“It’s like a fairy tale,” Francesca called out. She pointed at several blue, shimmering structures that looked like starfish. “Look!” she said, “and back there. The rainbow colors on the wall—all of that was created only for us!”
She is right, Martin thought. No one before us has ever seen this beauty. And it is very unlikely someone will ever come after us.
“If a mining company on Earth only saw this,” he said. “Those must be extremely pure substances. And this is probably not the only cavity here.”
Francesca nodded. “Oh yes. Watson, delete the recording for the last three minutes. Authorization granted.”
“Deletion not possible. Authorization level too low.”
“We are offline. A higher authorization is not possible,” she said.
“Deletion not possible. Authorization level too low,” the AI repeated.
“Encode recordings made during the last three minutes with my personal password.”
“Confirmed.”
“Watson, continue ascent.”
After two hours they had covered at least half of the way. According to Watson, their chance of survival now reached 22 percent. This is barely enough to be hopeful, but the trend is in the right direction, Martin thought. In between, they had to turn back seven times, or rather, reverse out of a parking space. Going backward, Valkyrie moved much more slowly.
“Review required.”
This is what Watson said when he needed them to make a decision. If the AI does not know what to do, we have a problem. Martin knew this was the moment he had been expecting. He stayed strangely calm, maybe because he had visualized the situation often enough.
They discovered the dilemma on the screen. Above them, the channel narrowed from about 90 meters to a diameter of only a meter. Then it widened again to about six meters, but between those spots there was about 45 meters of ice, which they could not overcome with their available reserves.
“Watson, alternatives?” Martin asked.
“Tiger Stripe about 15 kilometers from here.”
On the way, the AI had already tried out all branchings. That was why they often reached a dead end. The Tiger Stripe they had chosen did not offer a way out. They could dive back down and try the next one. They had enough time, but once they reached the surface, they would be about twice as far away from the lander. They would never manage to walk for twelve hours in their suits.
“Should we try to get up there and then hope for a miracle?” Francesca looked at Martin. Her face made it obvious she did not believe in miracles. I don’t think much about them, either. Nevertheless, he nodded.
“Watson, two jets for propulsion, all other ones for melting,” Martin ordered.
He heard a rumbling sound. The jets had to turn 180 degrees. Valkyrie moved slowly upward. On the screen they did not see the work of the jets, only its result—the ice channel widened, just enough for the vehicle to fit through. It worked, but only for a few seconds.
“Battery at minimum level for ascent. Please recharge,” Watson said.
“Great advice, you stupid AI.” Francesca banged her fist against the desk. Soon afterward, a loud sound hit the vehicle like a gong. Valkyrie had hit the dome of the vent.
Martin said, “Watson, stabilize.”
“Not enough energy.”
The numbers were going haywire on the display. The flow rate of the water had tripled. The jets could not do anything about it. What is going on? Martin turned to the AI.
“Watson, explanation?”
“Insufficient data.”
What they saw was literally impossible—except that it was happening. The activity of the geysers followed a certain rhythm. They decreased when Enceladus was far away from Saturn, and increased when the moon once again approached the planet. Yet such a dramatic change in a short time cannot be related to the orbit, unless it is being affected by some cosmic force. Martin could not believe it.
“Totally impossible,” he said, shaking his head. He then thought about the being that inhabited the ocean. Is it trying to help us this way? Does it have the power to do so? It is a fascinating idea, though it does not help us. Obviously, the being has misunderstood the concept behind Valkyrie. We cannot ram through the ice like in a tank. We need energy, not speed.
Wait a moment. Speed is energy.
“Francesca, I have an idea,” Martin said. He could no longer sit still. He heard a harsh noise, as the hull was obviously scraping against the ice.
“Watson, can we use the jets as generators?” he asked.
“Correct. During drilling mode the jets partially work that way.”
“Will that work with cold water, too?”
“Correct.”
“Calculate energy generation based on current flow rate.”
“900 kilowatts.”
Martin’s idea was simple. Instead of using battery energy to drive the rotors that move the water, we will use the high-pressure water to create electricity in the jets, like in a hydro-electric power plant. Francesca was already at her console and had started to reconfigure the drill jets. They didn’t even have to turn them for this purpose, but simply use the rotors in freewheeling mode. The water that streamed through them from below made them move like millwheels in a river. That allowed them to recharge the main battery. And once it was charged, they could melt away a few meters of ice.
“Watson, calculate process cycle and duration,” Martin said.
“Projection unreliable. Expecting twelve cycles. Bottleneck can be traversed within seven hours,” the AI reported.
“Wow!” Francesca jumped up and hugged Martin. “You… genius!”
He blushed. “No, this only works due to the elevated pressure. Otherwise recharging would take much too long.”
“Then let’s hope this won’t change,” she said.
“We better not wait too long.”
Watson was responsible for implementing the cycle: collect energy, clear the passage; collect energy, clear the passage. They were moving ahead, though not quite as fast as expected. Switching from generator to drill and motor takes some time. We did not consider the inertia of the moving parts. Martin clenched his fists. He hoped the pressure would not fall back to normal. From space Enceladus must now present an impressive spectacle—the geysers have never shot up into the sky below Saturn so forcefully.
Martin sat down and then got up again. He could not bear to watch the events on the display. There, Valkyrie seemed so tiny, a blinking dot in the seemingly impermeable ice crust of Enceladus. The obstacle in front of them appeared to be so small. On the screen, it was only two or three millimeters wide, but these few pixels would mean the difference between life and death.
He had an idea as to why the water pressure had increased so much. It was not actually a speculation, but more of a wish. Maybe the being uses the piezoelectric properties of the Ice XI layer to move it forcefully far below us, like pressing a pestle into a mortar. Should I ask Watson to look for signs of this? A brief look backward, like in the biblical story of Sodom and Gomorrah? No, he would not do that. Knowing the cause did not change its effect. If there was a natural reason, the scientists on Earth would figure it out. And if Watson looked back instead of forward, even for a moment, they ran the risk of overlooking something important in their direction of travel.