by Carol
Only one kind of balloon will work in an atmosphere of hydrogen, which is the lightest of all gases—and that is a hot-hydrogen balloon. As long as the fusor kept ticking over, Falcon could remain aloft, drifting across a world that could hold a hundred Pacifies. After traveling more than half a billion kilometers, Kon-Tiki had at last begun to justify her name. She was an aerial raft, adrift upon the current of the Jovian atmosphere.
Though a whole new world was lying around him, it was more than a hour before Falcon could examine the view. First he had to check all the capsule’s systems and test its response to the controls. He had to learn how much extra heat was necessary to produce a desired rate of ascent and how much gas he must vent in order to descend. Above all, there was the question of stability. He must adjust the length of the cables attaching his capsule to the huge, pear-shaped balloon, to damp out vibrations and get the smoothest possible ride. So far, he was lucky; at this level, the wind was steady and the Doppler reading on the invisible surface gave him a ground speed of 350 kilometers an hour. For Jupiter, that was modest; winds of up to a thousand had been observed. But mere speed, of course, was unimportant; the real danger was turbulence. If he ran into that, only skill and experience and swift reaction could save him—and these were not matters that could yet be programmed into a computer.
Not until he was satisfied that he had got the feel of this strange craft did Falcon pay any attention to Mission Control’s pleadings. Then he deployed the booms carrying the instrumentation and the atmospheric samplers* the capsule now resembled a rather untidy Christmas tree but still rode smoothly down the Jovian winds, while it radioed up its torrents of information to the recorders on the ship a hundred thousand kilometers above. And now, at last, he could look around.
His first impression was unexpected and even a little disappointing. As far as the scale of things was concerned, he might have been ballooning over an ordinary cloudscape on Earth. The horizon seemed at a normal distance; there was no feeling at all that he was on a world eleven times the diameter of his own. Then he looked at the infrared radar, sounding the layers of atmosphere beneath him—and knew how badly his eyes had been deceived.
That layer of clouds, apparently five kilometers away, was really sixty kilometers below. And the horizon, whose distance he would have guessed at two hundred, was actually three thousand kilometers from the ship.
The crystalline clarity of the hydro-helium atmosphere and the enormous curvature of the planet had fooled him completely. It was even harder to judge distances here than on the Moon; everything he saw must be multiplied by ten.
It was a simple matter and he should have been prepared for it. Yet somehow it disturbed him profoundly. He did not feel that Jupiter was huge but that he had shrunk—to a tenth of his normal size. Perhaps, with time, he would grow accustomed to the inhuman scale of this world; yet as he stared toward that unbelievably distant horizon, he felt as if a wind colder than the atmosphere around him was blowing through his soul. Despite all his arguments, this might never be a place for man. He could well be both the first and the last to descend through the clouds of Jupiter.
The sky above was almost black, except for a few wisps of ammonia cirrus perhaps twenty kilometers overhead. It was cold up there on the fringes of space, but both pressure and temperature increased rapidly with depth. At the level where Kon-Tiki was drifting now, it was fifty degrees centigrade below zero and the pressure was five atmospheres. A hundred kilometers farther down, it would be as warm as equatorial Earth—and the pressure about the same as at the bottom of one of the shallower seas. Ideal conditions for life.
A quarter of the brief Jovian day had already gone; the Sun was halfway up the sky, but the light on the unbroken cloudscape below had a curious mellow quality. That extra half billion kilometers had robbed the Sun of all its power; though the sky was clear, Falcon found himself continually thinking that it was a heavily overcast day. When night fell, the onset of darkness would be swift, indeed; though it was still morning, there was a sense of autumnal twilight in the air. But autumn, of course, was something that never came to Jupiter. There were no seasons here.
Kon-Tiki had come down in the exact center of the Equatorial Zone—the least colorful part of the planet. The sea of clouds that stretched out to the horizon was tinted a pale salmon; there were none of the yellows and pinks and even reds that banded Jupiter at higher latitudes. The Great Red Spot itself—most spectacular of all the planet’s features—lay thousands of kilometers to the south. It had been a temptation to descend there, but the South Tropical Disturbance was unusually active, with currents reaching fifteen hundred kilometers an hour. It would have been asking for trouble to head into that maelstrom of unknown forces. The Great Red Spot and its mysteries would have to wait for future expeditions.
The Sun, moving across the sky twice as swiftly as it did on Earth, was now nearing the zenith and had become eclipsed by the great silver canopy of the balloon. Kon-Tiki was still drifting swiftly, smoothly westward at a steady 350, but only the radar gave any indication of this. Was it always as calm here? Falcon asked himself. The scientists who had talked learnedly of the Jovian doldrums and had predicted that the equator would be the quietest place seemed to know what they were talking about, after all. He had been profoundly skeptical of all such forecasts and had agreed with one unusually modest researcher who had told him bluntly, “There are no experts on Jupiter.” Well, there would be at least one by the end of this day.
If he managed to survive until then.
THE VOICES OF THE DEEP
That first day, the Father of the Gods smiled upon him. It was as calm and peaceful here on Jupiter as it bad been, years ago, when he was drifting with Webster across the plains of northern India. Falcon had time to master his new skills, until Kon-Tiki seemed an extension of his own body. Such luck was more than he had dared hope and he began to wonder what price he might have to pay for it.
The five hours of daylight were almost over; the clouds below were full of shadows, which gave them a massive solidity they had not possessed when the Sun was higher. Color was swiftly draining from the sky, except in the west itself, where a band of deepening purple lay along the horizon. Above this band was the thin crescent of a closer moon, pale and bleached against the utter blackness beyond.
With a speed perceptible to the eye, the Sun went straight down over the edge of Jupiter, three thousand kilometers away. The stars came out in their legions—and there was the beautiful evening star of Earth, on the very frontier of twilight, reminding him how far be was from home. It followed the Sun down into the west; man’s first night on Jupiter had begun.
With the onset of darkness, Kon-Tiki started to sink. The balloon was no longer heated by the feeble sunlight and was losing a small part of its buoyancy. Falcon did nothing to increase lift; he had expected this and was planning to descend.
The invisible cloud deck was still fifty kilometers below and he would reach it about midnight. It showed up clearly on the infrared radar, which also reported that it contained a vast array of complex carbon compounds, as well as the usual hydrogen, helium and ammonia. The chemists were dying for samples of that fluffy, pinkish stuff; though some atmospheric probes had already gathered a few grams, that had only whetted their appetites. Half the basic molecules of life were here, floating high above the surface of Jupiter. And where there was food, could life be far away? That was the question that, after more than a hundred years, no one had been able to answer.
The infrared was blocked by the clouds, but the microwave radar sliced right through and showed layer after layer, all the way down to the hidden surface more than four hundred kilometers below. That was barred to him by enormous pressures and temperatures; not even robot probes had ever reached it intact. It lay in tantalizing inaccessibility at the bottom of the radar screen, slightly fuzzy and showing a curious granular structure that his equipment could not resolve.
An hour after sunset, he dropped his firs
t probe. It fell swiftly for a hundred kilometers, then began to float in the denser atmosphere, sending back torrents of radio signals, which he relayed up to Mission Control. Then there was nothing else to do until sunrise, except to keep an eye on the rate of descent, monitor the instruments and answer occasional queries. While she was drifting in this steady current, Kon-Tiki could look after herself.
Just before midnight, a woman controller came on watch and introduced herself with the usual pleasantries. Ten minutes later, she called again, her voice at once serious and excited.
“Howard! Listen in on channel forty-six—high gain.”
Channel 46? There were so many telemetering circuits that he knew the numbers of only those that were critical; but as soon as he threw the switch, he recognized this one. He was plugged into the microphone on the probe, floating 130 kilometers below him in an atmosphere now almost as dense as water.
At first, there was only a soft hiss of whatever strange winds stirred down in the darkness of that unimaginable world. And then, out of the background noise, there slowly emerged a booming vibration that grew louder and louder, like the beating of a gigantic drum. It was so low that it was felt as much as heard and the beats steadily increased their tempo, though the pitch never changed. Now it was a swift, almost infrasonic throbbing—and then, suddenly, in mid vibration, it stopped, so abruptly that the mind could not accept the silence, but memory continued to manufacture a ghostly echo in the deepest caverns of the brain.
It was the most extraordinary sound that Falcon bad ever heard, even among the multitudinous noises of Earth. He could think of no natural phenomenon that could have caused it, nor was it like the cry of any animal, not even one of the great whales.
It came again, following exactly the same pattern. Now that he was prepared for it, he estimated the length of the sequence; from first faint throb to final crescendo, it lasted just over ten seconds.
And this time, there was a real echo, very faint and far away. Perhaps it came from one of the many reflecting layers deeper in this stratified atmosphere; perhaps it was another more distant source. Falcon waited for a second echo, but it never came.
Mission Control reacted quickly and asked him to drop another probe at once. With two microphones operating, it would be possible to find the approximate location of the sources. Oddly enough, none of Kon-Tiki’s own external mikes could detect anything except wind noises; the boomings, whatever they were, must have been trapped and channeled beneath an atmospheric reflecting layer far below.
They were coming, it was soon discovered, from a cluster of sources about two thousand kilometers away. The distance gave no indication of their power; in Earth’s oceans, quite feeble sounds could travel equally far. And as for the obvious assumption that living creatures were responsible, the chief exobiologist quickly ruled that out.
“I’ll be very disappointed,” said Dr. Brenner, “if there are no microorganisms or plants here. But nothing like animals, because there’s no free oxygen. All biochemical reactions on Jupiter must be low-energy ones—there’s just no way an active creature could generate enough power to function.”
Falcon wondered if this were true; he had heard the argument before and reserved judgment.
“In any case,” continued Brenner, “some of those sound waves are a hundred meters long! Even an animal as big as a whale couldn’t produce them. They must have a natural origin.”
Yes, that seemed plausible, and probably the physicists would be able to come up with an explanation. What would a blind alien make, Falcon wondered, of the sounds he might hear when standing beside a stormy sea or a geyser or a volcano or a waterfall? He might well attribute them to some huge beast.
About an hour before sunrise, the voices of the deep died away and Falcon began to busy himself with preparation for the dawn of his second day. Kon-Tiki was now only five kilometers above the nearest cloud layer; the external pressure had risen to ten atmospheres and the temperature was a tropical thirty degrees. A man could be comfortable here with no more equipment than a breathing mask and the right grade of heliox mixture.
“We’ve some good news for you,” Mission Control reported soon after dawn. “The cloud layer’s breaking up. You’ll have partial clearing in an hour—but watch out for turbulence.”
“I’ve already noticed some,” Falcon answered. “How far down will I be able to see?”
“At least twenty kilometers, down to the second thermocline. That cloud deck is solid—it never breaks.”
And it’s out of my reach, Falcon told himself; the temperature down there must be over a hundred degrees. This was the first time that any balloonist had ever had to worry not about his ceiling but about his—basement?
Ten minutes later, he could see what Mission Control had already observed from its superior vantage point. There was a change in color near the horizon and the cloud layer had become ragged and humpy, as if something had tom it open. He turned up his little nuclear furnace and gave Kon-Tiki another five kilometers of altitude so that he could get a better view.
The sky below was clearing rapidly—completely, as if something was dissolving away the solid overcast. An abyss was opening up before his eyes; a moment later, he sailed out over the edge of a cloud canyon twenty kilometers deep and a thousand kilometers wide.
A new world lay spread beneath him; Jupiter had stripped away one of its many veils. The second layer of clouds, unattainably far below, was much darker in color than the first It was almost salmon pink and curiously mottled with little islands of brick red. They were all oval-shaped, with their long axes pointing east-west, in the direction of the prevailing wind. There were hundreds of them, all about the same size, and they reminded Falcon of puffy little cumulus clouds in the terrestrial sky.
He reduced buoyancy and Kon-Tiki began to drop down the face of the dissolving cliff. It was then that he noticed the snow.
White flakes were forming in the air and drifting slowly downward. Yet it was much too warm for snow—and, in any event, there was scarcely a trace of water at this altitude. Moreover, there was no glitter nor sparkle about these flakes as they went cascading down into the depths; when, presently, a few landed on an instrument boom outside the main viewing port, he saw that they were a dull, opaque white—not crystalline at all—and quite large, several centimeters across. They looked like wax and Falcon guessed that this was precisely what they were. Some chemical reaction was taking place in the atmosphere around him, condensing out the hydrocarbons floating in the Jovian air.
A hundred kilometers ahead, a disturbance was taking place in the cloud layer. The little red ovals were being jostled around and were beginning to form a spiral—the familiar cyclonic pattern so common in the meteorology of Earth. The vortex was emerging with astonishing speed; if that was a storm ahead, Falcon told himself, he was in big trouble.
And then his concern changed to wonder—and to fear. For what was developing in his line of flight was not a storm at all. Something enormous—something scores of kilometers across—was rising through the clouds.
The reassuring thought that it, too, might be a cloud—a thunderhead boiling up from the lower levels of the atmosphere—lasted only a few seconds. No; this was solid. It shouldered its way through the pink-and-salmon overcast like an iceberg rising from the deeps.
An iceberg, floating on hydrogen? That was impossible, of course; but perhaps it was not too remote an analogy. As soon as he focused the telescope upon the enigma, Falcon saw that it was a whitish mass, threaded with streaks of red and brown. It must be, he decided, the same stuff as the “snowflakes” falling around him—a mountain range of wax. And it was not, he soon realized, as solid as he had thought; around the edges, it was continually crumbling and reforming.
“I know what it is,” he radioed Mission Control, which for the past few minutes had been asking anxious questions. “It’s a mass of bubbles—some kind of foam. Hydrocarbon froth. Get the chemists working on—just a minute!”
“What is it?” called Mission Control. “What is it?”
He ignored the frantic pleas from space and concentrated all his mind upon the image in the telescope field. He had to be sure; if he made a mistake, he would be the laughingstock of the Solar System.
Then he relaxed, glanced at the clock and switched off the nagging voice from Jupiter V.
“Hello, Mission Control,” he said very formally. “This is Howard Falcon aboard Kon-Tiki, Ephemeris Time Nineteen Hours Twenty One Minutes Fifteen Seconds. Latitude Zero Degrees Five Minutes North. Longitude One Hundred Five Degrees Forty Two Minutes, System One.
“Tell Dr. Brenner that there is life on Jupiter. And it’s big:”
THE WHEELS OF POSEIDON
“I’m very happy to be proved wrong,” Dr. Brenner radioed back cheerfully. ‘
‘Nature always has something up her sleeve. Keep the long-focus camera on target and give us the steadiest pictures you can.”
The things moving up and down those waxen slopes were still too far away for Falcon to make out many details, and they must have been very large to be visible at all at such a distance. Almost black and shaped like arrowheads, they maneuvered by slow undulations of their entire bodies, so that they looked rather like giant manta rays swimming above some tropical reef.
Perhaps they were sky-borne cattle browsing on the cloud pastures of Jupiter, for they seemed to be feeding along the dark, red-brown streaks that ran like dried-up river beds down the flanks of the floating cliffs. Occasionally, one of them would dive headlong into the mountain of foam and disappear completely from sight.