The suspicion existed, and researchers considered the issue undecided. Maybe Watson, without being aware of any wrongdoing, automatically selected a landing spot that was optimal for its own existence? Of course they could prove nothing regarding the AIs, particularly since they did not know which form of existence an AI would consider to be optimal.
Jiaying pointed at the region around the South Pole and zoomed in with a spreading gesture of her fingers.
“Here we have the Tiger Stripes.” The image showed icy canyons.
“These are crevices in the ice, up to 130 kilometers long. At these crevices, it gets warmer than elsewhere on this moon, minus 93 degrees Celsius versus minus 201 degrees. The distance between them is about 40 kilometers. I am now switching to the UV range and I will increase the contrast.”
It appeared that material came out of the cracks, as if Enceladus was leaking.
She continued her presentation. “This just shows the current state. The places where most of the material is ejected keep changing, and the amount also varies with the orbit of the moon. It might look like that, but the steam does not just appear in a few spots but over the entire length of the crevices. The Tiger Stripes also grow and shift, and they do so in a few centuries. Geologically, this is a very short time.” Jiaying seems to be in her element. As a geologist, she is fascinated by these geysers, Martin perceived.
“What comes out is water vapor. There must be an enormous pressure behind it. The particles are shot into space at 1,400 kilometers per hour. This is faster than the escape velocity, so the particles do not fall back on the moon. The ice crystals then form Saturn’s E Ring. Now, I am switching back to the visible spectrum.”
The image changed and the jets became fainter.
“Where does all this come from? Just a moment...” Jiaying drew a command in the air, and the image was overlaid by a function diagram.
“Enceladus has a stone core. However, it is not large enough to provide heat, like the core of Earth.”
She moved her arm in a circle. The image zoomed out and now showed the rotation of the moons around Saturn.
“Enceladus is in a 2:1 resonance with the moon Dione, which is a bit further out. This means that for every two orbits of Enceladus, Dione finishes one. The periodic action of its gravitational pull, and the pull from the giant planet Saturn in the vicinity, massage the core of Enceladus in such a way that a lot of friction—in other words, heat—is generated.”
Jiaying clenched her hand to form a fist. Now the Tiger Stripes reappeared.
“The heat melts the ice above the core up to a certain height. This creates a liquid ocean below the ice. Minerals from the rocks are dissolved in the water. The ocean is probably rather salty. This is also supported by an analysis of deposits along the Tiger Stripes. Salts and carbon compounds were identified there. These are heavier than ice crystals and therefore they separate from the geyser streams and fall back.”
Jiaying removed the function diagram and took a short break. On the display, Enceladus sparkled like a jewel.
“The best thing," she said upon resuming, "and the reason we are here, is of course because the ELF probe found definitive signs of life. To be more precise, these were cellular structures. In a spectacular maneuver, the probe flew along the Tiger Stripes at an altitude of a few hundred meters and captured the ejected material as quickly as possible, before it could fall back down or could be destroyed by crystallization. At an ejection speed of 400 meters per second, the material would have been in the warm interior of Enceladus only a few seconds before. The measurements were clear.”
Jiaying zoomed in even more on the Tiger Stripes.
“We assume the ice here is only five kilometers thick. Further north, the thickness is 10 to 15 kilometers. Therefore, we should definitely try to land here, unless there is some important factor against it.”
Martin zoomed in a bit closer to the area. The area between the stripes only looked smooth at first glance. Cracks, fissures, plateaus, and plates dominated the picture. “There were arguments in favor of landing further north,” he said.
“Yes,” Jiaying replied, “Watson is also for it. A fresh crater would be ideal. The impact briefly melts the ice, and when it refreezes, the surface is smooth, perfect for a clean landing.”
“But.. ?” Martin interjected.
Jiaying zoomed in even further and displayed a scale.
“The local structures are predominantly level. You see? The fissure here might be about 300 meters deep. The cliff has a vertical height of 200 meters. But the plate next to it is at least 500 meters long and wide. There is more than enough space.”
For the lander and Valkyrie, an area of 50 by 100 meters will suffice. Jiaying is correct. However, we have to aim extremely well, Martin considered.
Amy spoke up, “Watson, do you have any objections to this kind of landing site?”
“The approach until t-10 seconds is 99.5 percent safe. If course corrections become necessary after t-10, the probability of a mission failure would be 80 percent,” Watson replied.
“The AI wants to say the following: ‘If we decide shortly before the landing that for some reason we want to land somewhere else, that would be bad,’” Martin explained.
The doctor abruptly asked, “What kind of reason?”
“Well, Marchenko, we will only know that when it happens,” replied Martin.
“No idea?”
Martin shook his head, but Jiaying answered for him, “Perhaps once we reach a low altitude the radar will indicate the plate we are aiming for is unstable, for instance, because of an inclusion underneath it. Or we suddenly realize we are about to land in the middle of a garden kept by an inhabitant of Enceladus.”
“Can’t we take precautions?” Marchenko stood up and stretched.
“Radar has certain limitations we can’t do anything about, certainly not from orbit, even when we are very close to the surface,” explained Jiaying.
“Any other objections?” the commander asked, looking at the crew.
“If we land in the middle of a chaotic area, a rescue mission would be difficult,” Hayato said.
“We won’t have to worry about that. A rescue mission from the spaceship is impossible. And by the time help arrived from Earth... we can forget about it.” Jiaying smiled.
“To be honest, Watson’s suggestion looks convincing to me, Jiaying,” Amy said.
“Commander, with all due respect,” Jiaying began, “we have to consider the length of the mission. Ice with an additional thickness of 2,500 meters, as to be expected near Watson’s suggested landing location, this would be 5,000 meters both ways. Four weeks at least in Valkyrie, if the ice is as clear as the geologists expect. Landing between the stripes would give us a month’s leeway.”
“Just a moment,” Hayato said. “The problem is we obviously cannot study the selected landing site.”
“Correct,” Martin answered.
Hayato seemed to have an idea. “This means we have to increase the power of the radar system. However, that appears impossible, as it is technically optimized.” Hayato had his eyes closed, as if he was concentrating on some drawing appearing in his head. “For radar to be powerful, it needs a transmitter and an antenna. We’ve got both on the ship. We use it to radio Earth. If we aim it at the landing site, would that solve our problem?”
“Certainly,” the commander said, not hesitating for long.
“Siri, can we turn the ship in such a way that the radio antenna is aimed toward the surface of Enceladus?” Amy asked.
The AI responded, “Confirmed, with certain limitations.”
“What limitations?”
“As the antenna always aims itself at Earth, the direction toward Earth must be behind Enceladus.”
“I understand, Siri. Are there any other remarks—or dangers to consider?”
“No dangers.”
“Siri, what would the procedure look like?” Amy asked.
“Fire control j
ets for two seconds, wait for seventeen seconds, fire jets again for two seconds.”
“Siri, initiate suggested maneuver. Authorization has been given by the commander.”
“Maneuver starting in three, two, one. Now.”
Martin saw that Enceladus was slowly moving out of the porthole. He had to turn away, as he would otherwise get nauseous. He checked his watch and silently counted, “Fifteen seconds, twenty seconds.” Outside of the porthole, only the starry sky could be seen.
“Rotation completed,” Siri reported.
“Good, then I am going to take care of the antenna,” Hayato said, and floated out of the room.
December 14, 2046, Enceladus
The crew could not have chosen a drearier location for their goodbyes. The garden module was now a sad sight. Because a large part of the spaceship had been exposed to a near-vacuum for several hours when the drives failed, they had mostly given up on the cultivation of the CELSS. Martin noticed something fresh and green growing in a container in the very back corner. The commander had promised she would try to restart the cultivation module during the time she and Marchenko would spend alone in the ship, so there would be fresh food available during their return trip.
The lack of growing things had one advantage, though. It was not smelly here, and the air was not hot and muggy. The module looked like a storage room that had been emptied, with strange shelves on the sides and in the middle. At the right side, as seen when one floated in from the command module, there was a centrally located hatch with a large wheel. Behind it was the passage to the lander module that up to now had been terra incognita to them. While they had trained in a replica of it on Earth, the module itself was completely virginal. Since yesterday the AI had prepared it for human occupation, meaning it was heated and had a suitable air pressure. Furthermore, all on-board computers had been started up and their software updated.
The lander module offered room for four. Its life support system was not as powerful as that of the mothership, and there was a two-month supply on board that could be stretched to three months. It used a conventional rocket engine.
The commander typed something on a number pad next to the wheel.
“All systems online,” the AI then reported. Along their year-long journey they had made jokes about why the module had been locked via a number code.
“I am sure they are keeping clones of us there, in case we don’t make it,” Marchenko had said with a diabolical grin. This does not seem completely impossible, Martin considered, since it will be an enormous PR disaster if only dead astronauts return to Earth. On the other hand, I doubt NASA can keep something like that secret for more than three weeks.
The commander now turned the wheel one rotation to the left and opened the hatch to the lander.
“Boo,” Marchenko yelled, seeming to remember his earlier joke, but no clone came out. However, no one wanted to take the first step into the lander module.
“One of you should go. Come on. After all, I am going to stay here,” the commander said after an awkward ten seconds. Finally Martin plucked up his courage. The hatch was part of a short passage, with a second hatch on the other side that was already open. Hayato entered after him. He had wrapped his son against his chest with a cloth. Then Jiaying came in. The time for their separation had not yet come. Martin wrinkled his nose. The air seems to be stale, but that cannot be. It is fresher than anything circulating in the mothership since it has not yet streamed through the lungs of anyone present. Somehow he had expected everything to be covered in dust, but the metal surfaces shone as if they had just come straight from the factory. A ship, newly built and in space, was about the least dusty place one could imagine, a paradise for allergy sufferers, at least until people moved in.
The lander module appeared small to him. It measured about two by two by three and a half meters. In comparison, the spaceship seemed huge. In this crowded space, Hayato and Jiaying would have to spend weeks while Valkyrie broke through the ice and searched for life in the ocean.
He and Jiaying had discussed for a long time what would be best for the mission. Originally, the commander was supposed to join the pilot Francesca in the drill vehicle, since she was an exobiologist. Now she would stay on board the ship with Marchenko, who was not only a doctor but also a trained pilot who had initially been assigned to steer the lander module.
Yes, Francesca can control both the lander and then afterward the drill vehicle. But what if something happens to Valkyrie and the pilot? thought Martin. Of the three remaining astronauts, Jiaying was the only one with experience as a pilot from her time in the Chinese space program. She had ambitiously climbed every step of the career ladder, and finally, as a reward, was given a spot in the Enceladus mission, to be a shining example to others.
As Hayato was more of an engineer by background, while Martin had considerable training in geology, the question of who was to sit in Valkyrie next to Francesca was soon decided—Martin Neumaier, who already had achieved such great things concerning the control of the drill vehicle while back on Earth. Initially, Jiaying had not quite agreed with this. Martin believed her, that this was not based on ambition, but on concern for him, as the journey below the ice doubtlessly would be the most dangerous part of the mission.
“Well, I won’t give a speech,” said the commander, who had been the last one to enter the lander. “But we still owe you something. We have been waiting for a suitable moment to announce the name of our son. This was for various reasons, and we ask you for your understanding.”
Martin saw there were tears in Amy’s eyes.
“I personally had hoped there would be a moment both festive and joyful, but this voyage does not seem to be made for that. And we were a bit afraid you would disagree with our choice of name, find it too solemn or even silly. But now I cannot let Hayato go without wishing him a safe return, also in the name of our son—his son. We will really miss you, Hayato, both me and our son Sol.”
Francesca, who stood next to the couple, hugged them both.
Marchenko nodded. “Good name,” he said, “very practical, nice and short.”
Jiaying first hugged Marchenko, then Amy. It was both congratulations and a farewell.
Martin shook the hands of the two people who would stay behind on ILSE. Amy’s hand felt warm and moist, while Marchenko’s was rather rough.
Hayato was about to hand the baby to Amy, but the commander rejected the gesture.
“Just a moment,” Amy said. She jumped back to the CELSS. She returned a few seconds later. She held five small bouquets of flowers in her hand. They were pansies, with small blue petals. She had secretly made her dream come true. Each of them received one of the bouquets, even Marchenko, who would stay on board the mothership with her. Hayato hugged her one last time and tearfully handed Sol to her. Martin felt warm and fuzzy inside.
Now it was time for retreating. The commander gave Marchenko a signal. He waved to them once more and then disappeared into the hatch.
“Well, get working and come back safely in a few weeks,” Amy said as she turned around and also retreated into the mothership.
Hayato wiped his eyes, went to the hatch on their side, and locked it.
“Mothership hatch locked,” Watson confirmed.
They could take the AI along anywhere. It was distributed among the computers of the ship, the lander, and Valkyrie. Its components communicated with each other on the same radio band the crew used, though not in human language but in bits, and therefore incredibly fast.
Martin sat down. The back of his seat vibrated, so he knew he had better buckle in. The monitor in front of him displayed a diagram of the lander module. At the very front was the engine that would get them safely down and bring them back again. Behind it was the habitat module where they were currently situated, surrounded by fuel tanks and storage modules. One of the storage units contained the laser concentrator that would receive the laser beam emitted by the ship and pass on the energy to Valk
yrie via a fiber-optic cable. At the very rear was a steel construction that held the bottle-shaped Valkyrie. Martin thought, Cone, cuboid, and cylinder all in a row—the lander looks a bit as if it has been assembled by a toddler.
“Like a fruit skewer,” Jiaying remarked, who obviously was also looking at the shape of the lander. Martin glanced at her. Her eyes were reddened.
Francesca, who had streaks of makeup down her cheeks, was responsible for the flight. Technically, the flight would be mostly piloted by Watson, but she could always take control if she recognized a danger for the lander.
“Uncoupling from mothership initiated,” the AI said. A sharp, metallic sound could be heard from the outside of the hull. The clamps that had been holding the lander were opening.
“Two seconds braking impulse by main engine.”
The large, cone-shaped engine burned kerosene for two seconds. Since it was aiming in their direction of flight, the impulse decelerated the lander a little bit, which was sufficient to get it into a lower trajectory. The crew carefully increased the distance between lander and mothership, meter by meter.
After about a minute, the engine ignited again briefly. Both Watson and Francesca were satisfied. Then it was time for a longer burn that brought them down to an altitude of four kilometers.
“Radar lock,” Watson now reported. The ground radar had been activated. Martin’s monitor started displaying a false-color image of the surface. Now they needed a last confirmation from the mothership. The repurposed radar antenna was scanning the intended landing site.
“All systems go. Landing site secure,” Watson confirmed.
The craft moved quietly toward the shining white moon. Martin remembered their launch from Earth, during which they had been shaken quite a bit. However, Enceladus possessed no atmosphere to speak of.
The Enceladus Mission: Hard Science Fiction Page 20