you?—

  Carl blinked, blinded by the glare.

  Jeffers sent, —They’re usin’ those big industrial lasers—the spot welders. Cut the big girders with ’em. Can’t aim ’em much but Jeezus do they burn.

  “Shit!”

  —Don’t show yourself around here again.—

  Another blazing burst streaked into nearby ice. Blue-white gas billowed into a swelling sphere.

  “Damn,” Carl said grimly. “We can’t even use mechs against that—we’d lose too many. We need every one we’ve got for the Nudge.”

  Jeffers grimaced and swore steadily. —Prob’ly smash up the flingers if we tried.—

  “What the hell
can we do?”

  —That’s what I thought you’d know,—Jeffers said.

  “Shit!”

  Meetings. Carl fidgeted with his pen, shifted restlessly in his web-chair. Youcan judge the importance of a problem by how many endless meetings it generates.

  He watched the wall weather as much as he could— luscious hills rising from Lake Como in northern Italy, with water-skiers cutting white Vs in waters of ancient blue— but he had to appear to be intent, giving every faction its due attention. They were grouped in loose knots around the meeting room in Central. The Arcist insurrection had reopened the issue of Nudge targeting.

  A Pandora’s box, Carl thought moodily. And all this had to happen just now, before I could speak privately to the important people, gather support for what I’ve got to announce. He bit at the end of his pen, a nervous gesture he had picked up sometime in the last year. With over two hundred revived crew, there are plenty of members for each faction. And I have to let them all have their say, exhaust the energy Quiverian’s stirred up. Worst possible timing… as usual.

  They had been going nearly two hours now and the groups had lined up exactly as he could have predicted.

  The most popular idea was the mission’s original flight plan: a Jupiter flyby on the return to the inner solar system, but before the comet approached too close to the sun. They could swoop deep into the giant planet’s gravity well like a race car in a steep turn, stealing vital momentum.

  Using the south-pole flingers, they could aim the Jovian flyby to turn Halley into a short-period comet. That would make rescue from Earthspace easier and harvesting of Halley Core possible. The Plateau Three people favored the original plan, as did the solid majority of nonaligned crew.

  The Ubers— the radical Percells led by Sergeov— wanted a different variant of the Jupiter flyby. Their final goal, though, was genuinely bizarre— to abandon the inner solar system entirely, and return to the spaces out here. Fire the Nudge at a low impulse, they said, and during the flyby pass over Jupiter, rather than ahead of it. That would loop them outward again to rendezvous with Neptune. Use the Nudge again to slow Halley and get captured. Become a moon. Spread out, colonize the rock and ice of Triton. A colony of supermen, perfecting themselves beneath a sky filled with a dm green ball of methane-streaked clouds.

  Two vastly different plans, but both calling for rendezvous with Jupiter in 2135. Astronomy allowed many different destinations from that one gargantuan world.

  The Plateau Three spacers and Sergeov’s Ubers wereunited in their need for a Jovian flyby, but they made uneasy allies. They differed about many other things, and gave each other guarded glances.

  Carl had checked the mission requirements himself, not trusting anybody’s calculations. It would take a delta-V, a change in Halley’s current velocity, of 284 meters per second in the Nudge— aimed at 72 degrees north declination from the ecliptic. Not so easy. Possible, though, using thrusters located at the south pole.

  Medieval societies squabbled over rarefied points of theology… and now we argue vector targeting. Equally pointless, maybe…

  The irony of the Uber-Plateau Three alliance was that now the Arcists had virtually destroyed both options.

  To bring off a good Jupiter flyby on the inward-falling leg, they had to use the south-pole flingers. And the Arcists wanted above all costs to keep Earth pristine and safe from Halley contamination. If the Jupiter encounter came off badly in the crucial hours of encounter, Halley could be flung deep into the inner solar system. The Arcists would never go for a maneuver that brought Halley near the home world. To avoid that possibility, they would refuse use of the south pole unless they were in control. Quiverian and his fanatics would rather die in deep space than let anyone else handle the maneuver.

  He read the signs, and knew that the situation was close to war. If something wasn’t done, soon, there would be killing. So Carl had sent a squirt Earthside as soon as he returned… and gotten confirmation. He had to offer a good option to the Council, now, before factionalism made compromise impossible.

  Even if I have to fudge the truth…

  He waited for a natural break in the talk. The wall weather now showed a sloop tacking in high seas, her stately turn unhindered by glistening steel-blue waves that hammered her without pity or effect. Her sails billowed triumphantly, shimmering white beneath a hard cold sky. She’ll make port, he thought. You can see it in the way she moves.

  He let the talk run on for while. When the silence of confusion and doubt came, s he knew it would, he rose and began to speak. He caught and held the eyes of each faction leader in turn—Otis Sergeov hanging legless in air, arms folded adamantly; Joao Quiverian here under a truce, as solid as ever, eyes smoldering; Jeffers, who represented the Martian Way group, lean and sardonic; and the others, who had no particular politics, but did want a chance to live.

  Carl spoke slowly, conveying by gesture and expression more than through words the hope he had, the plea for confidence, for solidarity before this new threat.

  “This mission was planned around a planetary carom past Jupiter. That’s why we put launchers at the south pole— which are now unusable.”

  That put Quiverian on the spot. The others glared at the sallow Brazilian. Of course, Carl wasn’t quoting the man precisely. He hurried on before Quiverian could interrupt.

  “But the south pole Nudge isn’t our only option.” He flicked a tab on his sleeve and a chart appeared on Central’s main screen. “It would take a relatively simple Nudge to reach Earth itself. A change in velocity of only sixty-three meters per second, aimed about forty degrees south and nearly ninety degrees away from the sun would bring us home.”

  The men and women stirred, varying emotions flickering across their faces. Home.

  “But to do it accurately demands that we despin Halley first. We’d arc in near Earth, good for a quick jumpoff and rescue… but only after perihelion passage. We’d have to weather that terrible storm. It’s anyone’s guess how many of us would survive high summer on a comet.”

  He had let the frowns and scowls build; now he defused them. Quiverian was red as a beet, opening his mouth. Carl cut him off.

  “Of course, Earth Control might get a bit miffed…”

  They looked at each other, blinked, and guffawed. Their laughter released some of the long-building tension. Of course Earth would never allow a plan that brought Halleyform spores that near the atmosphere. Even Quiverian relaxed slightly, when it was clear that Carl had not been serious.

  “There are other alternatives to Jupiter,” Carl continued. “We could try for Venus— jump off in aeroshells, decelerate in the upper atmosphere. But that’s after perihelion again, and we might not survive slamming into that atmosphere at eighty kilometers a sec or so.”

  He swept the room with a long, penetrating gaze. Cap’n Cruz would’ve done this right, he thought. Or maybe he would’ve stopped all this factionalism long ago. I’ll never be the leader he was.

  “On the other hand, there is an encounter that’ll get us to a planet before perihelion, and at lower velocity— one with Mars.”

  A stir of disbelief. “Mars?”

  “You mean target… ?”

  “I didn’t know it could even be…”

  He went on swiftly, not giving anyone a chance to break in.

  “Look. We can’t allow a single faction to control our destiny—”

  “And we will not allow use of the south pole unless we have control!” Quiverian shouted.

  Carl held his palms up, open. “Okay. That means we have to abandon the Jupiter flyby totally. The next best mission demands a pass into the inner solar system, but not coming near Earth. Instead, we can vector the Nudge to Mars. The encounter itself won’t divert Halley much— but it’ll give us a chance to jump off.”

  Some engineers shook their heads. Carl kept on going, before the objections could begin.

  “We’ll build aerobrakes and swoop into the Martian atmosphere. It’s thin bu
t deep, a good target for us, especially since an encounter with any planetary atmosphere will be awful damn fast.”

  A spacer asked, “We could lose enough velocity on one pass?”

  Sharp question. “No. We’d have to do several maneuvers.” He ticked off fingers. “Aerobrake at Mars, divert outward to Jupiter. Aerobrake again there with a gravity assist. Pass inward to Venus, swing around, head for Mars again. By then we’ll have shed enough velocity to make a successful rendezvous brake in the Martian atmosphere. We can get out of the aero shells, come alongside Phobos.”

  A long silence. They stared at him.

  “But…” Keoki Anuenue muttered. “How long will all that take?”

  “Twenty years.”

  Gasps.

  Carl rode over the babble with, “That’s twenty added to the nearly eighty we’ll have been gone. But it will be worth it to get to Phobos Base, to safety and maybe eventually, home again. I should add that this plan has the approval of Earth Command.”

  A Plateau Three woman said angrily, “What’ll happen to Halley?”

  Carl shrugged. “JonVon shows it wheeling off into the outer system, back to its original home in the Oort Cloud, gone for good.”

  Jeffers said thoughtfully, “We could target Halley smack on Mars— give it an atmosphere!”

  “Sure,” Sergeov said, “and try aerobraking at same time. Impossible!”

  Jeffers began, “But—” He shut up as he noticed Carl’s signal to be quiet.

  “It’s a chance to live,” Carl said emphatically. “If we try the aerobrake and guide Halley to optimize that. Anything else is suicide.”

  “What can we expect at Mars?” Quiverian demanded suspiciously.

  “Quarantine. Maybe Earth’ll order us isolated on Diemos. Let the medicos study us until Earth is sure these diseases are controllable.”

  Another long silence. They all contemplated this new idea, letting it sink in.

  “Is possible?” Sergeov asked, scowling.

  Carl shrugged. “We might never be allowed into Earthspace— not that that’ll bother the Ubers, eh? Remember, though, that there are decent places to live in the small scientific colonies of the asteroids. Maybe we can even do some worthwhile pioneering on Mars itself.”