The Project Gutenberg eBook ofCritical differenceThis ebook is for the use of anyone anywhere in the United States and most other parts of the world at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this ebook or online atwww.gutenberg.org. If you are not located in the United States, you will have to check the laws of the country where you are located before using this eBook.Title: Critical differenceAuthor: Murray LeinsterIllustrator: H. R. Van DongenRelease date: August 5, 2022 [eBook #68686]Most recently updated: October 18, 2024Language: EnglishOriginal publication: United States: Street & Smith Publications, Inc, 1956Credits: Greg Weeks, Mary Meehan and the Online Distributed Proofreading Team at http://www.pgdp.net*** START OF THE PROJECT GUTENBERG EBOOK CRITICAL DIFFERENCE ***
This ebook is for the use of anyone anywhere in the United States and most other parts of the world at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this ebook or online atwww.gutenberg.org. If you are not located in the United States, you will have to check the laws of the country where you are located before using this eBook.
Title: Critical differenceAuthor: Murray LeinsterIllustrator: H. R. Van DongenRelease date: August 5, 2022 [eBook #68686]Most recently updated: October 18, 2024Language: EnglishOriginal publication: United States: Street & Smith Publications, Inc, 1956Credits: Greg Weeks, Mary Meehan and the Online Distributed Proofreading Team at http://www.pgdp.net
Title: Critical difference
Author: Murray LeinsterIllustrator: H. R. Van Dongen
Author: Murray Leinster
Illustrator: H. R. Van Dongen
Release date: August 5, 2022 [eBook #68686]Most recently updated: October 18, 2024
Language: English
Original publication: United States: Street & Smith Publications, Inc, 1956
Credits: Greg Weeks, Mary Meehan and the Online Distributed Proofreading Team at http://www.pgdp.net
*** START OF THE PROJECT GUTENBERG EBOOK CRITICAL DIFFERENCE ***
CRITICAL DIFFERENCEBY MURRAY LEINSTER[Transcriber's Note: This etext was produced fromAstounding Science Fiction, July 1956.Extensive research did not uncover any evidence thatthe U.S. copyright on this publication was renewed.]
[Transcriber's Note: This etext was produced fromAstounding Science Fiction, July 1956.Extensive research did not uncover any evidence thatthe U.S. copyright on this publication was renewed.]
I
Massy waked that morning when the only partly-opened port of his sleeping-cabin closed of itself and the room-warmer began to whir. He found himself burrowed deep under his covering, and when he got his head out of it the already-bright room was bitterly cold and his breath made a fog about him.
He thought uneasily,It's colder than yesterday!But a Colonial Survey officer is not supposed to let himself seem disturbed, in public, and the only way to follow that rule is to follow it in private, too. So Massy composed his features, while gloom filled him. When one has just received senior service rating and is on one's very first independent survey of a new colonial installation, the unexpected can be appalling. The unexpected was definitely here, on Lani III.
He'd been a Survey Candidate on Khali II and Taret and Arepo I, all of which were tropical, and a Junior Officer on Menes III and Thotmes—one a semiarid planet and the other temperate-volcanic—and he'd done an assistant job on Saril's solitary world, which was nine-tenths water. But this first independent survey on his own was another matter. Everything was wholly unfamiliar. An ice planet with a minus point one habitability rating was upsetting in its peculiarities. He knew what the books said about glacial-world conditions, but that was all.
The denseness of the fog his breath made seemed to grow less as the room-warmer whirred and whirred. When by the thinness of the mist he guessed the temperature to be not much under freezing, he climbed out of his bunk and went to the port to look out. His cabin, of course, was in one of the drone-hulls that had brought the colony's equipment to Lani III. The other emptied hulls were precisely ranged in order outside. They were duly connected by tubular galleries, and very painstakingly leveled. They gave an impression of impassioned tidiness among the upheaved, ice-coated mountains all about.
He gazed down the long valley in which the colony lay. There were monstrous slanting peaks on either side. They partly framed the morning sun. Their sides were ice. The flanks of every mountain in view were ice. The sky was pale. The sun had four sun-dogs placed geometrically about it. It shone coldly upon this far-out world. Normal post-midnight temperatures in this valley ranged around ten below zero—and this was technically summer. But it was colder than ten below zero now. At noon there were normally tiny trickling rills of surface-thaw running down the sunlit sides of the mountains—but they froze again at night and the frost replaced itself after sunset. And this was a sheltered valley—warmer than most of the planet's surface. The sun had its sun-dogs every day, on rising. There were nights when the brighter planets had star-pups, too.
The phone-plate lighted and dimmed and lighted and dimmed. They did themselves well on Lani III—but the parent world was in this same solar system. That was rare. Massy stood before the plate and it cleared. Herndon's face peered unhappily out of it. He was even younger than Massy, and inclined to lean heavily on the supposedly vast experience of a Senior Officer of the Colonial Survey.
"Well?" said Massy—and suddenly felt very undignified in his sleeping-garments.
"We're picking up a beam from home," said Herndon anxiously, "but we can't make it out."
Because the third planet of the sun Lani was being colonized from the second, inhabited world, communication with the colony's base was possible. A tight beam could span a distance which was only light-minutes across at conjunction, and not much over a light-hour at opposition—as now. But the beam communication had been broken for the past few weeks, and shouldn't be possible again for some weeks more. The sun lay between. One couldn't expect normal sound-and-picture transmission until the parent planet had moved past the scrambler-fields of Lani. But something had come through. It would be reasonable for it to be pretty well hashed when it arrived.
"They aren't sending words or pictures," said Herndon uneasily. "The beam is wabbly and we don't know what to make of it. It's a signal, all right, and on the regular frequency. But there are all sorts of stray noises, and still in the midst of it there's some sort of signal we can't make out. It's like a whine, only it stutters. It's a broken-up sound of one pitch."
Massy rubbed his chin reflectively. He remembered a course in information theory just before he'd graduated from the Service Academy. Signals made by pulses, and pitch-changes and frequency-variations. Information was what couldn't be predicted without information. And he remembered with gratitude a seminar on the history of communication, just before he'd gone out on his first field job as a Survey Candidate.
"Hm-m-m," he said with a trace of self-consciousness. "Those noises—the stuttering ones. Would they be, on the whole, of no more than two different durations? Like—hm-m-m—Bzz bzz bzzzzzz bzz?"
He felt that he lost dignity by making such ribald sounds. But Herndon's face brightened.
"That's it!" he said relievedly. "That's it! Only they're high-pitched like—" His voice went falsetto. "Bzz bzz bzz bzzzzz bzz bzz!"
It occurred to Massy that they sounded like two idiots. He said with dignity:
"Record everything you get, and I'll try to decode it." He added: "Before there was voice communication there were signals by light and sounds in groups of long and short units. They came in groups, to stand for letters, and things were spelled out. Of course there were larger groups which were words. Very crude system, but it worked when there was great interference, as in the early days. If there's some emergency, your home world might try to get through the sun's scrambler-field that way."
"Undoubtedly!" said Herndon, with even greater relief. "No question, that's it!"
He regarded Massy with great respect as he clicked off. His image faded. The plate was clear.
He thinks I'm wonderful, thought Massy wryly.Because I'm Colonial Survey. But all I know is what's been taught me. It's bound to show up sooner or later. Damn!
He dressed. From time to time he looked out the port again. The intolerable cold of Lani III had intensified, lately. There was some idea that sunspots were somehow the cause. He couldn't make out sunspots with the naked eye, but the sun did look pale, with its accompanying sun-dogs. Massy was annoyed by them. They were the result of microscopic ice-crystals suspended in the air. There was no dust on this planet, but there was plenty of ice! It was in the air and on the ground and even under it. To be sure, the drills for the foundation of the great landing-grid had brought up cores of frozen humus along with frozen clay, so there must have been a time when this world had known clouds and seas and vegetation. But it was millions, maybe hundreds of millions of years ago. Right now, though, it was only warm enough to have an atmosphere and very slight and partial thawings in direct sunlight, in sheltered spots, at midday. It couldn't support life, because life is always dependent on other life, and there is a temperature below which a natural ecological system can't maintain itself. The past few weeks, the climate had been such that even human-supplied life looked dubious.
Massy slipped on his Colonial Survey uniform with its palm-tree insignia. Nothing could be much more inappropriate than palm-tree symbols on a planet with sixty feet of permafrost. Massy reflected wryly,The construction gang calls it a blast, instead of a tree, because we blow up when they try to dodge specifications. But specifications have to be met! You can't bet the lives of a colony or even a ship's crew on half-built facilities!
He marched down the corridor from his sleeping room, with the dignity he painstakingly tried to maintain for the sake of the Colonial Survey. It was a pretty lonely business, being dignified all the time. If Herndon didn't look so respectful, it would have been pleasant to be more friendly. But Herndon revered him. Even his sister Riki—
But Massy put her firmly out of his mind. He was on Lani III to check and approve the colony installations. There was the giant landing-grid for spaceships, which took power from the ionosphere to bring heavily loaded space-vessels gently to the ground, and in between times took power from the same source to supply the colony's needs. It also lifted visiting spacecraft the necessary five planetary diameters out when they took off again. There was power-storage in the remote event of disaster to that giant device. There was a food-reserve and the necessary resources for its indefinite stretching in case of need. That usually meant hydroponic installations. There was a reason for the colony, which would make it self-supporting—here a mine. All these things had had to be finished and operable and inspected by a duly qualified Colonial Survey officer before the colony could be licensed for unlimited use. It was all very normal and official, but Massy was the newest Senior Survey Officer on the list, and this was the first of his independent operations. He felt inadequate, sometimes.
He passed through the vestibule between this drone-hull and the next. He went directly to Herndon's office. Herndon, like himself, was newly endowed with authority. He was actually a mining-and-minerals man and a youthful prodigy in that field, but when the director of the colony was taken ill while a supply ship was aground, he went back to the home planet and command devolved on Herndon.I wonder, thought Massy,if he feels as shaky as I do?
When he entered the office, Herndon sat listening to a literal hash of noises coming out of a speaker on his desk. The cryptic signal had been relayed to him, and a recorder stored it as it came. There were cracklings and squeals and moaning sounds, and sputters and rumbles and growls. But behind the façade of confusion there was a tiny, interrupted, high-pitched noise. It was a monotone whining not to be confused with the random sounds accompanying it. Sometimes it faded almost to inaudibility, and sometimes it was sharp and clear. But it was a distinctive sound in itself, and it was made up of short whines and longer ones of two durations only.
"I've put Riki at making a transcription of what we've got," said Herndon with relief as he saw Massy. "She'll make short marks for the short sounds, and long ones for the long. I've told her to try to separate the groups. We've got a full half hour of it, already."
Massy made an inspired guess.
"I would expect it to be the same message repeated over and over," he said. He added. "And I think it would be decoded by guessing at the letters in two-letter and three-letter words, as clues to longer ones. That's quicker than statistical analysis of frequency."
Herndon instantly pressed buttons under his phone-plate. He relayed the information to Riki, his sister, as if it were gospel. Massy remembered guiltily that it wasn't gospel. It was simply a trick recalled from his boyhood, when he was passionately interested in secret languages. His interest had faded when he realized he had no secrets to record or transmit.
Herndon turned from the phone-plate.
"Riki says she's already learned to recognize some groups," he reported, "but thanks for the advice. Now what?"
Massy sat down. He'd have liked some coffee, but he was being treated with such respect that the role of demigod was almost forced on him.
"It seems to me," he observed, "that the increased cold out here might not be local. Sunspots—"
Herndon jittered visibly. He silently handed over a sheet of paper with observation-figures on top and a graph below them which related the observations to each other. They were the daily, at-first-routine, measurements of the solar constant from Lani III. The graph-line almost ran off the paper at the bottom.
"To look at this," he admitted, "you'd think the sun was going out. Of course it can't be," he added hastily. "Not possibly! But there is an extraordinary number of sunspots. Maybe they'll clear. But meanwhile the amount of heat reaching us is dropping. As far as I know there's no parallel to it. Night temperatures are thirty degrees lower than they should be. Not only here, either, but at all the robot weather stations that have been spotted around the planet. They average forty below zero minimum, instead of ten. And—there is that terrific lot of sunspots...."
He looked hopefully at Massy. Massy frowned. Sunspots are things about which nothing can be done. Yet the habitability of a borderline planet, anyhow, can very well depend on them. An infinitesimal change in sun heat can make a serious change in any planet's temperature. In the books, the ancient mother planet Earth was said to have entered glacial periods through a drop of only three degrees in the planet-wide temperature, and to have been tropic almost to its poles from a rise of only six. It had been guessed that glacial periods in the planet where humanity began had been caused by coincidences of sunspot maxima.
This planet was already glacial to its equator. There was a genuinely abnormal number of sunspots on Lani, its sun. Sunspots could account for worsening conditions here, perhaps.That message from the inner planet could be bad, thought Massy,if the solar constant drops and stays down a while.But aloud he said:
"There couldn't be a really significant permanent change. Not quickly, anyhow. Lani's a Sol-type star, and they aren't variables, though of course any dynamic system like a sun will have cyclic modifications of one sort or another. But they usually cancel out."
He sounded encouraging, even to himself. But there was a stirring behind him. Riki Herndon had come silently into her brother's office. She looked pale. She put papers down on her brother's desk.
"But," she said evenly, "while cycles sometimes cancel, sometimes they enhance each other. They heterodyne. That's what's happening."
Massy scrambled to his feet, flushing. Herndon said sharply:
"What? Where'd you get that stuff, Riki?"
She nodded at the sheaf of papers she'd just laid down.
"That's the news from home." She nodded again, to Massy. "You were right. It was the same message, repeated over and over. And I decoded it like children decode each other's secret messages. I did that to Ken once. He was twelve, and I decoded his diary, and I remember how angry he was that I'd found out he didn't have any secrets."
She tried to smile. But Herndon wasn't listening. He read swiftly. Massy saw that the under sheets were rows of dots and dashes, painstakingly transcribed and then decoded. There were letters under each group of marks.
Herndon was very white when he'd finished. He handed the sheet to Massy. Riki's handwriting was precise and clear. Massy read:
"FOR YOUR INFORMATION THE SOLAR CONSTANT IS DROPPING RAPIDLY DUE TO COINCIDENCE OF CYCLIC VARIATIONS IN SUNSPOT ACTIVITY WITH PREVIOUS UNOBSERVED LONG CYCLES APPARENTLY INCREASING THE EFFECT MAXIMUM IS NOT YET REACHED AND IT IS EXPECTED THAT THIS PLANET WILL BECOME UNINHABITABLE FOR A TIME ALREADY KILLING FROSTS HAVE DESTROYED CROPS IN SUMMER HEMISPHERE IT IS IMPROBABLE THAT MORE THAN A SMALL PART OF THE POPULATION CAN BE SHELTERED AND WARMED THROUGH DEVELOPING GLACIAL CONDITIONS WHICH WILL REACH TO EQUATOR IN TWO HUNDRED DAYS THE COLD CONDITIONS ARE COMPUTED TO LAST TWO THOUSAND DAYS BEFORE NORMAL SOLAR CONSTANT RECURS THIS INFORMATION IS SENT YOU TO ADVISE IMMEDIATE DEVELOPMENT OF HYDROPONIC FOOD SUPPLY AND OTHER PRECAUTIONS MESSAGE ENDS FOR YOUR INFORMATION THE SOLAR CONSTANT IS DROPPING RAPIDLY DUE TO COINCIDENCE OF CYCLIC—"
Massy looked up. Herndon's face was ghastly. Massy said in some grimness:
"Kent IV's the nearest world your planet could hope to get help from. A mail liner will make it in two months. Kent IV might be able to send three ships—to get here in two months more. That's no good!"
He felt sick. Human-inhabited planets are far apart. The average distance of stars of all types—there is on an average between four and five light-years of distance between suns. They are two months' spaceship journey apart. And not all stars are sol-type or have inhabited planets. Colonized worlds are like isolated islands in an unimaginably vast ocean, and the ships that ply between them at thirty light-speeds seem merely to creep. In ancient days on the mother planet Earth, men sailed for months between ports, in their clumsy sailing ships. There was no way to send messages faster than they could travel. Nowadays there was little improvement. News of the Lani disaster could not be transmitted. It had to be carried, as between stars, and carriage was slow and response to news of disaster was no faster.
The inner planet, Lani II, had twenty millions of inhabitants, as against the three hundred people in the colony on Lani III. The outer planet was already frozen, but there would be glaciation on the inner world in two hundred days. Glaciation and human life are mutually exclusive. Human beings can survive only so long as food and power hold out, and shelter against really bitter cold cannot be improvised for twenty million people! And, of course, there could be no outside help on any adequate scale. News of the need for it would travel too slowly. One other world might hear in two months, and send what aid it could in four. But the next would not hear for four months, and could not send help in less than eight. It would take five Earth-years to get a thousand ships to Lani II—and a thousand ships could not rescue more than one per cent of the population. But in five years there would not be nearly so many people left alive.
Herndon licked his lips. There were three hundred people in the already-frozen colony. They had food and power and shelter. They had been considered splendidly daring to risk the conditions here. But all their home world would presently be like this. And there was no possibility of equipping everybody there as the colonists were equipped.
"Our people," said Riki in a thin voice, "all of them.... Mother and father and—the others. Our cousins. All our friends. Home is going to be like ... like that!"
She jerked her head toward a port which let in the frigid colony-world's white daylight. Her face worked.
Massy was aware of an extreme unhappiness on her account. For himself, of course, the tragedy was less. He had no family. He had very few friends. But he could see something that had not occurred to them as yet.
"Of course," he said, "it's not only their trouble. If the solar constant is really dropping like that ... why things out here will be pretty bad too. A lot worse than they are now. We'll have to get to work to save ourselves!"
Riki did not look at him. Herndon bit his lips. It was plain that their own fate did not concern them immediately. But when one's home world is doomed, one's personal safety seems a very trivial matter.
There was silence save for the crackling, tumultuous noises that came out of the speaker on Herndon's desk. In the midst of that confused sound there was a wavering, whining, high-pitched note which swelled and faded and grew distinct again.
"We," said Massy without confidence, "are right now in the conditions they'll face a good long time from now."
Herndon said dully:
"But we couldn't live here without supplies from home. Or even without the equipment we brought. But they can't get supplies from anywhere, and they can't make such equipment for everybody! They'll die!" He swallowed, and there was a clicking noise in his throat. "They ... they know it, too. So they ... warn us to try to save ourselves because ... they can't help us any more."
There are many reasons why a man can feel shame that he belongs to a race which can do the things that some men do. But sometimes there are reasons to be proud, as well. The home world of this colony was doomed, but it sent a warning to the tiny group on the colony-world, to allow them to try to save themselves.
"I ... wish we were there to ... share what they have to face," said Riki. Her voice sounded as if her throat hurt. "I ... don't want to keep on living if ... everybody who ... ever cared about us is going to die!"
Massy felt lonely. He could understand that nobody would want to live as the only human alive. Nobody would want to live as a member of the only group of people left alive. And everybody thinks of his home planet as all the world there is.I don't think that way, thought Massy.But maybe it's the way I'd feel about living if Riki were to die.It would be natural to want to share any danger or any disaster she faced. Which he was.
"L-look!" he said, stammering a little "You don't see! It isn't a case of your living while they die! If your home world becomes like this, what will this be like? We're farther from the sun! We're colder to start with! Do you think we'll live through anything they can't take? Food supplies or no, equipment or no, do you think we've got a chance? Use your brains!"
Herndon and Riki stared at him. And then some of the strained look left Riki's face and body. Herndon blinked, and said slowly:
"Why ... that's so! We were thought to be taking a terrific risk when we came here. But it'll be as much worse here—Of course! We are in the same fix they're in!"
He straightened a little. Color actually came back into his face. Riki managed to smile. And then Herndon said almost naturally:
"That makes things look more sensible! We've got to fight for our lives, too! And we've very little chance of saving them! What do we do about it, Massy?"
II
The sun was halfway toward mid-sky, and still attended by its sun-dogs, though they were fainter than at the horizon. The sky was darker. The mountain peaks reached skyward, serene and utterly aloof from the affairs of men. This was a frozen world, where there should be no inhabitants. The city was a fleet of metal hulks, neatly arranged on the valley floor, emptied of the material they had brought for the building of the colony. At the upper end of the valley the landing-grid stood. It was a gigantic skeleton of steel, rising from legs of unequal length bedded in the hillsides, and reaching two thousand feet toward the stars. Human figures, muffled almost past recognition, moved about a catwalk three-quarters of the way up. There was a tiny glittering below where they moved. They were, of course, men using sonic ice-breakers to shatter the frost which formed on the framework at night. Falling shards of crystal made a liquidlike flashing. The landing-grid needed to be cleared every ten days or so. Left uncleared, it would acquire an increasingly thick coating of ice. In time it could collapse. But long before that time it would have ceased to operate, and without its operation there could be no space travel. Rockets for lifting spaceships were impossibly heavy, for practical use. But the landing-grids could lift them out to the unstressed space where Lawlor drives could work, and draw them to ground with cargoes they couldn't possibly have carried if they'd needed rockets.
Massy reached the base of the grid on foot. It was not far from the village of drone-hulls. He was dwarfed by the ground-level upright beams. He went through the cold-lock to the small control-house at the grid's base.
He nodded to the man on standby as he got painfully out of his muffling garments.
"Everything all right?" he asked.
The standby operator shrugged. Massy was Colonial Survey. It was his function to find fault, to expose inadequacies in the construction and operation of colony facilities.It's natural for me to be disliked by men whose work I inspect, thought Massy.If I approve it doesn't mean anything, and if I protest, it's bad.He had always been lonely, but it was a part of the job.
"I think," he said painstakingly, "that there ought to be a change in maximum no-drain voltage. I'd like to check it."
The operator shrugged again. He pressed buttons under a phone-plate.
"Shift to reserve power," he commanded, when a face appeared in the plate. "Gotta check no-drain juice."
"What for?" demanded the face in the plate.
"You-know-who's got ideas," said the grid operator scornfully. "Maybe we've been skimping something. Maybe there's some new specification we didn't know about. Maybe anything! But shift to reserve power."
The face in the screen grumbled. Massy swallowed. It was not a Survey officer's privilege to maintain discipline. But there was no particular virtue in discipline here and now. He watched the current-demand dial. It stood a little above normal day-drain, which was understandable. The outside temperature was down. There was more power needed to keep the dwellings warm, and there was always a lot of power needed in the mine the colony had been formed to exploit. The mine had to be warmed for the men who worked to develop it.
The demand-needle dropped abruptly, and hung steady, and dropped again and again as additional parts of the colony's power-uses were switched to reserve. The needle hit bottom. It stayed there.
Massy had to walk around the standby man to get at the voltmeter. It was built around standard, old-fashioned vacuum tubes—standard for generations, now. Massy patiently hooked it up and warmed the tubes and tested it. He pushed in the contact-plugs. He read the no-drain voltage. He licked his lips and made a note. He reversed the leads, so it would read backward. He took another reading. He drew in his breath very quietly.
"Now I want the power turned on in sections," he told the operator. "The mine first, maybe. It doesn't matter. But I want to get voltage-readings at different power take-offs."
The operator looked pained. He spoke with unnecessary elaboration to the face in the phone-plate, and grudgingly went through with the process by which Massy measured the successive drops in voltage with power drawn from the ionosphere. The current available from a layer of ionized gas is, in effect, the current-flow through a conductor with marked resistance. It is possible to infer a gas' ionization from the current it yields.
The cold-lock door opened. Riki Herndon came in, panting a little.
"There's another message from home," she said sharply. Her voice seemed strained. "They picked up our answering-beam and are giving the information you asked for."
"I'll be along," said Massy. "I just got some information here."
He got into his cold-garments again. He followed her out of the control-hut.
"The figures from home aren't good," said Riki evenly, when mountains visibly rose on every hand around them. "Ken says they're much worse than he thought. The rate of decline in the solar constant's worse than we figured or could believe."
"I see," said Massy, inadequately.
"It's absurd!" said Riki fiercely. "It's monstrous! There've been sunspots and sunspot cycles all along! I learned about them in school! I learned myself about a four-year and a seven-year cycle, and that there were others! They should have known! They should have calculated in advance! Now they talk about sixty-year cycles coming in with a hundred-and-thirty-year cycle to pile up with all the others—But what's the use of scientists if they don't do their work right and twenty million people die because of it?"
Massy did not consider himself a scientist, but he winced. Riki raged as they moved over the slippery ice. Her breath was an intermittent cloud about her shoulders. There was white frost on the front of her cold-garments.
He held out his hand quickly as she slipped, once.
"But they'll beat it!" said Riki in a sort of angry pride. "They're starting to build more landing-grids, back home. Hundreds of them! Not for ships to land by, but to draw power from the ionosphere! They figure that one ship-size grid can keep nearly three square miles of ground warm enough to live on! They'll roof over the streets of cities. Then they'll plant food-crops in the streets and gardens, and do what hydroponic growing they can. They are afraid they can't do it fast enough to save everybody, but they'll try!"
Massy clenched his hands inside their bulky mittens.
"Well?" demanded Riki. "Won't that do the trick?"
Massy said: "No."
"Why not?" she demanded.
"I just took readings on the grid, here. The voltage and the conductivity of the layer we draw power from, both depend on ionization. When the intensity of sunlight drops, the voltage drops and the conductivity drops, too. It's harder for less power to flow to the area the grid can tap—and the voltage-pressure is lower to drive it."
"Don't say any more!" cried Riki. "Not another word!"
Massy was silent. They went down the last small slope. They passed the opening of the mine—the great drift which bored straight into the mountain. They could look into it. They saw the twin rows of brilliant roof-lights going toward the heart of the stony monster.
They had almost reached the village when Riki said in a stifled voice:
"How bad is it?"
"Very," admitted Massy. "We have here the conditions the home planet will have in two hundred days. Originally we could draw less than a fifth the power they count on from a grid on Lani II."
Riki ground her teeth.
"Go on!" she said challengingly.
"Ionization here is down ten per cent," said Massy. "That means the voltage is down—somewhat more. A great deal more. And the resistance of the layer is greater. Very much greater. When they need power most, on the home planet, they won't draw more from a grid than we do now. It won't be enough."
They reached the village. There were steps to the cold-lock of Herndon's office-hull. They were ice-free, because like the village walkways they were warmed to keep frost from depositing on them. Massy made a mental note.
In the cold-lock, the warm air pouring in was almost stifling. Riki said defiantly:
"You might as well tell me now!"
"We could draw one-fifth as much power, here, as the same sized grid would yield on your home world," he said grimly. "We are drawing—call it sixty per cent of normal. A shade over one-tenth of what they must expect to draw when the real cold hits them. But their estimates are nine times too high." He said heavily, "One grid won't warm three square miles of city. About a third of one is closer. But—"
"That won't be the worst!" said Riki in a choked voice. "Is that right? How much good will a grid do?"
Massy did not answer.
The inner cold-lock door opened. Herndon sat at his desk, even paler than before, listening to the hash of noises that came out of the speaker. He tapped on the desktop, quite unconscious of the action. He looked almost desperately at Massy.
"Did she ... tell you?" he asked in a numb voice. "They hope to save maybe half the population. All the children anyhow—"
"They won't," said Riki bitterly.
"Better go transcribe the new stuff that's come in," said her brother dully. "We might as well know what it says."
Riki went out of the office. Massy laboriously shed his cold-garments. He said uncomfortably:
"The rest of the colony doesn't know what's up yet. The operator at the grid didn't, certainly. But they have to know."
"We'll post the messages on the bulletin board," said Herndon apathetically. "I wish I could keep it from them. It's not fun to live with. I ... might as well not tell them just yet."
"To the contrary," insisted Massy. "They've got to know right away! You're going to issue orders and they'll need to understand how urgent they are!"
Herndon looked absolutely hopeless.
"What's the good of doing anything?" When Massy frowned, he added as if exhausted: "Seriously, is there any use? You're all right. A Survey ship's due to take you away. It's not coming because they know there's something wrong, but because your job should be finished about now. But it can't do any good! It would be insane for it to land at home. It couldn't carry away more than a few dozen refugees, and there are twenty million people who're going to die. It might offer to take some of us. But ... I don't think many of us would go. I wouldn't. I don't think Riki would."
"I don't see—"
"What we've got right here," said Herndon, "is what they're going to have back home. And worse. But there's no chance for us to keep alive here! You are the one who pointed it out! I've been figuring, and the way the solar-constant curve is going—I plotted it from the figures they gave us—it couldn't possibly level out until the oxygen, anyhow, is frozen out of the atmosphere here. We aren't equipped to stand anything like that, and we can't get equipped. There couldn't be equipment to let us stand it indefinitely! Anyhow the maximum cold conditions will last two thousand days back home—six Earth-years. And there'll be storage of cold in frozen oceans and piled-up glaciers—It'll be twenty years before home will be back to normal in temperature, and the same here. Is there any point in trying to live—just barely to survive—for twenty years before there'll be a habitable planet to go back to?"
Massy said irritably:
"Don't be a fool! Doesn't it occur to you that this planet is a perfect experiment-station, two hundred days ahead of the home world, where ways to beat the whole business can be tried? If we can beat it here, they can beat it there!"
Herndon said detachedly:
"Can you name one thing to try here?"
"Yes," snapped Massy. "I want the walk-heaters and the step-heaters outside turned off. They use power to keep walkways clear of frost and doorsteps not slippery. I want to save that heat!"
Herndon said without interest:
"And when you've saved it, what will you do with it?"
"Put it underground to be used as needed!" Massy said angrily. "Store it in the mine! I want to put every heating-device we can contrive to work in the mine! To heat the rock! I want to draw every watt the grid will yield and warm up the inside of the mountain while we can draw power to do it with! I want the deepest part of the mine too hot to enter! We'll lose a lot of heat, of course. It's not like storing electric power! But we can store heat now, and the more we store the more will be left when we need it!"
Herndon thought heavily. Presently he stirred slightly.
"Do you know, that is an idea—" He looked up. "Back home there was a shale-oil deposit up near the icecaps. It wasn't economical to mine it. So they put heaters down in bore-holes and heated up the whole shale deposit! Drill-holes let out the hot oil vapors to be condensed. They got out every bit of oil without disturbing the shale! And then ... why ... the shale stayed warm for years. Farmers bulldozed soil over it and raised crops with glaciers all around them! That could be done again. They could be storing up heat back home!"
Then he drooped.
"But they can't spare power to warm up the ground under cities. They need all the power they've got to build roofs. And it takes time to build grids."
Massy snapped:
"Yes, if they're building regulation ones! By the time they were finished they'd be useless! The ionization here is dropping already. But they don't need to build grids that will be useless later! They can weave cables together on the ground and hang them in the air by helicopters! They wouldn't hold up a landing ship for an instant, but they'll draw power right away! They'll even power the helis that hold them up! Of course they've defects! They'll have to come down in high winds. They won't be dependable. But they can put heat in the ground to come out under roofs, to grow food by, to save lives by. What's the matter with them?"
Herndon stirred again. His eyes ceased to be dull and lifeless.
"I'll give the orders for turning off the sidewalks. And I'll send what you just said back home. They ... should like it."
He looked very respectfully at Massy.
"I guess you know what I'm thinking right now," he said awkwardly.
Massy flushed. It was not dignified for a Colonial Survey officer to show off. He felt that Herndon was unduly impressed. But Herndon didn't see that the device wouldn't solve anything. It would merely postpone the effects of a disaster. It could not possibly prevent them.
"It ought to be done," he said curtly. "There'll be other things to be done, too."
"When you tell them to me," said Herndon warmly, "they'll get done! I'll have Riki put this into that pulse-code you explained to us and she'll get it off right away!"
He stood up.
"I didn't explain the code to her!" insisted Massy. "She was already translating it when you gave her my suggestion!"
"All right," said Herndon. "I'll get this sent back at once!"
He hurried out of the office.This, thought Massy irritably,is how reputations are made, I suppose. I'm getting one.But his own reaction was extremely inappropriate. If the people of Lani II did suspend helicopter-supported grids of wire in the atmosphere, they could warm masses of underground rock and stone and earth. They could establish what were practically reservoirs of life-giving heat under their cities. They could contrive that the warmth from below would rise only as it was needed. But—
Two hundred days to conditions corresponding to the colony-planet. Then two thousand days of minimum-heat conditions. Then very, very slow return to normal temperature, long after the sun was back to its previous brilliance. They couldn't store enough heat for so long. It couldn't be done. It was ironic that in the freezing of ice and the making of glaciers the planet itself could store cold.
And there would be monstrous storms and blizzards on Lani II as it cooled. As cold conditions got worse the wire grids could be held aloft for shorter and shorter periods, and each time they would pull down less power than before. Their effectiveness would diminish even faster than the need for effectiveness increased.
Massy felt even deeper depression as he worked out the facts. His proposal was essentially futile. It would be encouraging, and to a very slight degree and for a certain short time it would palliate the situation on the inner planet. But in the long run its effect would be zero.
He was embarrassed, too, that Herndon was so admiring. Herndon would tell Riki that he was marvelous. She might—though cagily—be inclined to agree. But he wasn't marvelous. This trick of a flier-supported grid was not new. It had been used on Saril to supply power for giant peristaltic pumps emptying a polder that had been formed inside a ring of indifferently upraised islands.
All I know, thought Massy bitterly,is what somebody's showed me or I've read in books. And nobody's showed or written how to handle a thing like this!
He went to Herndon's desk. Herndon had made a new graph on the solar-constant observations forwarded from home. It was a strictly typical curve of the results of coinciding cyclic changes. It was the curve of a series of frequencies at the moment when they were all precisely in phase. From this much one could extrapolate and compute—
Massy took a pencil, frowning unhappily. His fingers clumsily formed equations and solved them. The result was just about as bad as it could be. The change in brightness of the sun Lani would not be enough to be observed on Kent IV—the nearest other inhabited world—when the light reached there four years from now. Lani would never be classed as a variable star, because the total change in light and heat would be relatively minute. But the formula for computing planetary temperatures is not simple. Among its factors are squares and cubes of the variables. Worse, the heat radiated from a sun's photosphere varies not as the square or cube, but as the fourth power of its absolute temperature. A very small change in the sun's effective temperature, producible by sunspots, could make an altogether disproportionate difference in the warmth its worlds received.
Massy's computations were not pure theory. The data came from Sol itself, where alone in the galaxy there had been daily solar-constant measurements for three hundred years. The rest of his deductions were based ultimately on Earth observations, too. Most scientific data had to refer back to Earth to get an adequate continuity. But there was no possible doubt about the sunspot data, because Sol and Lani were of the same type and nearly equal size.
Using the figures on the present situation, Massy reluctantly arrived at the fact that here, on this already-frozen world, the temperature would drop until CO2, froze out of the atmosphere. When that happened, the temperature would plummet until there was no really significant difference between it and that of empty space. It is carbon dioxide which is responsible for the greenhouse effect, by which a planet is in thermal equilibrium only at a temperature above its surroundings—as a greenhouse in sunlight is warmer than the outside air.
The greenhouse effect would vanish soon on the colony-world. When it vanished on the mother planet—
Massy found himself thinking,If Riki won't leave when the Survey ship comes, I'll resign from the Service. I'll have to if I'm to stay. And I won't go unless she does.
III
"If you want to come, it's all right," said Massy ungraciously.
He waited while Riki slipped into the bulky cold-garments that were needed out-of-doors in the daytime, and were doubly necessary at night. There were heavy boots with inches-thick insulating soles, made in one piece with the many-layered trousers. There was the air-puffed, insulated over-tunic with its hood and mittens which were a part of the sleeves.
"Nobody goes outside at night," she said when they stood together in the cold-lock.
"I do," he told her. "I want to find out something."
The outer door opened and he stepped out. He held his arm for her, because the steps and walkway were no longer heated. Now they were covered with a filmy layer of something which was not frost, but a faint, faint bloom of powder. It was the equivalent of dust, but it was microscopic snow-crystals frozen out of the air by the unbearable chill of night.
There was no moon, of course, yet the ice-clad mountains glowed faintly. The drone-hulls arranged in such an orderly fashion were dark against the frosted ground. There was silence: stillness: the feeling of ancient quietude. No wind stirred anywhere. Nothing moved. Nothing lived. The soundlessness was enough to crack the eardrums.