Heavy Planet

by Hal Clement

  “Power checking.” The voice from the speaking tube was a little deeper than Dondragmer’s. “Life support, acknowledge!”

  “Life support checking.”

  “Communication, acknowledge!”

  “Checking.”

  “Kervenser to the bridge for standby! I’m going outside. Research, give me outside conditions!”

  “One moment. Captain.” The pause was brief before the voice resumed, “Temperature 77; pressure 26.1; wind from 21, steady at 200 cables per hour; oxygen fraction standard at 0.0122.”

  “Thanks. That doesn’t seem too bad.”

  “No. With your permission, I’ll come out with you to get surface samples. May we set up the drill? We can get cores to a fair depth in less than ten hours.”

  “That will be all right. I may be outside before you get to the lock, if you take time to collect the drill gear, but you are cleared outside when ready. Tell Kervenser the number of your party, for the log.”

  “Thank you, Captain. We’ll be there right away.” Dondragmer relaxed at his station; he would not, of course, leave the bridge until his relief appeared, even with the engines stopped. Kervenser would be some minutes in arriving, since he would have to turn his current duties over to a relief of his own. The wait was not bothersome, however, since there was plenty to think about. Dondragmer was not the worrying type (the Mesklinite nervous system does not react to uncertainty in that way) but he did like to think situations out before he lived them. The fact that he was some ten or twelve thousand miles from help if the Kwembly were ever crippled was merely background, not a special problem. It did not differ essentially from the situation he had faced for most of his life on Mesklin’s vast seas. The principal ripple on his normally placid self-confidence was stirred up by the machine he commanded. It resembled in no way the flexible assemblage of rafts which was his idea of a ship. He had been assured that it would float if occasion arose; it actually had floated during tests on distant Mesklin where it had been built. Since then, however, it had been disassembled, loaded into shuttle craft and lifted into orbit around its world of origin, transferred in space to an interstellar flier, shifted back to another and very different shuttle after the three-parsec jump, and brought to Dhrawn?s surface before being reassembled. Dondragmer had personally supervised the disassembly and reconstruction of the Kwembly and her sister machines, but the intervening steps had not been carried out under his own eye. This formed the principal reason for his wanting to go outside now; high as was his opinion of Beetchermarlf and the rest of his picked crew, he liked firsthand knowledge. He did not, of course, mention this to Kervenser when the latter reached the bridge. It was something which went without saying. Anyway, the first officer presumably felt the same himself. “Maintenance checks are under way. The researchers are going out to sink a well, and I’m going out to look things over,” was all Dondragmer said as he resigned his station. “You can signal me with outside lights if necessary. It’s all yours.” Kervenser snapped two of his nippers light-heartedly. “I’ll ride it, Don. Enjoy yourself.” The captain left by way of the still open hatch which had admitted his relief, telling himself as he went that Kervenser wasn’t as casual as he sounded. Four decks down and sixty feet aft of the bridge was the main air lock. Dondragmer paused several times on the way to talk to members of his crew as they worked among the cords, beams, and piping of the Kwembly’s interior. By the time he reached the lock four scientists were already there with their drilling gear, and had started to don their air suits. The captain watched critically as they wriggled their long bodies and numerous legs into the transparent envelopes, made the tests for tightness, and checked their hydrogen and argon supplies. Satisfied, he gestured them into the lock and began suiting up himself. By the time he was outside the others were well on with setting up their apparatus. He glanced at them only briefly as he paused at the top of the ramp leading from lock to ground. He knew what they were doing and could take it for granted, but he could never be that casual about the weather. Even as he latched the outer lock portal behind him, he was looking at as much of the sky as the towering hull of his command permitted. The darkness was deepening very, very slowly as Dhrawn’s two-month rotation carried the feeble sun farther below the horizon. As at home, the horizon itself seemed to be somewhat above his level of sight all around. The gravity-squeezed atmosphere responsible for this effect would also set the stars twinkling violently when they became visible. Dondragmer glanced toward the bow, but the twin stars which guarded the south celestial pole, Fomalhaut and Sol, were still invisible. A few cirrus clouds showed above, drifting rapidly toward the west. Evidently the winds a thousand or two feet above were opposed to the surface ones, as was usual during the daytime. This might change shortly, Dondragmer knew; only a few thousand miles to the west was country in which the setting of the sun would make a greater temperature change than it did here, and there might be weather changes in the next dozen hours. Exactly what sort of changes, was more than his Mesklinite sailor background, even fortified with alien meteorology and physics, enabled him to guess. For the moment, though, all seemed well. He made his way down the ramp to the snow and a hundred yards to the east, partly to make sure of the rest of the sky and partly to get an overall view of his command before commencing a detailed inspection. The western sky was no more threatening than the rest, and he favored it with only a brief glance. The Kwembly looked just as usual. To a human being it would probably have suggested a cigar made of dough and allowed to settle on a flat table for a time. It was slightly over a hundred feet in length, between twenty and twenty-five in breadth, and its highest point was nearly twenty feet above the snow. Actually there were two such points; the upper curve of the hull, about a third of the way back, and the bridge itself. The latter was a twenty-foot crosspiece whose nearly square outlines somewhat spoiled the smooth curves of the main body. It was almost at the bow, permitting helmsman, commander, and conning personnel to watch the ground as they traveled almost to the point where the forward trucks covered it. The flat bottom of the vehicle was nearly a yard off the snow, supported on an almost continuous set of tread-bearing trucks. These were individually castered and connected by a bewildering rigging of fine cables, allowing the Kwembly to turn in a fairly short radius with reasonably complete control of her traction. The trucks were separated from the hull proper by what amounted to a pneumatic mattress, which distributed traction and adapted to minor ground irregularities. A caterpillarlike figure was making its way slowly along the near side of the land-cruiser, presumably Beetchermarlf continuing his inspection of the rigging. Twenty yards closer to the captain the short tower of the core drill had been erected. Above, clinging to the holdfasts which studded the hull but could hardly be seen at the captain’s distance, other crew members were climbing about as they inspected the seams for tightness. This, to a Mesklinite, was a nerve-stretching job. Acrophobia was a normal and healthy state of mind to a being reared on a world where polar gravity was more than six hundred times that of Earth, and even “home” gravity a third of that. Dhrawn’s comparatively feeble pull, scarcely thirteen hundred feet per second squared, took some of the curse off climbing, but hull inspection was still the least popular of duties. Dondragmer crawled back across the hard-packed mixture of white crystals and brown dust, interrupted by occasional sprawling bushes, and made his way up the side to help out with the job. The great, curved plates were of boron fiber bonded with oxygen-and fluorine-loaded polymers. They had been fabricated on a world none of the Mesklinites had ever seen, though most of the crew had had dealings with its natives. The human chemical engineers had designed those hull members to withstand every corrosive agent they could foresee. They fully realized that Dhrawn was one of the few places in the universe likely to be even worse in this respect than their own oxygen-and-water world. They were quite aware of its gravity. They had all these factors in mind when they synthesized the hull members and the adhesives which held them together: both the tempo
rary cements used during the testing on Mesklin and the supposedly permanent ones employed in reassembling the vehicles on Dhrawn. Dondragmer had every confidence in the skill of those men, but he could not forget that they had not faced and never expected to face the conditions their products were fighting. These particular parachute packers would never be asked to jump, though that analogy would have been lost on a Mesklinite. Much as the captain respected theory, he very well knew the gap between it and practice, so he devoted full attention to examining the joints between the great hull sections. By the time he had satisfied himself that they were still sound and tight, the sky had become noticeably darker. Kervenser, in response to a rap on the outside of the bridge and a few gestures, had turned on some of the outside lights. By their aid the climbers finished their work and made their way back onto the snow. Beetchermarlf appeared from under the great hull and reported his tiller lines in perfect shape. The workers at the drill had recovered several feet of core, and were taking this into the laboratory as soon as each segment was obtained, in view of the ambient temperature. Actually the local “snow” seemed to be nearly all water at the surface, and therefore safely below its melting point, but no one could be sure how true this would be deeper down. The artificial light made the sky less noticeable. The first warning of changing weather was a sudden gust of wind. The Kwembly rocked slightly on her treads, the tiller lines singing as the dense air swept past them. The Mesklinites were not inconvenienced. In Dhrawn’s gravity blowing them away would have been a job for a respectable tornado. They weighed about as much as a lifesized gold statue would have on Earth. Dondragmer, digging his claws reflexively into the dusty snow, was not bothered by the wind; but he was much annoyed at his own failure to notice earlier the clouds which accompanied it. These had changed from the fleecy cirrus perhaps a thousand feet above to broken stratus-type scud at half that height. There was no precipitation yet, but none of the sailors doubted that it would come soon. They could not guess, however, what form it would take or how violent it might be. They had been a year and a half on Dhrawn, by human measure, but this was not nearly long enough to learn all the moods of a world far larger than their own. Even had that world completed one of its own revolutions, instead of less than a quarter of one, it would not have been time enough and Dondragmer?s crew knew it. The captain’s voice rose above the song of the wind. “Inside, everyone. Berjendee, Reffel, and Stakendee to me to help with the drilling gear. First man inside tell Kervenser to stand by on engines and be ready to swing bow to wind when the last of us is aboard.” Dondragmer knew as he gave the command that it might be impossible to obey it. It was quite likely that the maintenance check might be at a stage which would prevent engine start. Having issued the order, however, he thought about it no further. It would be carried out if possible, and his attention was needed elsewhere. The drilling equipment was top priority; it was research apparatus, which was the entire reason for the Mesklinites’ presence on Dhrawn. Even Dondragmer, comparatively free of that suspicion of human intentions and motives which affected many Mesklinites, suspected that the average human scientist would value the drilling equipment more highly than the lives of one or two of the crew. The researchers had already withdrawn the bit and started inside with it when he reached them. The crank and gear box of the muscle-powered device followed, leaving only the supporting frame and guide towers. These were less critical, since they could be replaced without human assistance, but since the wind was growing no worse, the captain and his helpers stayed to salvage them also. By the time this had been done, the others had vanished inside and Kervenser was clearly impatient on the bridge above. Thankfully Dondragmer shepherded his group up the ramp and through the lock door, which he latched behind them. They were now standing on a yard-wide shelf running the length of the lock, facing an equally wide pool of liquid ammonia which formed the inboard half of the compartment. The most heavily burdened of the group climbed into the liquid grasping holds similar to those on the outer hull; others, like the captain, simply dived in. The inner wall of the lock extended four feet below the surface, and had a three-foot clearance between its lower edge and the bottom of the tank. Passing under this and climbing the far side, they emerged on a ledge similar to that at the entrance. Another door gave them ingress to the midsection of the Kwembly. There was a slight stink of oxygen about them — a few bubbles of outside air usually accompanied anything which went through the lock — but the ubiquitous ammonia vapor and the catalyst surfaces exposed at many sites within the hull had long ago proven capable of keeping this nuisance under control. Most of the Mesklinites had learned not to mind the odor too much especially since, as far as anyone knew, really small traces of the gas were harmless. The researchers doffed their suits and made off with their apparatus and the cases which had protected their cores from the liquid ammonia. Dondragmer dismissed the others to their regular duties, and headed for the bridge. Kervenser started to leave the command station as the captain came through the hatch, but the latter waved him back and went to the starboard end of the superstructure. Portions of its floor were transparent. The human designers had originally intended it all to be so, but they had failed to allow for Mesklinite psychology. Crawling about on the hull was bad enough, but standing on a transparent floor over fifteen feet or so of empty air was beyond all reason. The captain stopped at the edge of one of the floor panes and looked down gingerly. The grayish surface about the huge vehicle was unchanged; the wind which shook the hull was making no apparent impression on the snow which had been packed by two-score Earth gravities for no one knew how much time. Even the eddies around the Kwembly showed no signs of their presence, though Dondragmer had rather expected them to be digging holes at the edges of his treads. Farther out, to the limit reached by the lights, nothing could be seen on the expanse except holes where the cores had been dug and the whipping branches of an occasional bush. He watched these closely for several minutes, expecting the wind to make some impression there if anywhere, but finally shifted his attention to the sky. A few bright stars were beginning to show between the patches of scud, but the Guardians of the Pole could not be seen. They were only a few degrees above the southern horizon — much of that due to retraction — and the clouds further blocked the slanting view. There was still no sign of rain or snow, and no way of telling which, if either, to expect. The temperature outside was still just below the melting point of pure ammonia and far below that of water, but mixed precipitation was more than likely. What these would do to the nearly pure water-ice under him was more than Dondragmer cared to guess; he knew about the mutual solubility of water and ammonia, but had never attempted to memorize phase diagrams or freezing-point tables of the various possible mixtures. If the snow did dissolve, the Kwembly might get a chance to show her floating ability. He was not eager to make the test. Kervenser interrupted his thoughts. “Captain, we will be ready to move in four or five minutes. Do you want driving power?”

  “Not yet. I was afraid that the wind would cut the snow out from under us and tip us over, like backwash on a beached ship, and I wanted to be bow-on if that happened; but there seems to be no danger of it so far. Have the maintenance checks continue except for items which would interfere with a fiveminute warning for drive power.”

  “That’s what we’re doing, Captain. I set it up when your order came in a few minutes ago.”

  “Good. Then we’ll keep outside lights on and watch the ground around us until we’re ready to go again, or until the blow ends.”

  “It’s a nuisance not being able to guess when that will be.”

  “It is. At home a storm seldom lasts more than a day, and never more than an hour or so. This world turns so slowly that storm cells can be as big as a continent, and could take hundreds of hours to pass. We’ll just have to wait this one out.”

  “You mean we can’t travel until the wind goes down?”

  “I’m not sure. Air scouting would be risky, and we couldn’t go fast enough without it for
scouting to be worth the trouble, as far as the human crowd is concerned.”

  “I don’t like going so fast anyway. You can’t really look over a place unless you stop for a while. We must be missing a lot that even the human funnies would find interesting.”

  “They seem to know what they want — something about being able to decide whether Dhrawn is a planet or a star — and they pay the bills. I admit it gets boring for people with nothing to occupy them but routine.” Kervenser let that remark pass without comment, if not without notice. He knew his commander would not have been deliberately insulting, even after the mate’s slighting remark about human beings. This was a point on which Dondragmer differed rather sharply from many of his fellows, who took for granted that the aliens were out for what they could get, like any good traders. The commander had spent more time in close communication with human, Paneshk, and Drommian scientists than had almost any other Mesklinite and, having a rather tolerant and accommodating personality to start with, had become what many of the other Mesklinites regarded as soft with respect to the aliens. Discussion of the matter was rare, and Beetchermarlfs arrival forestalled it this time. He reported completion of checkout. Dondragmer relieved him, ordered him to send the new helmsman to the bridge, and fell silent until the latter arrived. Takoorch, however, was not the sort to live with silence; and when he reached the bridge lost little time in starting what he doubtless considered a conversation. Kervenser, amused as usual by the fellow’s imagination and gall, kept him going; however, Dondragmer ignored all but occasional snatches of the conversation. He was more interested in what was going on outside, little as that seemed to be at the moment. He cut off the bridge lights and all the outside ones but the lowest floods, giving himself a better view of the sky without completely losing touch with the surface. The clouds were fewer and smaller, but they seemed to be moving past quite as rapidly as before. The sound of the wind remained about the same. More stars were slowly appearing. Once he glimpsed one of the Guardians, as the Mesklinite sailors had so quickly named them, low to the south. He could not tell which it was; Sol and Fomalhaut were about equally bright from Dhrawn, and their violent twinkling through the huge world?s atmosphere made color judgment unreliable. The glimpse was brief anyway, since the clouds were not completely gone. “—the whole starboard group of rafts peeled off, with everyone but me on the main body—” Still no rain or snow, and the clearing skies made them seem less likely now, to the captain’s relief. A check with the laboratory through one of the speaking tubes informed him that the temperature was dropping; it was now 75, three degrees below ammonia melting point. Still close enough for trouble with mixtures, but heading in the right direction. “—of the islands south and west of Dingbar. We’d been ridden ashore by a storm bulge, and were high and dry with half the drift boards broken. I—” The stars overhead were almost uninterrupted now; the scud had nearly vanished. The constellations were familiar, of course. Most of the brighter stars in the neighborhood were little affected by a three-parsec change in viewpoint. Dondragmer had had plenty of time to get used to the minor changes, anyway, and no longer noticed them. He tried to find the Guardians once more, but still had no luck. Maybe there were still clouds to the south. It was too dark now to be sure. Even cutting the rest of the floods for a moment didn’t help. It did, however, attract the attention of the other two, and the flow of anecdote ceased for a moment. “Anything changing, Captain?” Kervenser’s jocular attitude vanished at the possibility of action. “Possibly. Stars are showing above, but not to the south. Not anywhere near the horizon, in fact. Try a spot.” The first officer obeyed, and a spear of light flicked upward from a point behind the bridge as he touched one of the few electrical controls. Dondragmer manipulated a pair of pull cables, and the beam swung toward the western horizon. A wail, the rough equivalent of a human grunt of surprise, came from Kervenser as the descending beam became more visible parallel to the ground. “Fog!” exclaimed the helmsman. “Thin, but that’s what’s blocking the horizon.” Dondragmer gave a gesture of agreement as he reared to a speaking tube. “Research!” he hooted. “Possible precipitation. Check what it is, and what it could do to this water ice under us.”