‘You certainly have: I’m quite impressed. Can you divide just as quickly?’
‘Very nearly, when you’ve had enough experience.’
Martens picked up the abacus, and started flicking the beads back and forth. Then he sighed.
‘Ingenious – but it doesn’t really help us. Even if it’s ten times as fast as a man with pencil and paper – which it isn’t – the computer was a million times faster.’
‘I’ve thought of that,’ answered Pickett, a little impatiently.
(Martens had no guts – he gave up too easily. How did he think astronomers managed a hundred years ago, before there were any computers?)
‘This is what I propose – tell me if you can see any flaws in it …’
Carefully and earnestly he detailed his plan. As he did so, Martens slowly relaxed, and presently he gave the first laugh that Pickett had heard aboard Challenger for days.
‘I want to see the skipper’s face,’ said the astronomer, ‘when you tell him that we’re all going back to the nursery to start playing with beads.’
There was scepticism at first, but it vanished swiftly when Pickett gave a few demonstrations. To men who had grown up in a world of electronics, the fact that a simple structure of wire and beads could perform such apparent miracles was a revelation. It was also a challenge, and because their lives depended upon it, they responded eagerly.
As soon as the engineering staff had built enough smoothly operating copies of Pickett’s crude prototype, the classes began. It took only a few minutes to explain the basic principles; what required time was practice – hour after hour of it, until the fingers flew automatically across the wires and flicked the beads into the right positions without any need for conscious thought. There were some members of the crew who never acquired both accuracy and speed, even after a week of constant practice: but there were others who quickly outdistanced Pickett himself.
They dreamed counters and columns, and flicked beads in their sleep. As soon as they had passed beyond the elementary stage they were divided into teams, which then competed fiercely against each other, until they had reached still higher standards of proficiency. In the end, there were men aboard Challenger who could multiply four-figure numbers on the abacus in fifteen seconds, and keep it up hour after hour.
Such work was purely mechanical; it required skill, but no intelligence. The really difficult job was Martens’, and there was little that anyone could do to help him. He had to forget all the machine-based techniques he had taken for granted, and rearrange his calculations so that they could be carried out automatically by men who had no idea of the meaning of the figures they were manipulating. He would feed them the basic data, and then they would follow the programme he had laid down. After a few hours of patient routine work, the answer would emerge from the end of the mathematical production line – provided that no mistakes had been made. And the way to guard against that was to have two independent teams working, cross-checking results at regular intervals.
‘What we’ve done,’ said Pickett into his recorder, when at last he had time to think of the audience he had never expected to speak to again, ‘is to build a computer out of human beings instead of electronic circuits. It’s a few thousand times slower, can’t handle many digits, and gets tired easily – but it’s doing the job. Not the whole job of navigating to Earth – that’s far too complicated – but the simpler one of giving us an orbit that will bring us back into radio range. Once we’ve escaped from the electrical interference around us, we can radio our position and the big computers on Earth can tell us what to do next.
‘We’ve already broken away from the comet and are no longer heading out of the solar system. Our new orbit checks with the calculations, to the accuracy that can be expected. We’re still inside the comet’s tail, but the nucleus is a million miles away and we won’t see those ammonia icebergs again. They’re racing on toward the stars into the freezing night between the suns, while we are coming home …
‘Hello, Earth … hello, Earth! This is Challenger calling. Challenger calling. Signal back as soon as you receive us – we’d like you to check our arithmetic – before we work our fingers to the bone!’
Summertime on Icarus
First published in Vogue, June 1960, as ‘The Hottest Piece of Real Estate in the Solar System’
Collected in Tales of Ten Worlds
When I wrote this story, I certainly never dreamed that one day I would have an asteroid named after me: in 1996 the International Astronomical Union rescued 4923 from anonymity. As a result, I am now the proud absentee landlord of about 100 square kilometres of real estate out around Mars. It doesn’t come anywhere near the Earth, so I’m not worried about Deep Impact type lawsuits.
When Colin Sherrard opened his eyes after the crash, he could not imagine where he was. He seemed to be lying, trapped in some kind of vehicle, on the summit of a rounded hill, which sloped steeply away in all directions. Its surface was seared and blackened, as if a great fire had swept over it. Above him was a jet-black sky, crowded with stars; one of them hung like a tiny, brilliant sun low down on the horizon.
Could it be the sun? Was he so far from Earth? No – that was impossible. Some nagging memory told him that the sun was very close – hideously close – not so distant that it had shrunk to a star. And with that thought, full consciousness returned. Sherrard knew exactly where he was, and the knowledge was so terrible that he almost fainted again.
He was nearer to the sun than any man had ever been. His damaged space-pod was lying on no hill, but on the steeply curving surface of a world only two miles in diameter. That brilliant star sinking swiftly in the west was the light of Prometheus, the ship that had brought him here across so many millions of miles of space. She was hanging up there among the stars, wondering why his pod had not returned like a homing pigeon to its roost. In a few minutes she would have passed from sight, dropping below the horizon in her perpetual game of hide-and-seek with the sun.
That was a game that he had lost. He was still on the night side of the asteroid, in the cool safety of its shadow, but the short night would be ending soon. The four-hour day of Icarus was spinning him swiftly toward that dreadful dawn, when a sun thirty times larger than ever shone upon Earth would blast these rocks with fire. Sherrard knew all too well why everything around him was burned and blackened. Icarus was still a week from perihelion but the temperature at noon had already reached a thousand degrees Fahrenheit.
Though this was no time for humour, he suddenly remembered Captain McClellan’s description of Icarus: ‘The hottest piece of real estate in the solar system.’ The truth of that jest had been proved, only a few days before, by one of those simple and unscientific experiments that are so much more impressive than any number of graphs and instrument readings.
Just before daybreak, someone had propped a piece of wood on the summit of one of the tiny hills. Sherrard had been watching, from the safety of the night side, when the first rays of the rising sun had touched the hilltop. When his eyes had adjusted to the sudden detonation of light, he saw that the wood was already beginning to blacken and char. Had there been an atmosphere here, the stick would have burst into flames; such was dawn, upon Icarus …
Yet it had not been impossibly hot at the time of their first landing, when they were passing the orbit of Venus five weeks ago. Prometheus had overtaken the asteroid as it was beginning its plunge toward the sun, had matched speed with the little world and had touched down upon its surface as lightly as a snowflake. (A snowflake on Icarus – that was quite a thought …) then the scientists had fanned out across the fifteen square miles of jagged nickel-iron that covered most of the asteroid’s surface, setting up their instruments and check-points, collecting samples and making endless observations.
Everything had been carefully planned, years in advance, as part of the International Astrophysical Decade. Here was a unique opportunity for a reasearch ship to get within a mere seventeen million mi
les of the sun, protected from its fury by a two-mile-thick shield of rock and iron. In the shadow of Icarus, the ship could ride safely round the central fire which warmed all the planets, and upon which the existence of all life depended. As the Prometheus of legend had brought the gift of fire to mankind, so the ship that bore his name would return to Earth with other unimagined secrets from the heavens.
There had been plenty of time to set up the instruments and make the surveys before Prometheus had to take off and seek the permanent shade of night. Even then, it was still possible for men in the tiny self-propelled space-pods – miniature spaceships, only ten feet long – to work on the night side for an hour or so, as long as they were not overtaken by the advancing line of sunrise. That had seemed a simple-enough condition to meet, on a world where dawn marched forward at only a mile an hour; but Sherrard had failed to meet it, and the penalty was death.
He was still not quite sure what had happened. He had been replacing a seismograph transmitter at Station 145, unofficially known as Mount Everest because it was a full ninety feet above the surrounding territory. The job had been a perfectly straightforward one, even though he had to do it by remote control through the mechanical arms of his pod. Sherrard was an expert at manipulating these; he could tie knots with his metal fingers almost as quickly as with his flesh-and-bone ones. The task had taken little more than twenty minutes, and then the radioseismograph was on the air again, monitoring the tiny quakes and shudders that racked Icarus in ever-increasing numbers as the asteroid approached the sun. It was small satisfaction to know that he had now made a king-sized addition to the record.
After he had checked the signals, he had carefully replaced the sun screens around the instrument. It was hard to believe that two flimsy sheets of polished metal foil, no thicker than paper, could turn aside a flood of radiation that would melt lead or tin within seconds. But the first screen reflected more than ninety per cent of the sunlight falling upon its mirror surface and the second turned back most of the rest, so that only a harmless fraction of the heat passed through.
He had reported completion of the job, received an acknowledgement from the ship, and prepared to head for home. The brilliant floodlights hanging from Prometheus – without which the night side of the asteroid would have been in utter darkness – had been an unmistakable target in the sky. The ship was only two miles up, and in this feeble gravity he could have jumped that distance had he been wearing a planetary-type space suit with flexible legs. As it was, the low-powered micro-rockets of his pod would get him there in a leisurely five minutes.
He had aimed the pod with its gyros, set the rear jets at Strength Two, and pressed the firing button. There had been a violent explosion somewhere in the vicinity of his feet and he had soared away from Icarus – but not toward the ship. Something was horribly wrong; he was tossed to one side of the vehicle, unable to reach the controls. Only one of the jets was firing, and he was pinwheeling across the sky, spinning faster and faster under the off-balanced drive. He tried to find the cutoff, but the spin had completely disorientated him. When he was able to locate the controls, his first reaction made matters worse – he pushed the throttle over to full, like a nervous driver stepping on the accelerator instead of the brake. It took only a second to correct the mistake and kill the jet, but by then he was spinning so rapidly that the stars were wheeling round in circles.
Everything had happened so quickly that there was no time for fear, no time even to call the ship and report what was happening. He took his hands away from the controls; to touch them now would only make matters worse. It would take two or three minutes of cautious jockeying to unravel his spin, and from the flickering glimpses of the approaching rocks it was obvious that he did not have as many seconds. Sherrard remembered a piece of advice at the front of the Spaceman’s Manual ‘When you don’t know what to do, do nothing.’ He was still doing it when Icarus fell upon him, and the stars went out.
It had been a miracle that the pod was unbroken, and that he was not breathing space. (Thirty minutes from now he might be glad to do so, when the capsule’s heat insulation began to fail …) There had been some damage, of course. The rear-view mirrors, just outside the dome of transparent plastic that enclosed his head, were both snapped off, so that he could no longer see what lay behind him without twisting his neck. This was a trivial mishap; far more serious was the fact that his radio antennas had been torn away by the impact. He could not call the ship, and the ship could not call him. All that came over the radio was a faint crackling, probably produced inside the set itself. He was absolutely alone, cut off from the rest of the human race.
It was a desperate situation, but there was one faint ray of hope. He was not, after all, completely helpless. Even if he could not use the pod’s rockets – he guessed that the starboard motor had blown back and ruptured a fuel line, something the designers said was impossible – he was still able to move. He had his arms.
But which way should he crawl? He had lost all sense of location, for though he had taken off from Mount Everest, he might now be thousands of feet away from it. There were no recognisable landmarks in his tiny world; the rapidly sinking star of Prometheus was his best guide, and if he could keep the ship in view he would be safe. It would only be a matter of minutes before his absence was noted, if indeed it had not been discovered already. Yet without radio, it might take his colleagues a long time to find him; small though Icarus was, its fifteen square miles of fantastically rugged no man’s land could provide an effective hiding place for a ten-foot cylinder. It might take an hour to locate him – which meant that he would have to keep ahead of the murderous sunrise.
He slipped his fingers into the controls that worked his mechanical limbs. Outside the pod, in the hostile vacuum that surrounded him, his substitute arms came to life. They reached down, thrust against the iron surface of the asteroid, and levered the pod from the ground. Sherrard flexed them, and the capsule jerked forward, like some weird, two-legged insect … first the right arm, then the left, then the right …
It was less difficult than he had feared, and for the first time he felt his confidence return. Though his mechanical arms had been designed for light precision work, it needed very little pull to set the capsule moving in this weightless environment. The gravity of Icarus was ten thousand times weaker than Earth’s: Sherrard and his space-pod weighed less than an ounce here, and once he had set himself in motion he floated forward with an effortless, dreamlike ease.
Yet that very effortlessness had its dangers. He had travelled several hundred yards, and was rapidly overhauling the sinking star of the Prometheus, when overconfidence betrayed him. (Strange how quickly the mind could switch from one extreme to the other; a few minutes ago he had been steeling himself to face death – now he was wondering if he would be late for dinner.) Perhaps the novelty of the movement, so unlike anything he had ever attempted before, was responsible for the catastrophe; or perhaps he was still suffering from the after-effects of the crash.
Like all astronauts, Sherrard had learned to orientate himself in space, and had grown accustomed to living and working when the Earthly conceptions of up and down were meaningless. On a world such as Icarus, it was necessary to pretend that there was a real, honest-to-goodness planet ‘beneath’ your feet, and that when you moved you were travelling over a horizontal plain. If this innocent self-deception failed, you were heading for space vertigo.
The attack came without warning, as it usually did. Quite suddenly, Icarus no longer seemed to be beneath him, the stars no longer above. The universe tilted through a right angle; he was moving straight up a vertical cliff, like a mountaineer scaling a rock face, and though Sherrard’s reason told him that this was pure illusion, all his senses screamed that it was true. In a moment gravity must drag him off this sheer wall, and he would drop down mile upon endless mile until he smashed into oblivion.
Worse was to come; the false vertical was still swinging like a compass needle th
at had lost the pole. Now he was on the underside of an immense rocky roof, like a fly clinging to a ceiling; in another moment it would have become a wall again – but this time he would be moving straight down it, instead of up …
He had lost all control over the pod, and the clammy sweat that had begun to dew his brow warned him that he would soon lose control over his body. There was only one thing to do; he clenched his eyes tightly shut, squeezed as far back as possible into the tiny closed world of the capsule, and pretended with all his might that the universe outside did not exist. He did not even allow the slow, gentle crunch of his second crash to interfere with his self-hypnosis.
When he again dared to look outside, he found that the pod had come to rest against a large boulder. Its mechanical arms had broken the force of the impact, but at a cost that was more than he could afford to pay. Though the capsule was virtually weightless here, it still possessed its normal five hundred pounds of inertia, and it had been moving at perhaps four miles an hour. The momentum had been too much for the metal arms to absorb; one had snapped, and the other was hopelessly bent.
When he saw what had happened, Sherrard’s first reaction was not despair, but anger. He had been so certain of success when the pod had started its glide across the barren face of Icarus. And now this, all through a moment of physical weakness! But space made no allowance for human frailties or emotions, and a man who did not accept that fact had no right to be here.
Collected Stories Of Arthur C. Clarke Page 107