The Enceladus Mission: Hard Science Fiction
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Martin nodded again.
“That’s quite normal. Once you get used to the cold it is not so bad. You have to work your way into Antarctica.”
Martin obviously still looked skeptical.
“I did not want to believe that on my first day, either. Just turn around! There is really unlimited freedom here as this continent belongs to no one and everyone. I think you can see that in the landscape.”
Martin only saw the desolation of an icy desert, with mountains in the background, also covered in ice. Doubtlessly fascinating in a morbid kind of way, but he preferred more inviting regions.
“Believe me, there is no landscape on Earth that is so honest. If you make a mistake, the cold has got you by the balls. If you make two mistakes, you die. The only environment that resembles Antarctica in this aspect is the cosmos.”
Pronounced by the Pole, the word sounded particularly harsh. Martin had no intention of visiting this cosmos for an extended period, as his short trip into space had been enough.
“Come on, we have to hurry, as the others are waiting for us.” Tadeusz placed a hand on Martin’s shoulder and gave him a symbolic nudge.
How did I ever come up with the stupid idea of testing the software directly on the console of Valkyrie? Couldn’t they just have established a laser link instead? It's the fault of Mr. Stone, Martin decided, Mr. Stone Jr., who had casually mentioned a short stroll to the test site. Valkyrie could not be tested directly at the polar station because the station was built on solid ground. The ice drill was supposed to work its way into the ocean beneath the ice and then go diving for a while. Since it did not matter whether the water was deep, they had selected a location about three kilometers north of the station. In other regions that would have been a 40-minute walk, but here it required a minor expedition. The station’s three snowmobiles had driven ahead, carrying supplies and tools.
Martin only realized they had arrived when, lost in thought, he collided with the Polish researcher, who had suddenly stopped. Martin apologized to Tadeusz, who turned around and smiled at him.
“It is getting better already, isn’t it?”
Martin did not have the heart to shake his head. He tried to say something, but it felt as if his facial muscles were frozen. However, he did feel there was a warm spot, right above his heart.
Once inside, the rest of his body needed a quarter of an hour to reach its normal temperature again. The lab tent and the common tent were well-heated. Stone Aerospace had transported, via ship, a small diesel power plant that now provided the laser in Valkyrie with electricity, and also supplied heaters, computers, and other things. Mr. Stone had greeted him in person right after his arrival, though Martin could barely remember this.
Nevertheless, the trip had been worth his while, at least for the computers. Stone must have invested quite a bit of money for this, he speculated. Martin could have run a 1-cubic-kilometer cell simulation of Antarctic circulation for the coming two weeks. At NASA he would have had to reserve time on a supercomputer first. Currently, Valkyrie was Stone’s only project, and he seemed to be betting the entire company on it. A drilling robot successfully used on Enceladus could also be sold on Earth.
After his body had reached a more bearable temperature, Martin sat down and rolled his office chair a bit closer to the desk adjusting the seat to the right height. If he used the wrong posture, he soon knew it by the pain in his right wrist. He pulled the keyboard a bit closer, stretched his legs, and launched the debugger. I probably stand no chance of succeeding at this task. Valkyrie and its control software have been in development for over 20 years. The various programmers have documented the code very well, indeed. I should congratulate Stone for it the next time I see him, since this is not always the case. Yet software has the natural tendency to become more complex. In the beginning, there is a routine that is supposed to generate a clearly defined result under specific circumstances. The programmer tests the routine under these circumstances. If he is clever, he also checks what will happen under different ones, if he has enough imagination to visualize different circumstances.
No one can foresee the future, though. Three years later, the module might have to work with subroutines that did not exist when it was created. Five years later, the original conditions for which it was written might no longer exist, but as the first programmer had tested it well, no errors appeared even under different requirements—at least not yet. At some point, reality will test the hitherto unknown limits of the programming, and then a crash will occur. Martin was supposed to help ensure this crash did not happen at a depth of over 3,000 meters.
In the case of a short, primitive program, he would have gone through every line of code. He would have checked which command led to which behavior at which time, whether variables were neatly defined, and whether memory was freed up in time. However, for software of this complexity, such an approach was not efficient. It would have taken Martin months to go through tens of thousands of lines of code, and Valkyrie was supposed to start digging into the ice cap tomorrow.
Of course, Stone’s programmers had already run all sorts of tests.
The danger consisted in a kind of tunnel vision. Martin wondered, Would they blindly trust the programs in cases that appeared too trivial to them? For this reason he had brought along his own testing tools. These simulated an actual mission for the Valkyrie software by transmitting data to it via the interfaces defined by the programmers, known as ‘APIs,’ or Application Programming Interfaces. Then Martin could follow the reaction of the software live in the debugger. Working in this so-called sandbox was also faster, since it could try out various scenarios much more rapidly than in real life. He did not have to wait until rear jet 1 had actually started up; he could cancel the test as soon as the correct start command for the jet had been issued.
Martin started his software tests at the critical moments, and thought, what would happen once Valkyrie had finished making its way through the ice? At that point, a number of components had to change their function. The jets no longer could discharge the heated water toward the front for drilling, but now served as the drive. If the command to switch came too late, they would press Valkyrie from below against the ice cap. The drill vehicle, therefore, must recognize exactly when that critical moment occurred. The software also had to take irregularities into account, such as local bubbles in the ice that might briefly give the impression the goal had been reached. Martin systematically changed the input parameters. For the software, this looked as if it was turning hot and then cold, as if Valkyrie was first being crushed by the ice, and then seemed to be swimming in a viscous slush of ice and water. In all cases, the software reacted in an optimal fashion. This did not mean the passengers would have always survived, however. The drill vehicle had been built with certain safety margins, and if these were exceeded, the crew could not be saved. Nevertheless, this reflects the excellent work Stone’s programmers have done, Martin recognized. The software extended the safe area, which had already been defined twice as large as to be expected in reality, by another 20 percent, as it reacted in the right way to compensate. I really will have to congratulate Stone.
Martin worked intensively for two, three, four hours. He was lost in his simulations and anxiously watched when Valkyrie succeeded against the environment—which he had programmed to be particularly aggressive—and when it failed. Therefore, he was all the more shocked when a warm hand touched his shoulder. His body suddenly jerked, and he almost fell off his chair.
A sonorous warm voice with a Southern European accent softly spoke, “Oh, sorry.” Martin quickly got up.
“No, just go on, I did not want to interrupt you.” The woman, maybe in her late forties, as indicated by her laugh lines, was a bit taller than he. She had long, dark hair, full lips, and broad shoulders. Martin lowered his gaze and noticed the name tag sewn to her uniform read Francesca Rossi. He was feeling hot, plus he was angry at himself, but he could not come up with an answer.
/> “I, uh...”
“It’s okay, just sit down again. I really did not want to disturb you. They told me you were testing Valkyrie, and as it will be launched tomorrow with me inside...”
“You are the pilot?” Martin sat, as he remembered the crew list. He did not know where he had seen her, even though the image was clear in his mind.
“Yes. Though we are going to be more like passengers tomorrow,” replied Francesca, “if I understand the mission description correctly.”
“I... I don’t know. I just arrived today and spent the whole time online in the simulations.”
“It seems our superiors suddenly lost their courage—or is there something else behind the fact they hired you for this task?” Francesca looked at him with genuine interest. He could well understand her curiosity. If I were to be shot into the ice tomorrow, sitting in a large steel tube... Martin did not even want to imagine this scenario.
“Everything is okay,” he said. “Valkyrie only failed in two-thirds of the test cases.” Francesca stared at him with open mouth and large eyes.
“What I meant to say—it worked excellently, way beyond its defined operating range.”
“So everything is fine?” Francesca asked.
“Well, you could say it that way. As long as...” Martin did not finish his sentence.
“I understand. I am relying on you.” Francesca turned around and apparently wanted to leave.
“Is this your first mission in the ice?” He was surprised at himself for asking this question. The Italian woman looked at him.
“It is indeed. I am actually a fighter pilot.”
“So you have probably seen a lot.” I do not envy her. It's enough to read about the horrors of the modern world while in my nice, warm office, he decided.
“My last combat mission was already three years ago, fortunately. Turkey.” Martin remembered the Islamist coup that had happened then. “It... felt strange to push the button—just like in a computer game. The AI is doing most of the work.”
“So why are you doing this?” After asking this question, he became self-conscious. Maybe I was too personal. I really don't know this woman. Francesca looked at him, her eyelids trembling slightly.
“That feeling, when the plane starts up with you inside. Sure, there is the AI, but I can still press the big red button. Where else can we still reach our limits these days? You are protected by software everywhere...”
“That is your reason for Valkyrie?”
“I certainly agreed right away to do it.”
Martin turned away. He was feeling hot, and his face was probably red. A sense of unease drifted through his mind. What would happen if I made a mistake in my simulations? Can I really be sure? His work had never decided so directly whether a human being lived or died. He couldn’t sit still—he got up and wandered aimlessly through the room. He could feel Francesca’s gaze follow him.
“Don’t worry,” he finally said. “I am only a little bit confused. Normally, I just sit in a small office. There's too much action here for my taste, but the Valkyrie device is safe.” He realized he was trying to reassure himself by doing this, but it worked. He finally managed to sit down and look at Francesca again.
“Well, that makes me feel better,” the pilot said with a grin, as if she had seen through him. “See you tomorrow.” She turned around and left the room.
June 29, 2045, Antarctica
Three hundred meters down, the ice was as dark as outer space without a sun. Martin looked at the monitor. It showed him several perspectives of a scene the crew of Valkyrie could also see on a similar display. Windows were useless in a drill vehicle, so Valkyrie did not have any, even though it would move like a submarine after getting through the ice layer. Its hull was made of special steel and had to withstand high pressure, heat, and cold. Therefore, any gap in the structure would present a safety risk.
The voices of the two people on board sounded calm and clear in Martin’s ears, like they were standing right next to him. Martin was not surprised by the sound quality. This was an advantage of the fiber-optic cable that not only provided Valkyrie with energy from the laser, but also allowed for excellent data transmission. I can't imagine how Francesca and Devendra stay so calm, he thought. While Francesca was an experienced fighter pilot, Devendra, an Indian Sikh, seemed at peace with himself in a way Martin had never experienced with anybody. And yes, Valkyrie was not moving through deep ice for the first time, and after all, it had survived his own simulations.
This did not change the reality that the crew was inside a steel cylinder with the diameter of a small bathroom, without a direct view of the outside, or the chance to simply surface. Valkyrie wasn’t a submarine, but a unique vehicle stuck deep in the ice of Antarctica. The canal it had drilled had long ago frozen solid behind it. If for some reason the hot water drill failed, they could not simply pull on the cable to return the vehicle to the surface. Valkyrie would somehow have to free itself on its own. There was a safety measure in place where it should break through beneath the ice layer and then maneuver near the bottom of the ocean to reach open water. Here, this was a relatively easy exercise, and they would reach their goal after 600 meters. It was vastly different on Enceladus, because there they would have to get through five to eleven kilometers of ice. They would only know after their arrival exactly how many kilometers they would have to traverse.
The launch did not appear to be spectacular. Valkyrie simply lay flat on the ice, with its tip pointing toward the South Pole. The only sound came from the refrigerator-sized module housing the laser. The laser unit itself was silent, but its ventilation made a hissing noise. Martin also heard the dull droning of the diesel generators from within their containers—almost a small power plant in itself, since Valkyrie needed up to five megawatts of power. Thick cables transported the energy from the containers back to the laser. The shielding was meant to protect the cable from damage, since without electricity there would be no working laser, and without laser light, Valkyrie would be stranded in the ice. The diesel generators would not be part of the flight into space; a spacecraft could hardly carry that much fuel.
From a distance, the cable running from the laser unit to Valkyrie seemed alarmingly thin. It was nicknamed ‘the umbilical cord,’ and for good reason; through this bundle of optical fibers, with a diameter of less than a millimeter, the laser sent the energy that was supposed to clear a path for Valkyrie. At the stern of the vehicle was a drum that could unspool several kilometers of this cable. An electric cable of that length would have hardly fit into a drill vehicle of this size.
The two test pilots had waved goodbye to those present and then crawled into a hatch at the end of the steel cylinder. There really wasn’t enough space to enter it upright. Later Martin saw them on his monitor as they sat in their chairs, which could be rotated up to 90 degrees.
Valkyrie initiated the launch procedure with the push of a button. The automatic control had activated the laser. It shot its ray at light speed through the kilometers-long cable. At the end of the cable, in the bow of Valkyrie, it stimulated a heating element that began to melt ice and vaporize the water. Valkyrie utilized this hot steam in two ways; first, like a small power station, to generate electricity for the on-board instruments, and second, to flow through eight nozzles at the bow to create a path through the ice for the vehicle. Unlike a metal drill, this drill jet never wore out. So long as it was supplied with laser energy, the vehicle would continue on its way. Three further jet drives, moveable and located two meters behind the bow, allowed for selecting the direction of drilling. They pressed the prow of the vehicle, which always swam in a hot soup, in the desired direction. And, once Valkyrie had broken through the ice, they would be responsible for propulsion.
The launch commenced from a horizontal position, and while the bow got very hot, the vehicle gradually sank into the ice with its tip forward. The Stone engineers had come up with this simple technique soon after the failed test of year 20
38. It was impressive that Valkyrie eventually reached the desired 90-degree position without any control input, simply because it followed the path of least resistance. Martin could get enthusiastic about such clever methods; he knew software written by humans was always error-prone.
After only 45 minutes Valkyrie had reached a depth of 300 meters, where Martin was now watching the crew. This stop had been planned so they had enough time to check the course of the hole and the condition of the machinery. Martin’s help was not needed for this. The check wasn’t actually necessary, either, as the software would have issued an alert in case of any deviation. However, they were not going to blindly trust the programming.
Martin had interlaced his fingers and was twiddling his thumbs. One minute, two minutes, three minutes passed. He wondered, did my simulations take such a consciously triggered full stop into account? Probably not. He had particularly concentrated on catastrophes caused by the outside world. Suddenly, Martin shivered. Why did I not ask for today’s mission plan? He shook his head. I probably should not worry at all. Nevertheless, he would be even more careful next time, by a whole order of magnitude.
“Valkyrie to Flight Director, when is it going to continue?”
Francesca had asked this in such a way that an unspoken ‘finally’ could not be ignored.
“FD to Valkyrie, just one moment.”
This was the voice of Stone, who seemed to have personally taken over the role of Flight Director. It was very unusual that during a NASA program an external person served as FD, even though he was the inventor of this technology.
“FD to Valkyrie, radar showing an obstacle at two o’clock, X minus 20.”
“Confirmed. Is this a problem?” Francesca replied.
Was Stone getting overly cautious? Martin wondered about this, and pulled up a window with the radar on his display. Valkyrie should be able to get around this obstacle quite easily, should this even be necessary. They would see once they got closer. There would still be enough time for an evasive maneuver.