by Ben Bova
Now we were slowly filling the envelope with hydrogen gas, sucked out of the clouds’ abundant sulfuric acid through our equipment that separated out the wanted hydrogen and released the unwanted sulfur and oxygen. On Earth hydrogen’s flammability would have been dangerous, but Venus’s atmosphere contained practically no free oxygen, so there was no danger of explosion or fire. The envelope itself was a rigid shell of cermet, a ceramic-metal composite that combined toughness and rigidity yet was lighter than any possible metal alloy.
To go deeper, we would vent hydrogen overboard and replace it with atmospheric gas: mainly carbon dioxide. When the time came to rise again, we intended to break down the carbon dioxide into its component elements of carbon and oxygen, vent the carbon overboard and let the lighter oxygen buoy us upward. Higher up we intended to dissociate the sulfuric acid molecules of the clouds again and refill the envelope with hydrogen.
We had tested the equipment for splitting the carbon dioxide and sulfuric acid molecules before we ever took off from Earth, and now, inside the globe-girdling cloud deck of Venus, we put it to work to fill the gas envelope with hydrogen.
Eager as I was to go deeper, I was perfectly happy to see that the equipment worked in Venus’s clouds. I had no desire to be stuck down at the surface with no way to come back up.
So we coasted along in the uppermost cloud deck, patiently filling the big shell above us and testing our equipment. Once in a while it seemed to me that we weren’t moving at all, that we were stuck in place like a ship run aground on a reef. All we could see out the ports was that perpetual yellowish-gray sameness. But then some strong current in the atmosphere would grab us and the gondola would tilt and groan like a creaking old sailing ship and my insides would flutter just a little bit.
I was constantly worried about Fuchs, of course, but the IAA reports on his activity showed that he was also moving cautiously. He had entered the atmosphere several hours before we did, but so far had not gone much deeper than we had. Like us, he was floating in the upper reaches of the top cloud deck, pushed around the planet by the super-rotation winds.
“He’s no fool,” Duchamp told me as we sat together in the spartan little galley. “Lars takes risks, but only when he’s certain the odds are in his favor.”
“You know him?” I asked.
She made a thin smile. “Oh, yes. Lars and I are old friends.”
“Friends?” I felt my brows hike up.
Her smile faded. “I first met him just after he had lost his business and his wife. He was a pretty desperate man then. Hurt and angry. Bewildered. Everything he had built up in his life had been snatched away from him.” She exhaled a puff of air through her nostrils, something between a grunt and a sigh.
The expression on her face told me she knew perfectly well that the man who had destroyed his company and taken his wife was my father. She didn’t have to say it; we both knew.
“But he pulled himself up again, didn’t he?” I snapped. “He’s done fairly well in asteroid mining, hasn’t he?”
Duchamp looked at me for a long silent moment, the kind of look a university professor gives to an especially dense and hopeless student.
“Yes,” she said. “Hasn’t he.”
At least, during those first days coasting through the clouds, I had an excuse to stay close to Marguerite. I was supposed to be a planetary scientist, I kept reminding myself, and even though she was a biologist we began to work together, sampling the clouds.
Marguerite’s lab was too crowded for both of us to use it at the same time, and it would have been impossible for us to work together in either her quarters or mine: Each of us had nothing more than a narrow berth with a privacy screen shuttering it. We could have both fit in either berth, but no scientific research would have been done. Indeed, I found myself wondering what it would be like to have Marguerite cupped beside me in my berth. Or hers.
But she had no romantic interest in me, that was clear. Instead, we turned the observation post up in the gondola’s nose into a makeshift laboratory where we took samples of the cloud droplets and analyzed them.
“There really is water in the clouds!” Marguerite exclaimed happily, after a long day of checking and rechecking the results of our spectral analyses.
“Thirty parts per million,” I grumbled. “It might as well be zero for all the good—”
“No, no, you don’t understand,” she said. “Water means life! Where water exists, life exists.”
She was really excited. I was more or less playing at being a planetary scientist but to Marguerite the search for life was as thrilling and absorbing as Michelangelo’s drive to create great works of art out of rough slabs of marble.
We were sitting cross-legged on the metal decking up in the gondola’s nose section because there was no room for chairs and nobody had thought to bring any cushions aboard. The transparent quartzite nose itself showed only the featureless yellowish-gray of the eternal cloud deck: It might just as well been spray painted that color for all that we could see out there. Two mass spectrometers sat to one side of us, half a dozen hand-sized computers were scattered on the deck plates, and a whole rack of equipment boxes—some gray, some black—hummed away along the bulkhead beside me.
“The presence of water,” I pointed out, “does not automatically mean the presence of life. There is a good deal of water on the Moon, but no life there.”
“Humans live on the Moon,” she countered, with mischief in the lilt of her voice.
“I mean native lunar life, you know that.”
“But the water deposits on the Moon are frozen. Wherever there’s liquid water, like under the ice crust on Europa—”
“The water vapor in these clouds,” I interrupted, jabbing a finger toward the observation port, “hardly constitutes a supply of liquid water.”
“They do to microscopic organisms.”
I had to hold back a laugh. “Have you found any?”
Her enthusiasm didn’t waver one iota. “Not yet. But we will!”
I could only shake my head in admiration for her perseverance.
“This proves that there must be at least some volcanic activity down at the surface,” Marguerite said.
“I suppose so,” I agreed.
The reasoning was simple enough: Any water vapor in Venus’s atmosphere quickly boiled up to the top of the clouds, where the intense ultraviolet radiation from sunlight broke up the water molecules into hydrogen and oxygen, which eventually evaporated away into space. So there had to be a fresh supply of water constantly replenishing the droplets. Otherwise they would have all been dissociated and blown off the planet ages ago. The source of the water most likely came from the planet’s deep interior and was vented into the atmosphere by volcanic eruptions.
On Earth volcanoes constantly blow out steam, sometimes in explosions that tear the tops off the mountains. But the water vapor they vent into the atmosphere stays in the atmosphere, on Earth. It’s not lost to space because Earth’s atmosphere gets cold at high altitudes and the water condenses and falls back as rain or snow. That’s why Earth has oceans and Venus doesn’t. Earth’s upper atmosphere is a “cold trap” that prevents the water from escaping the planet. Hothouse Venus doesn’t have a cold trap in its upper atmosphere: At the altitude where on Earth the temperature dips below freezing, Venus’s is almost four hundred degrees Celsius, four times hotter than water’s boiling point. As a result Venus can’t build up any appreciable water content in its atmosphere.
“We’ll have to go deeper to find life forms in the clouds,” Marguerite said, as much to herself as to me. “The UV absorber isn’t that much further down.”
Fuchs still worried me. Apparently he was still sailing in the clouds, as we were. But aside from his position I could get no information about him from the IAA. For a good reason: He was giving out no information, nothing but his tracking beacon and the standard telemetering data that showed his basic systems to be operating in good order. When I tried
to get details about the design of his ship or the array of sensing systems he carried, I drew a blank. Lucifer was his ship, his design, built out in the deep darkness of the Asteroid Belt, equipped according to his specifications and no one else’s. He reported the minimum required by the IAA and kept everything else to himself.
One thing I was able to do during those first days in the clouds was to begin to build up a map of the superrotation wind pattern. By recording our position from the ship’s inertial navigation system I was able to generate a three-dimensional plot of where those winds blew, a sort of weather map of Venus’s jet streams. Every time a powerful gust buffeted us and made me grab for a handhold, every time a sudden upwelling bounced us or a cold spot made us drop until my stomach crawled up into my throat, I thought to myself that at least I was getting useful data.
The winds fanned outward from the subsolar point, of course. That was where the Sun was directly overhead, blazing down on the planet’s atmosphere like a blowtorch. Venus turns so slowly, once in 243 Earth days, that the subsolar spot gets blasted remorselessly. The atmosphere rushes away from there in a gigantic heat-driven flow, setting up currents and convection cells that span the girth of the planet. I measured wind speeds of nearly four hundred kilometers per hour: We were setting a Guinness speed record for lighter-than-air vessels.
Deeper down, where the atmosphere gets thicker and so much hotter, the winds die to almost nothing. At a pressure similar to that of an Earthly ocean a kilometer or so deep, there could be nothing that we would recognize as winds, only sluggish tidal motions.
At least, that’s how the theory went.
My map of the superrotation winds was coming along quite nicely after a few days, and it made me proud to realize that I was making a real contribution toward understanding Venus. When I tried to extend my data down to a slightly lower altitude, though, in an effort to see how far down the winds might extend, the computer program glitched on me. Insufficient data, I thought, peering at the display screen.
I had coded the map with false colors, each color indicating a range of speeds. There they were, a network of jet streams all rushing out from the subsolar point, in shades of blue and green. With my VR goggles on, I saw it all in three-dimensional motion. But there was the damned glitch, a swath of red a few kilometers below our present altitude. Red should have indicated even higher wind velocity than we were in now, but I knew that was wrong. The wind velocities had to get lower as we went down in altitude, not higher. Something was wrong with the program.
I mentioned it to Duchamp and Rodriguez when we met to decide on when we would start down toward the surface.
Our conference center was the observation blister, the only place in our cramped gondola where three or four people could sit comfortably. Duchamp and I sat side by side, our chairs swivelled away from the observation ports. Rodriguez sat on the floor facing us, his back against the far bulkhead.
“All systems have performed well within their design range,” Duchamp said, tapping a manicured fingernail on the screen of her handheld computer. “Unless I hear otherwise, I declare this phase of the mission completed.”
Rodriguez nodded. “No complaints about that. It’ll be good to get out of this wind and down to a calmer altitude.”
“Calmer,” Duchamp said, “but hotter.”
“We can handle the heat.”
She smiled at him as if they had some private joke going between them.
I spoke up. “My map of the wind system keeps throwing this glitch at me.” I had brought a handheld, too, and showed it to them.
“The red indicates even higher wind velocities than we’re in now,” I said.
“That’s an extrapolation, isn’t it?” Rodriguez asked. “It’s not based on observational data.”
“No, we haven’t gone down that far, so we don’t have any data from that altitude.”
“A computer extrapolation,” Duchamp said, like an art critic sniffing at some child’s lopsided attempt to draw a tree.
“But the extrapolation is based on pretty firm meteorological data,” I pointed out.
“Terrestrial meteorological data?” asked Duchamp.
I nodded. “Modified to take into account Venus’s different temperature, pressure, and chemical regime.”
“An abstraction of an abstraction,” Duchamp said, with a that’s-that wave of her hand.
Rodriguez was staring at the smear of red at the bottom of my map. He handed the palm-sized computer back to me and said thoughtfully, “You don’t think there could be some kind of wind shear down at that altitude, do you?”
“A supersonic wind shear?” Duchamp scoffed.
“It’s not supersonic at that pressure,” Rodriguez pointed out.
She shook her head. “All the planetary physicists agree that the superrotation winds die out as you go deeper into the atmosphere and the pressure builds up. The winds get swamped by the increased pressure.”
Rodriguez nodded thoughtfully, then said slowly, “Yeah, I know, but if there really is a wind shear it could be a killer.”
Duchamp took a breath, glanced from him to me and back again, then made her decision.
“Very well,” she said. “We’ll rig for intense wind shear. Check out all systems. Make everything secure and tightened down, just as we did for atmospheric entry.” She turned to me. “Will that satisfy you, Mr. Humphries?”
I was surprised at the venom in her reaction. I swallowed once and said, “You’re the captain.”
“Good.” To Rodriguez she said, “Tommy, this means you’ll have to go outside and manually check all the connectors and fittings.”
He nodded glumly. “Yeah. Right.”
Then, smiling coldly, Duchamp turned back to me. “Mr. Humphries, would you care to assist Tom?”
“Me?” I squeaked.
“We could use the extra hand,” she said smoothly, “and the inspection is actually at your behest, isn’t it? You and your computer program.”
You bitch, I thought. Just because my computer program showed a possible problem she’s blaming me for it. Now I’ve either got to risk my neck or show everybody that I’m a coward.
Rodriguez leaned across the narrow passageway separating us and grabbed my knee in a rough, friendly way.
“Come on, Mr. Humphries, it won’t be so bad. I’ll be with you every step of the way and you’ll be able to tell your grandchildren about it.”
If I live long enough to have grandchildren, I thought. But I swallowed my fear and said as calmly as I could, “Sure. It ought to be exciting.”
It certainly was.
Basically, our task was to check all the connectors that held the gondola to the gas envelope above us. It was a job that a plumber could do, it didn’t call for any special training. But we’d be outside, in a cloud of sulfuric acid droplets that was nearly a hundred degrees Celsius, more than fifty kilometers above the ground.
Rodriguez spent two intense hours briefing me in the virtual reality simulator on what we had to do. Six main struts had to be checked out, and six secondary ones. They connected the gondola to the gas shell; if they failed under stress we would go plunging down to the red-hot surface like an iron anvil.
Akira Sakamoto, our dour life-support technician, personally helped me into my space suit. It was the same one I had used when we transferred from Truax, but now its exterior had been sprayed with a special heat-resistant ceramic. The suit seemed stiffer to me than before, although Sakamoto insisted the ceramic in no way interfered with limb motion.
Without a word, without any discernable expression on his chunky broad face, he slipped the safety harness around my waist and clicked it in place, then made certain both its tethers were properly looped so they wouldn’t trip me as I tried to walk.
Dr. Waller helped to check out Rodriguez, who got into his suit unassisted. But you had to have somebody go around to make certain all the seals were okay and the electrical lines and life-support hoses hooked up properly from
the backpack.
Marguerite came down to the airlock, too, and watched in silence as we suited up. I was trembling slightly as I wriggled into the ungainly suit, which was now sort of silvery from its new ceramic coating. But I realized with some surprise that my trembling wasn’t so much fear as excitement. I knew I should have been scared out of my bleeding wits, but somehow I wasn’t. I was going to do something, something that had to be done, and even though it was dangerous I found myself actually looking forward to it.
In the back of my mind, a jeering voice was saying, Famous last words. How many fools have looked forward to the adventure that killed them?
But with Marguerite watching me I didn’t seem to care. I thought I saw a hint of admiration in her eyes. At least, I hoped it was admiration and not amusement at the foolish machismo I was exhibiting.
“Okay, we do it just the way we did in the sim.” In my helmet earphones, Rodriguez’s voice sounded harsh and tight, definitely more tense than his usual easygoing attitude.
I nodded, then realized he couldn’t see me through the tinted fish-bowl helmet, so I said, “Roger.” Just like a real astronaut, I thought.
He went into the airlock ahead of me, cycled it down, and then went outside. Once the outer airlock hatch closed again and the ’lock refilled with ship’s air, the inner hatch indicator light turned green.
My space suit was definitely stiff. Even with the servomotors at my elbow and shoulder joints grinding away, it took a real effort to move my arms. As the airlock cycled down and the outer hatch slid open, I had to remind myself that this was going to be different from an EVA in space. This would be more like doing steelwork at the top of a tremendously tall skyscraper. If I made a false step I wouldn’t simply float away from the ship, I’d plunge screaming to the ground, fifty kilometers below.
“Take it slow and easy,” Rodriguez told me. “I’m right here. Hand me your tether before you step out.”
I could see his space-suited form clinging to the handgrips set into the gondola’s outer hull, beside the hatch. Both his tethers were clipped to its rungs.