02-World of Ptavvs

by Larry Niven

  The crater looked like an open pit mine now, with a sloping ring wall and then an almost flat rim and then another, deeper ring wall and... Kzanol/Greenberg looked down, grinning and squinting against the glare, trying to guess which layer was which gas. They had been drilling through a very thick blanket of ice, hundreds or thousands of feet thick. Perhaps it was nitrogen? Then the next layer, appearing now, would be oxygen.

  The plain and the space above it exploded in flame.

  "She blows!" Lew crowed, like a felon reprieved. A towering, twisting pillar of yellow and blue flame roared straight up out of the telescope, out of the pale plain where there had been the small white star of the Golden Circle. For a moment the star shone brightly through the flames. Then it was swamped, and the whole scope was fire. Lew dropped the magnification by a ten-factor to watch the fire spread. Then he had to drop it again. And again.

  Pluto was on fire. For billions of years a thick blanket of relatively inert nitrogen ice had protected the highly reactive layers below. Meteors, as scarce out here as sperm whales in a goldfish bowl, inevitably buried themselves in the nitrogen layer. There had been no combustion on Pluto since Kzanol's spaceship smashed down from the stars. But now hydrogen vapor mixed with oxygen vapor, and they burned. Other elements burned too.

  The fire spread outward in a circle. A strong, hot wind blew out and up into vacuum, fanning great sheets of flame over the boiling ices until raw oxygen was exposed. Then the fire dug deeper. There were raw metals below the thin sheet of water ice; and it was thin, nonexistent in places, for it had all formed when, the spaceship struck, untold eons ago, when food yeast still ruled Earth. Sodium and calcium veins; even iron burns furiously in the presence of enough oxygen and enough heat. Or chlorine, or fluorine; both halogens were present, blowing off the top of Pluto's frozen atmosphere, some burning with hydrogen in the first sheets of flame. Raise the temperature enough and even oxygen and nitrogen will unite.

  Lew watched his screen in single-minded concentration. He thought of his future great-great-grandchildren and wondered how he could possibly make them see this as he saw it now. Old and leathery and hairless and sedentary, he would tell those children: "I saw a world burning when I was young..." He would never see anything as strange.

  Pluto was a black disc almost covering his scope screen, with a cold highlight near the sunward arm. In that disc the broad ring of fire had almost become a great circle, with one arc crawling over the edge of the world. When it contracted on the other side of the world there would be an explosion such as could only be imagined. But in the center the ring was darkening to black, its fuel nearly burned out.

  The coldest spot within the ring was the point where the fire had started.

  The Golden Circle had gone straight up, ringing and shivering from the blast, with sheets of fire roaring past the wing and hull. Kzanol/Greenberg had the wind knocked out of him. Kzanol was just now recovering consciousness. The ship was not yet harmed. It certainly hadn't been harmed by the heat of combustion. The ship's underbelly was built to withstand fusion heat for weeks.

  But the pilot was out of control. His reflexes had taken over at the instant the shock wave hit, and then his conscious mind... He found himself his own master for the first time in weeks, and he made his decision. He turned off the fuel feed. The drive couldn't possibly be started again. Kzanol raged and told him to die, and he did, but it was too late. The ship, deprived of power, bucked and swooped in the burning wind.

  Kzanol/Greenberg cursed fluent and ancient English.

  Below him a wall of fire tens of miles high retreated to-ward the horizon. The ship hadn't turned over; the gyros must still be working.

  The buffeting from below eased as the firelight died. The ship began to fall.

  Deliberately, reluctantly, Lew took his eyes off the screen and shook himself. Then he turned on the radio. "All ships," he said. "Drive to Pluto at max. We can watch the fireworks on the way. Tartov, program us a course to land us on the dawn side of whatever's left of Cott's Crescent. Hexter, you haven't done anything useful lately. Find Ceres with a maser so I can fill them in to date. Comments?"

  "This is Tartov. Low, for Pete's sake! The planet's on fire! How can we land?"

  "We've got four million miles to drive. The fire should be out when we get there. Oh, all right, get us into an orbit, but you're still gonna program our landing."

  "I think we ought to leave a ship in orbit. Just in case."

  "All right, Mabe. We'll gamble for who stays up. More comments?"

  Three men and a woman pushed buttons that squirted. volatilized uranium into fusion tubes and followed it with hydrogen. A growing storm of neutrons produced fission which produced heat which produced fusion. Four blue-white stars formed, very long and very thin. The bright ends swung toward Pluto. They began to move.

  "That's that," Masney said wearily. "And a good thing, too. Do you suppose there ever was a telepathy amplifier?"

  "I'm sure there is. And it's not over yet." Luke was flexing his fingers and looking worried. Pluto showed on the screen before him, with the edge of the fire a straight line creeping west to east. "Lloyd, why do you think didn't want the Belt to beat us to Pluto? Why did we come after them, anyway? That amplifier is a new weapon! If the Belt takes it apart and makes one that humans can use, we could see the worst and most permanent dictatorship in history. It might never end at all."

  Masney looked at the future Luke had painted and, judging by his expression, found it evil. Then he grinned.

  "They can't land. It's all right, Luke. They can't get down to the helmet with that fire going."

  "That fire isn't burning any more where the honeymooner came down."

  Masney looked. "Right. Is Pluto still explosive?"

  "I don't know. There might still be pockets of unburned material. But they can go down if they want, regardless. All they have to do is land on the day side, where there's no hydrogen, and land so fast they don't burn through the nitrogen layer. They'd sink into it, of course, from heat leakage through the hulls, so they'd eventually have to dig their way out. But that's nothing. What counts is the hydrogen. Miss that and you probably won't start a fire.

  "Now, they'll almost certainly go down for the amplifier as soon as the fire stops. We've got to destroy it before they get it. Or after."

  "Take a look," said Lloyd.

  Four bright points formed in a cluster on the screen. In seconds they had grown into lines a mile long, all pointing in the same direction.

  "We've got some time," said Masney. "They're millions of miles from Pluto."

  "Not far enough." Luke reached to close the intership circuit. "Calling Heinlein. Anderson, the Belt fleet just took off for Pluto from four million miles away. How long?"

  "They started from rest?"

  "Close enough."

  "Lessee ... mmmmmmmmmm ... five hours ten minutes, approx. No less, maybe more, depending on whether they're scared of the fire."

  "How long for us?"

  "Fifty-nine hours now."

  "Thanks, Anderson." Luke turned off the radio. Strange, how Smoky had sat there without saying a word. In fact, he hadn't said much of anything lately.

  With a chill, Luke realized that Smoky's thoughts must run very like his own. With the ET a dead issue, the question was: Who got the helmet? Belt or Earth? And Smoky wasn't about to trust Earth with it.

  Larry Greenberg opened his eyes and saw darkness. It was cold. "The lights don't work," said a voice in his mind.

  "Did we crash?"

  "We did indeed. I can't imagine why we're still alive. GET UP."

  Larry Greenberg got up and marched down the aisle between the passengers' seats. His muscles, bruised and aching, seemed to be acting by themselves. He went to the pilot seat, removed the pilot and sat down. His hands strapped him, then folded themselves into his lap. There he sat. Kzanol stood beside him, barely in the range of his peripheral vision.

  "Comfortable?"

  "Not q
uite," Larry confessed. "Could you leave one arm free for smoking?"

  "Certainly." Larry found his left arm would obey him. He still couldn't move his eyes, though he could blink. He pulled a cigarette and lit it, moving by touch.

  He thought, "It's a good thing I'm one of those people who can shave without a mirror."

  Kzanol asked, "What does that have to do with anything?"

  "It means I don't get uncoordinated without my eyes."

  Kzanol stood watching him, a blurred mass at the edge of sight. Larry knew what he wanted. He wouldn't do it; he wouldn't ask.

  What did Kzanol look like? he wondered.

  He looked like a thrint, of course. Larry could remember being Kzanol/Greenberg, and all he had seen was a smallish, handsome, somewhat undergroomed thrint. But when he'd walked past Kzanol on his way to the pilot room, his fleeting glimpse had found something terrifying, something one-eyed and scaly and iridescent green, with gray giant earthworms writhing at the corners of a mouth like a slash in a child's rubber ball, with sharply pointed metallic teeth, with oversized arms and huge three-fingered hands like mechanical grabs.

  The thrintun voice was chilly, by its own standards. "Are you wondering about my oath?"

  "Oaths. Yes, now that you mention it."

  "You can no longer claim to be a thrint in a human body. You are not the being I gave my oath to."

  "Oaths."

  "I still want you to help me manage Earth."

  Larry had no trouble understanding even the inflections in overspeak, and Kzanol, of course, could now read his mind.

  "But you'll manage me," said Larry.

  "Yes, of course."

  Larry raised his cigarette and tapped it with a forefinger. The ash fell slower than mist past his gaze and disappeared from sight. "There's something I should tell you," he said.

  "Condense it. My time is short; I have to find something."

  "I don't think you should own the Earth any more. I'll stop you if I can."

  Kzanol's eating tendrils were doing something strange. Larry couldn't see what it was. "You think like a slave. Not a ptavv, a slave. You have no conceivable reason to warn me."

  "That's my problem."

  "Quite. DON'T MOVE UNTIL I RETURN." The command carried overtones of disgust. A dark blur that was Kzanol moved and vanished.

  Alone in the pilot room, Larry listened to the clanking, squeaking, and mental cursing that meant Kzanol was searching for something. He heard when the thrint sharply ordered the pilot to return to life and show him AT ONCE where he'd hidden the contaminated portable radar... The command, a mere explosion of frustration, stopped suddenly. So did the sounds of search.

  Presently Larry heard the airlock chugging to itself.

  The clerk was a middleman. It was his job to set priorities on messages sent into and received from deep space. At three in the morning he answered the ring of the outside phone.

  "Hello, Arms Maser Transceiving Station," he said a little sleepily. It had been a dull night.

  It was no longer dull. The small brunette who looked out of his screen was startlingly beautiful, especially to the man who saw her unexpectedly in the dead hours.

  "Hello. I have a message for Lucas Garner. He's on the way to Neptune, I think."

  "Lucas Garner? What I mean, what's the message?"

  "Tell him that my husband is back to normal, and he should take it into consideration. It's very important."

  "And who is your husband?"

  "Larry Greenberg. That's G-r-e"

  "Yes, I know. But he's beyond Neptune by now. Wouldn't Garner already know anything you know about Greenberg?"

  "Not unless he's telepathic."

  It was a tricky decision for a clerk. Maser messages cost like uranium, less because of the power needed and the wear and tear on the delicate machines than because of the difficulty of finding the .target. But only Garner could decide whether an undependable "hunch" was important to him. The clerk risked his job and sent the message.

  The fire had slowed now. Most of the unburned hydrogen had been blown before the fire, until it was congested into a cloud mass opposite on Pluto from the resting place of the Golden Circle. Around that cloud bank raged a hurricane of awesome proportions. Frozen rain poured out of the heavens in huge lens-shaped drops, hissing into the nitrogen snow. The layers above nitrogen were gone, vaporized, gas diluting the hydrogen which still poured in. On the borderline hydrogen burned fitfully with halogens, and even with nitrogen to form ammonia, but around most of the great circle the fires had gone out. Relatively small, isolated conflagrations ate their way toward the new center. The "hot" water ice continued to fall. When it had boiled the nitrogen away it would begin on the oxygen. And then there would be a fire.

  At the center of the hurricane the ice stood like a tremendous Arizona butte. Even the halogens were still frozen across its flat top, thousands of square miles of fluorine ice with near-vacuum above. Coriolis effects held back the burning wind for a time.

  On the other side of the world, Kzanol stepped out of the Golden Circle.

  He turned once to look back. The honeymoon ship was flat on her belly. Her landing gear was retracted, and a wide, smooth crater was centered under the drive exhaust cone. Star-hot hydrogen had leaked from the fusion tube for some time after its fuel was cut off. The fuselage was twisted, though not broken. Her forward wings had been jarred open, and now hung broken from their sockets. One tip of the triangular major wing curled up where it had stabbed against rock-hard ice.

  She was doomed, she was useless. Kzanol walked on.

  The thrintun space suit was a marvelous assemblage of tools. No changes had been made in it for centuries before Kzanol's time, for the design had long been perfect, but for an unsuspected flaw in the emergency systems, and the naive thrintun had never reached that level of sophistication which produces planned obsolescence. The temperature inside the suit was perfect, even a little warmer than in the ship.

  But the suit could not compensate for the wearer's imagination. Kzanol felt the outer chill as his ship fell behind. Miles-thick blankets of nitrogen and oxygen snow had boiled away here, leaving bubbly permafrost which showed dark and deep green in the light of his helmet lamp. There was fog, too, not dense but very deep, a single bank that stretched halfway around the world. The fog narrowed his universe to a circular patch of bubbly ice.

  Moving in great, easy flying hops, he reached the first rise of the crescent in forty minutes. It was six miles from the ship. The crescent was now a slightly higher rise of permafrost, scarred and pitted from the fire that had crossed it. Kzanol's portable radar, borrowed from the Circle's lockers, showed his goal straight ahead at the limit of its range. About a mile ahead, and almost a thousand feet deep in permafrost.

  Kzanol began to climb the slope.

  "We're out of arrows," the man in Number Two ship said gloomily. He meant missiles. "How do we protect ourselves?"

  Lew said, "We'll be on our way home before Garner comes within sniffing distance of Pluto. The best he can do is shoot at us as we pass. His arrows aren't good enough to hit us when we're moving that fast, except by accident. He knows it. He won't even try, because it might start the Last War."

  "He may decide the stakes are high enough."

  "Dammit, Tartov, what choice have we got? Garner must not be allowed to leave here with that amplifier! If he does, we'll see a period of slavery such as nobody has even dreamt of up to now," Lew exhaled noisily through his nostrils. "We've got to go down and destroy the thing by hand. Land on the dawn side and mount an expedition. Hexter, can you dismount a ship's radar so it'll still work?"

  "Sure, Lew. But it'll take two men to carry it."

  Tartov said, "You miss my point. Of course we've got to wreck the damn amplifier. But how can we prove to Garner that we did wreck it? Why should he trust us?"

  Lew ran spatulate fingers through tangled cotton hair. "My apologies, Tartov. That's a damn good question. Comments?"

&
nbsp; Kzanol aimed the disintegrator thirty degrees downward and flipped the firing switch.

  The tunnel formed fast. Kzanol couldn't see how fast. for there was nothing but darkness inside after the first second. A minor hurricane blew out of the tunnel. He leaned against the wind as against a wall. In the narrow cone of the beam the "wind" was clear, but beyond the edge it was a dust storm. The wind was dust, too, icy dust torn to particles of two and three molecules each by the mutual repulsion of the nuclei.

  After ten minutes Kzanol decided the tunnel must be getting too wide. The opening was less than a foot across; he used the disintegrator to enlarge it. Even when he turned off the digging tool he couldn't see very far into it.

  After a moment he walked into the darkness.

  With his left hand Larry reached out and shook the pilot's shoulder. Nothing. It was like a wax figure. He would probably have felt the same way. But the man's cheek was cool. He was not paralyzed, but dead.

  Somewhere in the back of his mind was Judy. It was different from the way it had been in the past. Now, he believed it. Even when separated by over three billion miles, he and Judy were somehow aware of each other. But no more than that.

  He couldn't tell her anything. He couldn't warn her that the Bug Eyed Whoosis was hours or minutes from owning the Earth.

  The pilot couldn't help him. He had had an instant to make a choice, that professional hauler of millionaires, and he had made first a right choice and then a wrong one. He had decided to die, killing everyone aboard ship, and that was right. But he should have turned off the fusion shield, not the fuel feed! Now he was dead, and Kzanol was loose.

  It was his fault. Without Larry Greenberg, Kzanol would have been blasted to gas when he made turnover for Pluto. He'd never have known the suit was on Pluto! The knowledge was galling.

  Where was his mind shield? Two hours ago he had held an impenetrable telepathic wall, a shield that had stood up to Kzanol's most furious efforts. Now he couldn't remember how he'd done it. He was capable of it, he knew that, and if he could hold it.