Learning the World

by Ken MacLeod

  “Give us it then.”

  Darvin paced back and forth a few times before replying. In truth he was not as sceptical of aliens as he had sounded. The possibility was an old and respectable one in the astronomy of Seloh and Gevork; even in religion, the green tinge of the Queen had been associated with life, and the spectroscopy confirmed that. There had even been a delightful legend that the Queen of Heaven’s Daughters had been given life by the Queen, and while astronomers discounted that, they allowed that the green tinge of the Daughter stars might indicate the presence of life on any planets around them, while admitting they had no idea how such hypothetical life-bearing planets could filter the light from their suns. There was one outlandish, but established, suggestion that some kind of green plant could grow in space itself, perhaps from the surfaces of comets, but the difficulties of this idea were as obvious as the absence of imaginable alternatives to it.

  “Suppose what we have here,” he said, “is a natural object, but one unknown to astronomy. A new kind of comet. We know that a comet’s tail consists of gas glowing in the Sun’s rays.”

  “Yes,” said Orro.

  “Now, the gas is given off as the comet warms up, on approaching the Sun. Now if, if there were a kind of comet or similar body that began to outgas much farther out from the sun, the flow of gases would — if aligned towards the Sun — slow down the comet and make it brighter than it would otherwise appear.”

  Orro closed his eyes and tilted his head back. His lips moved. “That might just work,” he said at last. “It would require some damned ticklish and unlikely coincidences: mass, orientation, specific impulse… am I right in thinking that cometary outgassings don’t normally have any effect on their orbit?”

  “You are,” said Darvin. “This would have to be, as you say, something quite different from outgassings as we understand them. The gases propelled outward by radioactive heating within, perhaps?”

  “Radioactivity is a remarkably faint source of power,” said Orro. “Certainly in any concentrations found in nature, though there have been some experiments and calculations… all very speculative stuff, of course.”

  Darvin had never heard of work along these lines. “In Gevork?”

  Orro opened his eyes and stared at him; it seemed, through him. “Speculation.” It wasn’t clear to just what Orro applied the epithet. He waved a hand. “Ignore that. We can only describe what we incontestably have evidence for. So let us describe it.”

  “How?”

  Orro jumped off the perch, strode forward, and clasped Darvin’s hand. “A joint note to the journals? Or failing that, the physics wire? Does not ‘A Distant, Decelerating Celestial Object: Some Observations,’ by Darvin and Orro, of Five Ravines, have a certain ring to it?”

  “It does,” said Darvin. He returned the handshake. “If only I didn’t suspect that we’ve both made some ghastly mistake, which some undergraduate will spot straight away, in which case it’s a title that’ll ring in our ears for the rest of our lives.”

  They finished checking the calculations that evening. By midnight they had written the paper. It was brief, detailed, mostly mathematical, and included no speculation whatever about the nature of the decelerating object.

  “You know,” Darvin said, glancing it over one last time, “I can’t help thinking this looks a bit trashy and sensational.”

  Orro didn’t laugh. “When I close my eyes, I see its title as a screaming headline in large black type.”

  “That’s fatigue,” said Darvin. He helped himself to some tea. “But yes, I do worry about the effect on public opinion. In engineering tales, the arrival of aliens is invariably followed by mass panic.”

  “That’s fanciful,” said Orro. “It has never been tested.”

  “Well, in the nature of things, no,” said Darvin. “However, there was one incident back in the Dawn Age, when the first observations of signs of life on the Queen were published. That led to, if I recall my history books, a stock market bubble, a subsequent collapse, and a brief frenzy of religious persecution.”

  “That was the Dawn Age,” said Orro. “We are now in the Day.”

  “So we like to believe. A day in which dirigibles almost too high to see patrol our skies above the Broad Channel. When the Broad Channel itself is patrolled by warships from both shores. A day in which war with Gevork is openly spoken of, and not just in engineering tales.”

  “And a day in which many such as you and I cooperate like civilised men.”

  “That’s true,” said Darvin. “Perhaps a new kind of comet — even if it was thought to be an alien spaceship — would result in wonder rather than fear.”

  “How long,” Orro mused, “before amateurs with telescopes notice it?”

  “Several eights of eight-days, even with the best private telescopes, I should imagine.”

  “So there is no risk, really, of our discovery’s being preempted. We could hold back for a little while—”

  “I said ‘private,’ ” said Darvin. “I’m not willing to see Seloh’s Reach being beaten by Gevork on this discovery. Or by any other country.”

  “Nor me,” said Orro. He gave Darvin a troubled look. “Surely you don’t think I—”

  “Oh, no, not at all,” said Darvin. “But some of your — their astronomers may already have noticed the anomaly.”

  “I doubt it,” said Orro. “Gevorkian astronomy is focused, you might say, on the stars. Even the planets, leave alone comets, are regarded as almost beneath the notice of serious scientists.”

  “The other realms—”

  “Astrologers!”

  “That’s the problem,” said Darvin. “The sky-watchers of the Court of the Southern Rule pay a great deal of attention to comets as portents — their priorities are rather the reverse of your Gevorkians’. And their telescopes — say what you like about the beliefs and motives of their builders — are of the highest craft. They were producing detailed sky maps before our Dawn Age — we have one in the university’s museum. I should take another look at it, to see if it shows any earlier comets in the Daughters region. It might suggest how the sky-watchers would interpret this one.”

  “Well,” said Orro, with a shrug, “I doubt that we need worry about their panicking the populace. Or preceding us into print, for that matter.”

  Darvin was not so sure about that. “Some of their younger sky-watchers are talented and educated men, and they do have their own version of a popular press,” he pointed out. “They invented it, after all.”

  Orro wiped a hand across his tired eyes. “There’s one more thing we can do,” he said. “That is, to project the path of the… object, check it against your latest plates, and work out exactly when it will become visible to amateur astronomers, and indeed to the naked eye.”

  “The naked eye!” Darvin had all along assumed that the comet that now bore his name would one day be visible to everyone, but the thought now brought him up short. Since confirming Orro’s calculations he’d begun to think of it almost as a secret.

  “Why not?” said Orro. “A year or so from now, I’d guess. Let’s check it.”

  ’Tomorrow,” said Darvin.

  In the morning a low fog from the sea overlay Five Ravines. Darvin had to rely more than usual on his proximity sense as he flew to the university. The world was a grey haze interrupted by red flashes. On one sideways turn he noticed how the fog curled away from his wing tip, and reflected on how something like fog — smoke? steam? — might be used in Orro’s wind-tube experiments.

  But there were to be no such experiments that day. When he’d stepped along the hall, shaking drops of moisture from his fur, Darvin found Orro hanging asleep from the ceiling outside his door. Darvin tapped his wing joint. The other man shuddered, unfolded his wings, and blinked up. Inside his wings, he’d been clutching a satchel.

  “Have you been here all night?” Darvin asked.

  “No,” said Orro. “Not long. But I needed the sleep.”

  He bent
upward, caught the wooden slats of the ceiling with his hands, let go with his feet, and dropped upright and caught the satchel before it reached the ground. Scratching himself, he followed Darvin into the office. It took them an hour or so to work through Orro’s calculations and find where to look for the comet on the more recent plates, those from the past couple of eight-days. Darvin set up the pair of plates, adjusted the blink comparator, and found the comet, brighter than before. Orro noted the degrees of displacement along the vertical and horizontal axes, scribbled in his notebook, and nodded. “On target,” he said.

  They repeated this for nine pairs of plates. The comet’s path was exactly as Orro’s calculation predicted.

  On the tenth pair, there was no jump. Instead, the comet seemed to flash on and off in the same position. On closer examination, Darvin found that it was present on the earlier plate, but not on the later. On the eleventh pair, and all subsequent pairs, it was altogether gone.

  5 — Fast Probes

  14 364:07:06 08:12

  It’s strange when something you have been unaware of all your life goes away. Something is missing, and you don’t know what it is. But of course, we know what it is. It’s the minute sideways tug of deceleration, that insensible inclination toward the forward wall that all our lives has troubled our inner ear. You couldn’t spot it with a plumb line and the unaided eye. But now it’s gone, and we notice it. We’re in orbit around the Destiny Star. It’s hard for me to believe that the journey is over, that we’ve arrived. It’s even harder, I think, for the adults. Four hundred years is a long time to live in one place, even if the place is changing all the time as cities get demolished and landscapes get torn up and thrown into the drive, and new cities and landscapes built, and these in turn… So those of us who’ve known only the final form of the world and who’ve lived less than a couple of decades in it should be patient with them.

  I told myself that earlier this morning as I washed glasses and cleared up bottles. There were snoring bodies all over the place. Some of the younger children had to be cleaned and fed. Aren’t adults supposed to be responsible? Isn’t that the point?

  I suppose once in four hundred years isn’t bad. Or once in fourteen, which is all I can vouch for.

  14 364:07:08 22:15

  Today the fast probes were launched to the inner system: one each to the ringed gas giant, the waterworld, the asteroid belt, the rocky terrestrial, and the mercurial. Funnily enough, it’s the one to the gas giant that’ll take longest — it’s on the far side of the Destiny Star, or the sun, as I suppose we should now call it (it doesn’t look like one: from out here it’s still a star, though the brightest). We won’t hear back from it for about ten years. The rest will vary, but they’re all in Hohmann transfer orbits (therefore slow) except for the probe to the terrestrial. That one has a fusion drive and a whole atmosphere package. No lander, though there was an argument over that. It’s going at a fast clip and should only take half a year (by which time the planet will have moved farther away — right now it’s on our side of the sun). Then we’ll know what the source of the signals is. If you call them up you can see they’re very raw, very messy; they don’t look like they’ve got a lot encoded in them. They don’t look like a couple of science packages from a fast interstellar probe reporting back to the Red Sun system.

  The latest speculation is that they’re natural: check out Grey Universal’s sim of a pair of permanent electrical storms in stable, long-lasting Coriolis hurricanes.

  There’s something really strange about that. I can see it in my mind’s eye more vividly than in the sim: a whirling tower of cloud, lit up by regular lightning-flashes, over the raging oceans of a terrestrial planet. Rain hissing into the white-topped black waves. Around that endless storm (and its counterpart in the other hemisphere) you might catch glimpses of blue sky through gaps in the clouds. And away from it, perhaps, the bald rock of continents, wet or dry, with here and there a yellow splash of lichen or a coppery or green slick of algae, if there’s life down there at all.

  I wonder what it would be like to walk on that world; to hear through my suit’s phones the crackle and roar of the lightning storm; modulated, regular, surging and waning; a sound you could mistake for a signal, and take for a voice.

  Genetic machinery was falling out of the sky. It came packaged in tough spheroids a millimetre in diameter, surrounded by aerobraking structures consisting of long wispy cellulose filaments arranged in a radial pattern. The packages landed at random, most of them nowhere near a suitable substrate, or in places where that substrate was already occupied. Horrocks Mathematical thought it a most curious method of distributing genetic machinery. It reminded him of market stochastics, and he speculated that its design had been thus inspired.

  As he clambered on all fours across the rubble in the foothills of the now dormant reaction-mass tip by the forward wall, Horrocks noticed the source of the genetic packages: plants with green photoreceptors and red insect-attractors. The wind carried the packages away from them in puffy clouds. The plants grew in quite improbable places, in cracks in stones and from crevices between blocks. The dispersal method might not be as wasteful as it looked.

  He reached the edge of the tip and hesitated. Ahead of him stretched the monorail line, and beneath its pylons a long flat strip of grass that merged on both sides with the rolling hills and woods. He had almost had to crawl out of the lift station, and spent hours making his way over the rubble alongside the line. Now he had reached its end, and if he were to go farther he would have to call for transport, or walk.

  He was sure he could walk: it was a guaranteed function in his genetic repertoire, though not one he had ever attempted to access. Like the free-fall adaptations of the groundhogs, it was included as a backup. Horrocks didn’t know how he’d acquired his conviction that to walk with his head two metres above a hard surface in a ten-newton acceleration field was to risk serious brain damage, but the conviction was there, and deep. On his hands and feet he made his way on to the grass. The substrate felt a little spongy and damp. No doubt it served some hydroponic function, which fortuitously made it fairly safe to fall on. He walked his hands backward, crooking his knees, until all his weight was borne on the soles of his feet. His calf muscles and Achilles tendons stretched as if he were about to thrust off. In a manner he was. He remained squatting for a few minutes, turning and rolling his head until he had the glimmerings of an intuitive fix on the attitude display and control mechanisms. It was a bit like flying a scooter.

  He raised his hands from the ground and stretched out his arms. Keeping his back straight and facing straight ahead, he straightened his knees and slowly stood up. The view was breathtaking: he could see kilometres farther than he had a moment earlier. This was easier than he had thought. He looked down. The grass rushed up to his face, but it was the palms of his hands that it struck. He rolled, rubbing his wrists. The pain passed. It was just like misjudging a jump and hitting a wall too hard.

  After a few more attempts he managed to stand, then to walk, and before he quite realised it he was a hundred metres along the strip and making progress, his head and arms swaying as he moved along. He had just grasped the kinetic feedback involved when he toppled again. When next he got up he walked without thinking about it, and this worked.

  Ever so often a train whizzed past, in one direction or the other, buffeting him in its slipstream. At one point he noticed the light darkening. He looked up and saw that a mass of vapour had obscured the sunline. A minute or two later water started falling from the sky, in fast, fat drops. It was like a shower, except that the water came from only one direction, the vertical, and it was cold. Horrocks tugged the hood out of his collar and over his drenched hair, and turned up his heating. So much for the natural human environment, he thought. The default conditions of a sunliner’s final interior surface had been established many millennia ago to emulate those of the Moon’s primary, but Horrocks was beginning to harbour a suspicion that some mista
ke had been made: either the emulation had drifted from the original, or they’d picked the wrong planet to emulate. Surely humanity could not have evolved in such an environment! It was amazing that anyone survived down here without a space suit.

  After an hour or so it became evident that he had greatly underestimated the effort required to traverse a given distance by walking. Muscle groups that he seldom used in the axis and in the forward cone ached. Ahead he saw a monorail station. A little elementary trigonometry fixed its distance at about a kilometre. He reached it half an hour later and climbed the steps on hands and feet. When the next sternward train stopped he staggered across the platform, lurched through the door, and slumped on to a vacant seat beside a window, facing in the direction of travel. He threw back his hood and shook the water off his hair.

  The doors hissed and thudded shut and the train accelerated. Horrocks spent the rest of the trip with his hands clamped to the back of his head, to prevent further injury to his neck. The speed at which the landscape flashed past the windows was another frightening surprise. After his first dozen or so flinches at the rushing approach of some blurred object, a tree or a tower, Horrocks concentrated on the middle distance or the far-off upward curve of the ground. Trees, here growing up rather than out, looked liable at any moment to be borne off on the breeze, like the drifting genetic packages. Habitats and storage units were constructed of heavy, durable substances — stone or wood walls, sheet-diamond windows — in permanent battle with the unpredictable atmospheric conditions and the relentless downward pull of the acceleration field.

  He turned away from the window and eyed the other passengers, people for whom such conditions were normal. There were fourteen in the car. Four adult women, three adult men, and the others adolescents or younger children. Two of the women and two of the men gazed into space, their lips moving. The other three adults were sitting around a table, talking and laughing. The adolescents, four of them, were doing the same but louder, and the small children were playing some complicated game that involved running from one end of the carriage to the other. Horrocks was relieved to see that they, at least, wore intelligent clothing that would protect them if they fell. The adolescents were so lightly clad that they evidently counted on luck or reflex. The adults were better covered, but in structured or loose outfits that showed no sign of intelligence or ready adaptability to emergencies, and open at the cuffs or hems at that. All of his fellow-passengers adjusted to changes in the train’s motion by subtle muscular reflex, and appeared quite untroubled by its speed.