Critical Difference
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, Itтs 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 cornposed his features, while gloom ifiled him. When one has just received senior service rating and is on oneтs very first independent survey of a new colonial installation, the unexpected can be appalling. The unexpected was definitely here, on Lani III.
Heтd been a Survey Candidate on Khali II and Taret and Arepo I, all of which were tropical, and a junior officer on Menes Ill and Thotmesўone a semiarid planet and the other temperate-volcanicўand heтd done an assistant job on Sarilтs 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 peculiarites. 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 ternperature 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 colonyтs equipment to Lani III. The other emptied hills 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 zeroўand 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 valleyўwarmer than most of the planetтs surface. Thee sun had its sundogs 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 IIIўbut the parent world was in this same solar system. That was rare. Massy stood before the plate and it cleared. Hemdonтs 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.
уWell?ф said Massyўand suddenly felt very undignified in his sleeping-garments.
уWeтre picking up a beam from home,ф said Hem~lon anxiously, уbut we canтt make it out.ф
Because the third planet of the sun Lani was being colonized from the second, inhabited world, communication with the colonyтs 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 oppositionўas now. But the beam communication had been broken br the past few weeks, and shouldnтt be possible again for someЁ weeks more. The sun lay between. One couldnтt 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.
уThey arenтt sending words or pictures,ф said Hemdon uneasily. уThe beam is wabbly and we donтt know what to make of it. Itтs a signal, all right, and on the regular frequency. But there are all sorts of stray noises, and still in the midst of it thereтs some sort of signal we canтt make out. Itтs like a whine, only it stutters. Itтs a broken-up sound of one pitch.ф
Massy rubbed his chin reflectively. He remembered a course in information theory just before heтd graduated. from the Service Academy. Signals made by pulses, and pitch-changes and frequency-variations. Information was what couldnтt be predicted without information. And he remembered with gratitude a seminar on the history of communication, just before heтd gone out on. his first field job as a Survey Candidate.
уHm-m-m,ф he said with a trace of selfўconsciousness. уThose noisesўthe stuttering ones. Would they be, on the whole, of no more than two different durations? Likeўbzzzzz bzz bzz hzzzzzzт bzz?ф
He felt that he lost dignity by making such ribald sounds. But Herndonтs face brightened.
уThatтs it!ф he said relievedly. уThatтs it! Only theyтre high-pitched likeўф His voice went falsetto..; уBzz bzz bzz bzzzzz bzz bzzф
It occurred to Massy that they sounded like two idiots. He said with dignity: уRecord everything you get, and Iтll try to decode it.ф He added: уBefore 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 1etters,~ and things were spelled out. Of course there were larger groups, which, were words. Very crude syscem, but it worked when there was great interference, as in the early days. If thereтs some emergency, your home world might try to get through the sunтs scrambler-field that way.ф
уUndoubtedly!ф said Herndon, with even greater relief. уNo questiНn, thatтs it!ф He regarded Massy with great respect as he clicked off. His image faded. The plate was clear.
He thinks Iтm wonderful, thought Massy wryly. Because iтm Colonial Survey. But all 1 know is whatтs been taught me. itтs 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 couldnтt 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 couldnтt support life, because life is always dependent on other life, and there is a temperature below which a neutral ecological system canтt 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 canтt bet the lives of a colony or even a shipтs 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 didnтt look so respectful, it would have been pleasant to be more friendly. But Hemdon revered him. Even his sister Rikiўbut 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 colonyтs 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-supportingўhere a mine. All these things had had to be finished and operable and inspected by a duly qualified Colonial Survey officerт 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 dronehull and the next. He went directly to Herndonтs 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, Hemdon 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 faНade 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.
уIтve put Riki at making a transcription of what weтve got,ф said Herndon with relief as he saw Massy. уSheтll make short marks for the short sounds, and- long ones for the long. Iтve told her to try to separate the groups. Weтve got a full half hour of it, already.ф
Massy made an inspired guess.
уI would expect it to be the same message repeated over and over,ф he said. He added, уAnd I think it would be decoded by guessing at the letters in two-letter and three-letter words, as clues to longer ones. Thatтs quicker than statistical analysis of frequency.ф
Herndon instantly pressed buttons under his phoneplate. He relayed the information to Riki, his sister, as if it were gospel. Massy remembered guiltily that it wasnтt 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. -
Hemdon turned from the phone-plate. -
уRiki says sheтs already learned to recognize some groups,ф he reported, уbut thanks for the advice. Now what?"
Massy sat down. Heтd have liked some coffee, but he was being treated with such respect that the role of demigod was almost forced on him.
уIt seems to me,ф he observed, уthat the increased cold out here might not be local. Sunspotsўф
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.
уTo look at this,ф he admitted, уyouтd think the sun was going out. Of course it can't be,ф he added hastily. уNot possibly! But there is an extraordinary number of sunspots. Maybe theyтll clear. But meanwhile the amount of heat reaching us is dropping. As far as I know thereтs 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 . . .у
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 sНrious change in any planetтs 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:
уThere couldnтt be a really significant permanent change. Not quickly, anyhow. Laniтs a Sol-type star, and they arenтt variables, though of course any dynamic system like a sun will have cyclic modifications of one sort or another. But they usually cancel out.ф
He sounded encouraging, even to himself. But there was a stirring behind him. Riki Herndon had come silently into her brotherтs office. She looked pale. She put papers down on her brotherтs desk.
уBut,ф she said evenly, уwhile cycles sometimes cancel, sometimes they enhance each other. They heterodyne. Thatтs whatтs happening.ф
Massy scrambled to his feet, flushing. Herndon said sharply:
уWhat? Whereтd you get that stuff, Riki?ф
She nodded at the sheaf of papers sheтd just laid down.
уThatтs the news from home.ф She nodded again, to Massy. уYou were right. It was the same message, repeated over and over. And I decoded it like children decode each otherтs secret messages. I did that to Ken once. He was twelve, and I decoded his diary, and I remember how angry he was that Iтd found out he didnтt have any secrets.ф
She tried to smile. But Herndon wasnтt 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 heтd- finished.т He handed the sheet to Massy. Rikiтs handwriting was precise and clear. Massy read:
уFOR YOUR INFORMATION THE SOLAR CONSTANT IS DROPPING RAPIDLY DUE TO COINCIDENCE OF CYCLIC VARIATIONS IN SUNSPOT ACTIVITY WITH PREVIOUS UNOBSERVED LяNG 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 FROST 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 CYCLICўф
Massy looked up. Herndonтs face was ghastly. Massy said in some grimness:
уKent Ivтs 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 shipsўto get here in two months more. Thatтs no good!ф
