Ringworld r-1

by Larry Niven

  No point in searching for the fleet. Louis wouldn't know what to look for. He went to wake Nessus.

  * * *

  Anchored by his teeth to an exercise rung, Nessus peered over Louis's shoulder. "I need certain stars for reference. Center that green-white giant and throw it on the scope screen …"

  The pilot's cabin was crowded. Louis hunched over the instrument panel, protecting buttons ftm the puppeteer's careless hooves.

  "Spectroanalysis … yes. Now the blue-and-yellow double at two o'clock …

  "I have my bearings. Swing to 348, 72."

  "What exactly am I looking for, Nessus? A cluster of fusion flames? No, you'd be using thrusters."

  "You must use the scope. When you see it, you will know."

  On the scope screen was a sprinkling of anonymous stars. Louis ran the magnification up until … "Five dots in a regular pentagon. Right?"

  "That is our destination."

  "Good. Let me check the distance. — Tanj! That's wrong, Nessus. They're too far away."

  No comment.

  "Well, they couldn't be ships, even if the distance meter isn't working. The puppeteer fleet must be moving at just under lightspeed. We'd see the motion."

  Five dim stars, in a regular pentagon. They were a fifth of a light year distant and quite invisible to the naked eye. At present scope magnificatim they would have to be full sized planets. In the scope screen one was faintly less blue, faintly dimmer than the others.

  A Kemplerer rosette. How very odd.

  Take three or more equal masses. Set them at the points of an equilateral polygon and give them equal angular velocities about their center of mass.

  Then the figure has stable equilibrium. The orbits of the masses may be circular or elliptical. Another mass may occupy the center of mass of the figure, or the center of mass may be empty. It doesn't matter. The figure is stable, like a pair of Trojan points.

  The difficulty is that there are several easy ways in which a mass can be captured by a Trojan point. (Consider the Trojan asteroids in Jupiter's orbit.) But there is no easy way for five masses to fall accidentally into a Kemplerer rosette.

  "That's wild," Louis murmured. "Unique. Nobody's ever found a Kemplerer rosette …" He let it trail off.

  Here between the stars, what could be lighting those objects?

  "Oh, no you don't," said Louis Wu. "You'll never make me believe it. What kind of an idiot do you take me for?"

  "What is it that you will not believe?"

  "You know tanj well what I won't believe!"

  "As you please. That is our destination, Louis. If you will take us within range, a ship will be sent to match our velocity."

  The rendezvous ship was a #3 hull, a cylinder with rounded ends and a flattened belly, painted shocking pink, and windowless. There were no engine apertures. The engines must be reactionless: thrusters of the human type, or something more advanced.

  On Nessus's orders Louis had let the other ship do the maneuvering. The Long Shot, on fusion drives alone, would have required months to match velocities with the puppeteer "fleet". The puppeteer ship had done it in less than an hour, blinking into existence alongside the Long Shot with her access tube already reaching like a glass snake toward the Long Shot's airlock.

  Disembarking would be a problem. There wasn't room to release all the crew from stasis at once. More important, this would be Speaker's last chance to take control of the ship.

  "Do you think he will obey my tasp, Louis?"

  "No. I think he'll risk one more, shot at stealing the ship. Tell you what we'd better do …"

  They disconnected the instrument panel from the Long Shot's fusion motors. It was nothing that the kzin couldn't fix, given a little time and a touch of the mechanical intuition possessed by any toolmaker. But he would not have the time …

  Louis watched the puppeteer move through the tube. Nessus was carrying Speaker's pressure suit. His eyes were tightly closed; which was a pity, because the view was magnificent.

  "Free fall," said Teela when he opened her crash couch. "I don't feel so good. Better guide me, Louis. Wbat's happening? Are we there?"

  Louis told her a few details while he guided her to the airlock. She listened, but Louis guessed she was concentrating on the pit of her stomach. She looked acutely uncomfortable. "There'll be gravity on the other ship," he told her.

  Her eyes found the tiny rosette where Loius pointed. It was a naked-eye object now, a pentagon of five white stars. She turned with astounded questions in her eyes. The motion spun her semicircular canals; and Louis saw her expression change in the moment before she bolted into the airlock.

  Kemplerer rosettes were one thing. Free-falt sickness was something else again. Louis watched her recede against the unfamiliar stars.

  As the couch cover opened, Louis said, "Don't do anything startling. I'm armed."

  The kzin's orange face did not change expression. "Have we arrived?"

  "Yeah. I've disconnected the fusion drive. You'd never reconnect it in time. We're in the sights of a pair of big ruby lasers."

  "Suppose I were to escape in hyperdrive? No, my mistake. We must be within a singularity."

  "You're in for a shock. We're in five singularities."

  "Five? Really? But you lied about the lasers, Louis. Be ashamed."

  At any rate, the kzin left his couch peaceably enough. Loins followed with the variable-sword at the ready. In the airlock the kzin stopped, suddenly caught by the sight of an expanding pentagon of stars.

  He could hardly have had a better view.

  The Long Shot, edging close in hyperdrive, had stopped half a light-hour ahead of the puppeteer "fleet": something less than the average distance between Earth and Jupiter. But the "fleet" was moving at terrible speed, falling just behind its own light, so that the light which reached the Long Shot came from much further away. When the Long Shot stopped the rosette had been too small to see. It had been barely visible when Teela left the lock. Now it was impressively large, and growing at enormous speed.

  Five pale blue dots in a pentagon, spreading across the sky, growing, spreading …

  For a flashing instant there were five worlds around the Long Shot. Then they were gone, not fading but gone, their receding light reddened to invisibility. And Speaker-To-Animals held the variable-sword.

  "Finagle's eyes!" Louis exploded. "Don't you have any curiosity at all?"

  The kzin considered. "I have curiosity, but my pride is much stronger." He retracted the wire blade and handed the variable-sword back to Louis. "A threat is a challenge. Shall we go?"

  * * *

  The puppeteer ship was a robot. Beyond the airlock the lifesystem was all one big room. Four crash couches, as varied in design as their intended occupants, faced each other in a circle around a refreshment console.

  There were no windows.

  There was gravity, to Louis's relief. But it was not quite Earth's gravity; nor was the air quite Earth's air. The pressure was a touch too high. There were smells, not unpleasant but odd. Louis smelled ozone, hydrocarbons, puppeteer — dozens of puppeteers — and other smells he never expected to identify.

  There were no corners. The curved wall merged into floor and ceiling; the couches and the refreshment console all looked half melted. In the puppeteer world there would be nothing hard or sharp, nothing that could draw blood or raise a bruise.

  Nessus sprawled bonelessly in his couch. He looked ridiculously, ludicrously comfortable.

  "He won't talk," Teela laughed.

  "Of course not," said the puppeteer. "I would only have had to start over when you arrived. Doubtless you have been wondering about -"

  "Flying worlds," the kzin interrupted.

  "And Kemplerer rosettes," said Louis. A barely audible hum told him that the ship was moving. He and Speaker stowed their luggage and joined the others in the couches. Teela handed Louis a red, fruity drink in a squeezebulb.

  "How much time have we got?" he asked the puppeteer.


  "An hour until we land. Then you will be briefed on our final destination."

  "That should be long enough. Okay, speak to us. Why flying worlds? Somehow it doesn't seem safe to throw habitable worlds about with such gay abandon."

  "Oh, but it is, Louis!" The puppeteer was terribly earnest. "Much safer than this craft, for instance; and this craft is very safe compared to most human-designed craft. We have had much practice in the moving of worlds."

  "Practice! How did that happen?"

  "To explain this, I must speak of heat … and of population control. You will not be embarrassed or offended?"

  They signified negative. Louis had the grace not to laugh; Teela laughed.

  "What you must know is that population control is very difficult for us. There are only two ways for one of us to avoid becoming a parent. One is major surgery. The other is total abstinence from sexual congress."

  Teela was shocked. "But that's terrible!"

  "It is a handicap. Do not misunderstand me. Surgery is not a substitute for abstinence; it is to enforce abstinence. Today such surgery can be reversed; in the past it was impossible. Few of my species will willingly undergo such surgery."

  Louis whistled. "I should think so. So your population control depends on will power?"

  "Yes. Abstinence has unpleasant side effects, with us as with most species. The result has traditionally been overpopulation. Half a million years ago we were half a trillion in human numbering. In kzinti numbering -"

  "My mathematics is good," said the kzin. "But these problems do not seem to relate to the unusual nature of your fleet." He was not complaining, merely commenting. From the refreshment console Speaker had procured a double-handed flagon of kzinti design and half a gallon's capacity.

  "But it does relate, Speaker. Half a trillion civilized beings produce a good deal of heat as a byproduct of their civilization."

  "Were you civilized so long ago?"

  "Certainly. What barbarian culture would support so large a population? We had long since run out of farming land, and had been forced to terraform two worlds of our system for agriculture. For this it was necessary to move them closer to our sun. You understand?"

  "Your first experience in moving worlds. You used robot ships, of course."

  "Of course … After that, food was not a problem. Living space was not a problem. We built high even then, and we like each other's company."

  "Herd instinct, I'll bet. Is that why this ship smells like a herd of puppeteers?"

  "Yes, Louis. It is reassuring to us to smell the presence of our own kind. Our sole and only problem, at the time of which I speak, was heat."

  "Heat?"

  "Heat is produced as a waste product of civilization."

  "I fail to understand," said Speaker-To-Animals.

  Louis, who as a flatlander understood perfectly, forebore to comment. (Earth was far more crowded than Kzin.)

  "An example. You would wish a light source at night, would you not, Speaker? Without a light source you must sleep, whether or not you have better things to do."

  "This is elementary."

  "Assume that your light source is perfect, that is, it gives off radiation only in the spectra visible to kzinti. Nonetheless, all light which does not escape through the window will be absorbed by walls and furniture. It will become randomized heat.

  "Another example. Earth produces too little natural fresh water for its eighteen billions. Salt water must be distilled through fusion. This produces heat. But our world, so much more crowded, would die in a day without the distilling plants.

  "A third example. Transportation involving changes in velocity always produces heat. Spacecraft filled with grain from the agricultural worlds produce heat on reentry and distribute it through our atmosphere. They produce more heat on takeoff."

  "But cooling systems -"

  "Most kinds of cooling systems only pump heat around, and produce more heat for power."

  "U-u-urr. I begin to understand. The more puppeteers, the more heat is produced."

  "Do you understand, then, that the heat of our civilization was making our world uninhabitable?"

  Smog, thought Louis Wu. Internal combustion engines. Fission bombs and fusion rockets in the atmosphere. Industrial garbage in the lakes and oceans. It's often enough that we've half-killed ourselves in our own waste products. Without the Fertility Board, would the Earth be dying now in its own waste heat?

  "Incredible," said Speaker-To-Animals. "Why didn't you leave?"

  "Who would trust his life to the many deaths of space? Only such a one as me. Should we settle worlds with our insane?"

  "Send cargos of frozen fertilized ova. Run the ships with crews of the insane."

  "Discussions of sex make me uncomfortable. Our biology is not adapted to such methods, but doubtless we could evolve something analogous … but to what purpose? Our population would be the same, and our world would still have been dying of its own waste heat."

  Irrelevantly, Teela said, "I wish we could see out."

  The puppeteer was astounded. "Are you sure? Are you not subject to the fear of falling?"

  "On a puppeteer ship?"

  "Ye-es. In any case, our watching cannot increase the danger. Very well." Nessus spoke musically in his own tongue, and the ship vanished.

  They could see themselves and each other; they could see four crash couches resting on emptiness, and the refreshment console in the middle. All else was black space. But five worlds glowed in white splendor behind Teela's dark hair.

  They were of equal size: perhaps twice the angular diameter of the full Moon as seen from Earth. They formed a pentagram. Four of the worlds were circled by strings of tiny, glaring lights: orbital suns giving off artificial yellow-white sunlight. These four were alike in brightness and appearance: misty blue spheres, their continental outlines invisible at this distance. But the fifth …

  The fifth world had no orbital lights. It glowed by its own light, in patches the shapes of continents and the colors of sunlight. Between the patches was a black that matched the black of surrounding space; and this black, too, was filled with stars. The black of space seemed to encroach on continents of sunlight.

  "I've never seen anything so beautiful," said Teela, with tears in her voice. And Louis, who had seen many things, was inclined to agree.

  "Incredible," said Speaker-To-Animals. "I hardly dared believe it. You took your worlds with you."

  "Puppeteers don't trust spacecraft," Louis said absently. There was a touch of cold in the thought that he might have missed this; that the puppeteer might have chosen someone in his place. He might have died without seeing the puppeteer rosette …

  "But how?"

  "I had explained," said Nessus, "that our civilization was dying in its own waste heat. Total conversion of energy had rid us of all waste products of civilization, save that one. We had no choice but to move our world outward from its primary."

  "Was that not dangerous?"

  "Very. Then was much madness that year. For that reason it is famous in our history. But we had purchased a reactionless, inertialess drive from the Outsiders. You may guess their price. We are still paying in installments. We had moved two agricultural worlds; we had experimented with other, useless worlds of our system, using the Outsider drive.

  "In any case, we did it. We moved our world.

  "In later millenia our numbers reached a full trillion. The dearth of natural sunlight had made it necessary to light our streets during the day, producing more heat. Our sun was misbehaving.

  "In short, we found that a sun was a liability rather than an asset. We moved our world to a tenth of a light year's distance, keeping the primary only as an anchor. We needed the farming worlds and it would have been dangerous to let our world wander randomly through space. Otherwise we would not have needed a sun at all."

  "So," said Louis Wu. "That's why nobody ever found the puppeteer world."

  "That was part of the reason."
>
  "We searclied every yellow dwarf sun in known space, and a number outside it. Wait a minute, Nessus. Somebody would have found the farmin plancts. In a Kemplerer rosette."

  "Louis, they were searching the wrong suns."

  "What? You're obviously from a yellow dwarf."

  "We evolved under a yellow dwarf star somewhat like Procyon. You may know that in half a million years Procyon will expand into the red giant stage."

  "Finagles heavy handl Did your sun blow up into a red giant?"

  "Yes. Shortly after we finished moving our world, our sun began the proem of expandon. Your fathers were still using the upper thigh bone of an antelope to crack skulls. When you began to wonder where our world was, you were searching the wrong orbits, about the wrong Suns.

  "We had brought suitable worlds from nearby systems, increasing our agricultural worlds to four and setting them in a Kemplerer rosette. It was necessary to move them all when the sun began to expand, and to supply them with sources of ultraviolet to compensate for the reddened radiation. You will understand that when the time came to abandon galaxy, two hundred years ago, we were well prepared. We had had practice in moving worlds."

  The rosette of worlds had been expanding for some tme. Now the puppeteer world glowed beneath their feet, rising, rising to engulf them. Scattered stars in the black seas had expanded, to become scares of small islands. The continents burned like sunfire.

  Long ago, Louis Wu had stood at the void edge of Mount Lookitthat. The Long Fall River, on that world, ends in the tallest waterfall in known space. Louis's eyes had followed it down as far as they could penetrate the void mist. The featureless white of the void itself had grasped at his mind, and Louis Wim, half hypnotized, had sworn to live forever. How else could he see all there was to we?

  Now he reaffirmed that decision. And the puppeteer world rose about him.

  "I am daunted," said Speaker-To-Animals. His naked pink tail lashed in agitation, though his furry face and burry voice carried no emotion. "Your lack of courage had deserved our contempt, Nessus, but our contempt has blinded us. Truly you are dangerous. Had you feared us enough, you would have ended our race. Your power is terrible. We could not have stopped you."