Half an hour later Martin was already testing the ground under his boots, while Hayato got the explosives, the tools, and the spare oxygen tanks from the airlock in CELSS. He and Francesca had spent about 14 hours on their first trip to the volcano, and this was also the goal now. Since the details of the way were already known, Hayato and Martin would have enough time at their destination to find the best locations and set the explosives.
The first five hours seemed like a pleasant hike to Martin. He admired the view, knowing that he was enjoying it for the very last time, and he enjoyed the low gravity that allowed him to perform all kinds of tricks. The brutal fist of terrestrial gravity would press him mercilessly to the ground during the first few weeks after they were back on Earth—he hoped.
He experienced his first outside-the-lander tremor while walking, when the hard ground under his boots vibrated. It was so fascinating he did not even feel afraid. A large, egg-shaped rock in front of him suddenly split. What he anticipated—a loud cracking sound—turned out to be a low-pitched hum, like that from a giant loudspeaker. It seemed this world had an upset stomach, so to speak, and it was going to vomit large quantities in a few days, hours, or even minutes. Martin hoped to be anywhere else by that time.
“Did you feel that?” he asked Hayato.
“I even measured it. It is the strongest one so far.”
“Is it a warning sign?”
“No, I do not think so. We do not have to really start worrying until the intervals between the tremors get shorter and shorter.”
“What about the epicenter?” asked Martin.
“It is unchanged,” Hayato replied. So they were still moving toward it.
“On this slope,” Hayato said, pointing downward, “we got caught by a quake last time. I hope we can avoid that this time.”
Martin stopped one meter from the escarpment. “Great view!” he exclaimed.
“Take this!” Hayato handed him a night-vision device. “You can see the volcano a few kilometers ahead of us. It is clearly visible in infrared.”
Hayato was right. The volcano lay ahead, like... Martin could not think of a suitable comparison. What would you call a hole in the ground, oozing lava that slowly piled up into a mountain? He had always hated the required geology classes back in his school years. He moved the infrared binoculars to the side and was almost blinded. He quickly put them down. My first sunrise on a moon—and maybe my last, Martin thought. The far-away star was hardly recognizable as the sun, but its light shone incomparably stronger here than it did on Enceladus. The dance of shadows on Io made sunrise so fascinating—while the sun slowly rose, the sharply defined shadows of the mountains on the horizon changed, like in a shadow-puppet play.
“We must keep moving,” Hayato said, interrupting Martin’s admiring gaze.
They descended the slope without a hitch. Martin had forced himself to avoid looking downward. When necessary he had simply imagined himself floating down in the low gravity. He knew it was not true, but the idea managed to diminish his fear.
He was surprised when Hayato suddenly told him they were at their destination. The landscape had not changed much, except for the quite colorful ground.
“Shouldn’t we climb up there?” asked Martin.
“No, I have a different plan,” Hayato said. “Did you ever have a wart removed?”
“Not yet. For me, spitting on them always worked.”
“That will not work here, but never mind. You treat the wart at its base. The mountain, the volcano you see, consists of thick layers of lava. We could never reach the interior reservoir there.”
“So that’s why we are staying at the edge.”
“Yes. Here we are as close as possible to the highly pressurized areas, and the cap over the magma is not as thick.”
“Where do we start?”
“We want to place the C4 packs at four more-or-less equidistant points of the compass around the volcano, so we can basically start anywhere. Why not here?”
Martin used his boot to move loose material to the side.
“Just a moment,” Hayato said. “I am going to use ground-penetrating radar to find the optimal spot.”
He pulled a device from his bag and walked around in a seemingly random pattern. Martin sat down on a boulder.
“This would be good.” Hayato was a few hundred meters away. Near him, a huge rock had dug itself into the surface. He pointed at a crack running away from it. “This is perfect, in fact, a pre-made breaking point.”
Then he reached into his bag and pulled out the explosive and a detonator, putting them in place. The detonator appeared rather makeshift. Hayato noticed Martin looking and explained. “It is because of adapting for range. We should be as far away as possible when we blow this up.”
“Okay, then let’s move on to the next explosion site,” Martin said.
They went on, climbing directly across the foothills of the volcano. Hayato used his night-vision device to avoid getting into areas that were too active. Half an hour later they installed the second strip of C4, and then went on to set the third. They were keeping to their schedule.
But for the last strip of C4, Hayato had a hard time finding an optimal location.
“The ground is rather thick here,” he said, “so the explosive power would not be sufficient. I am afraid we will have to drill here.”
Well, then we are going to have to drill, Martin thought. Hayato probably brought the right device for it. And indeed, the Japanese engineer pulled something from his bag. It looked like a modified version of one of the spider robots used to close holes on the outside of the spaceship’s hull. This version seemed to be doing the opposite, though, and Martin watched the metal creature. It stood on its hind legs and then extended a stinger, in lieu of a tail, that it forced several centimeters into the ground.
“Was that all?”
“No, just wait, Martin,” Hayato said.
The spider lowered one of its hind legs into the hole, drilled a second one, and placed the other hind leg in that one.
“It’s anchoring itself in Io,” Martin said. “How cool is that?”
With the two legs secured, the spider now started working on the real hole. The drill consisted of a flexible cable that went deeper and deeper into the ground.
“How deep can it go?”
“About 30 meters, or more if you have enough cable—but for us 30 is far enough,” Martin recognized the enthusiasm in Hayato’s voice.
Martin’s boots started to tremble, then his entire body felt the subtle movement. On the ground, pebbles were jumping around. Hayato glanced at his arm display. “Even stronger than the previous one,” he said.
“And more frequent?”
“No, I do not think so.”
Martin looked at the drill robot. Red vapor was coming from its hole.
“Damn, that is sulfur—we must stop at once,” Hayato said. The spider stopped moving, but it was too late. More fumes rose from the hole, and cracks suddenly opened around the drill site, running in all directions.
“Martin, we have to leave here! Now!”
Hayato was right, and Martin took two steps backwards. But why did Hayato stop? Did he think he was immune to glowing lava? Then Martin realized why the engineer stood rooted to the spot. He had placed his bag a bit further toward the north. It was only 50 meters away, but now one of the cracks emanating from the drilling site was running right between Hayato and the bag.
“Hayato, don’t!” yelled Martin. It looked as if Hayato wanted to run toward the bag, but then he hesitated.
“The cracks, Hayato! Now! Come on!”
Hayato turned toward him. “No,” he said. “The bag there contains the last packet of C4. We still need it.”
“No, Hayato. You have to get to safety now. It is going to work with only three explosions.” At least I hope so, Martin thought.
The Japanese astronaut still seemed reluctant.
“We need you on board, Hayato. Your son
needs you.”
Hayato finally started to come, and Martin was relieved. Now he actually believed what he had said to Hayato—three explosions would relieve enough of the pressure. The important thing was to get back safely to the lander, both of them.
Seven hours later, Martin saw the oddly-shaped sausage sandwich that was their current home. Francesca contacted them via radio, and they told her what had gone wrong. The pilot responded, calm as usual. Inside the lander Martin collapsed into his seat like a dead man, yet he still could not sleep. Soon they would have the opportunity to send a message to ILSE, or to receive one from her.
They discussed again which option had the best prospect for success, and Martin was again in favor of listening. The message from Earth about Jiaying’s parents being free must have reached ILSE a while ago. Since the ship had not reacted, it might have been unwilling or unable to receive the message, it seemed. Therefore it would be useless to try it again.
When he presented his arguments to the others, both Hayato and Francesca nodded. What was up with them? Were they too tired to bicker? Perhaps they were not in the mood to think about a possible message for ILSE, and found it less stressful just to agree to listen.
The reception window would open in 42 minutes. Martin tried to get comfortable in his seat.
“If I fall asleep, please wake me in time,” he said, and Francesca at least answered with a nod.
Someone pinched his arm.
“Martin, it’s time for ILSE.”
It took him a few seconds to get his bearings. The light was so harsh he could hardly open his eyes. It was Francesca who had awakened him. The signal from ILSE would arrive soon. At least he hoped so. Martin sat up. Wouldn’t it be nice to get some good news? Surely Amy, Jiaying, and Marchenko together could take the Watson AI by surprise?
Here on Io, the three of them were awaiting a cosmic event that occurred only once every 56 hours—in its orbit around Jupiter, Io had to reach a position where their makeshift crater antenna was aiming as precisely as possible in the direction of the ship flying toward Enceladus. Since ILSE’s precise position was unknown, the moment could not be exactly predicted.
“Turn it up,” Hayato said. Francesca’s monitor displayed the current reception level.
“It’s only static, believe me.” She moved a slider, and the hiss of static filled the room. This sound was pleasing to Martin, reminding him of rain pattering against a window back on Earth. Right now, if only he were sitting by a fireplace with a glass of red wine, the mood would be perfect. Boy, oh boy, he thought, you are starting to fantasize again.
There was a crackling sound.
“There—I heard something!” exclaimed Hayato, but it returned to just the static hiss.
Two minutes later, Martin thought the static was fading. The hissing became softer. Was it only his hearing, adapting to this particular noise? “Do you notice it too?”
“Yes, a static signal is gradually cutting in—maybe a position report by ILSE.”
The spaceship broadcast on different frequencies. On one of them, ILSE automatically sent a repeating ‘I-am-here’ signal.
“The axis is correct for one thing,” Martin said, “Are you searching all the standard frequencies?”
Francesca nodded. All data were being recorded in parallel, so they would not have to worry about missing something.
“… ILSE, this is the commander.”
“YES!” exclaimed Hayato.
Martin’s could feel his heart begin to race.
“We are on the way back to Io. Estimated time of arrival, seven days.”
ILSE would pick them up. They would not have to die on this moon. Martin felt an infinite sense of relief. What about Jiaying? Was everyone okay?
“We were able to reset the AI by rebooting all systems. Everyone is doing fine.”
How clever of Amy, Martin thought. The way she phrased the message, Earth won’t find out about Marchenko’s existence. In a few hours, the message from ILSE would reach their home planet.
Everyone was doing fine—he had heard it. Did that include Jiaying? Martin was glad he was not in her shoes. They would soon meet again. Did he look forward to it? Martin was undecided. She had betrayed them all. Yes, she was being strong-armed, but surely there was an alternative course of action? Maybe she truly had no choice. Could he really judge the situation? Was it up to him to evaluate her behavior? Martin pictured Jiaying the way he had last seen her—controlled, ambitious, but with a passionate inner fire. Martin suddenly felt warm all over. Yes, he was looking forward to seeing her again.
“Requesting status report.”
Those were Amy’s last words, and then the message repeated. The three people on ILSE were unaware of the powerful antenna Martin had built on Io. They would assume the crew was marooned on the moon without being able to receive messages. Nevertheless, they recorded and sent this short loop. Very foresighted, Martin thought.
“What do you think?” Hayato was the first to break the silence.
“Another week… we can make it,” Francesca said, and she jumped up, ran to Hayato, and hugged him. Then it was Martin’s turn. “Guys, we are going to make it, do you realize that?” she said excitedly. “We have a realistic chance to get back home!”
“That is, if the volcano plays along,” Martin said. He was glad Jiaying and the others were fine, but he did not yet dare dream of Earth. Right afterward, they heard a loud cracking sound. The door to CELSS suddenly opened, and the ground, and their temporary ‘home,’ vibrated again.
“We should leave that door open from now on,” Hayato said, otherwise ignoring the tremor.
That day, Io shook them three more times.
On the evening of the 23rd, Martin placed five marks on his little list.
Only 24 hours later he counted eleven new marks. He pointed it out to Hayato.
“Yes, I noticed it too. But what do you want to do?”
The engineer was right. Martin shrugged in reply. All they could do was wait and see. ILSE had been moving toward Enceladus for a week, so it could not return in less than four days. It was a simple matter of physics, of positive and negative acceleration. There was no question, Martin would have preferred to have a safe harbor in orbit now.
On April 25, a quake caused the first serious damage to the lander. A filter unit of the life support system was torn from the wall, flooding the floor with a stinking liquid. The system had a redundant structure, so they did not have to fear for their lives—yet! Furthermore, there were two more filter units in the CELSS, but the stench was hellish. If they could only air out the place! They actually considered venting the lander, but that would waste valuable resources. Stinking air was still better than none at all.
On the afternoon of the 25th they sent a message to ILSE describing their current problems. It was to be their last one, for on the evening of the same day a quake destroyed the antenna’s receiver. At least that was Martin’s theory, when after the 21st tremor of the day the signal disappeared. They wondered whether to check on the antenna, but then decided against it. During an EVA they would run the risk of being caught in a quake, and ILSE should soon be within radio range of the lander.
April 26th began with two hard quakes in short succession.
“We have to talk about the possibility of ILSE not being here in time to pick us up before it gets dangerous down here.” Hayato spoke the sentence quite coolly—Martin could hardly believe he was really being this calm. Since the double quake, Martin’s left pinky finger had started to twitch uncontrollably. It must be my nerves, he decided. He pushed the hand under his thigh, but then saw Francesca noticing the movement. She said nothing.
“The frequency of quakes has significantly increased, as you certainly must have noticed,” Hayato said, “and so has their amplitude.”
“Can you make a prediction?”
“Not really, Francesca. We do not have a complete model of Io’s tectonic activity. All I have are estimates and cal
culations based on data from Earth. But we know Io has a very different internal structure. Even the source of its tectonics is quite different.”
“Meaning what?”
“The tremors will increase. Eventually, one of them will tear open the cover of the magma chamber enough to cause an explosion.”
“Then we should do something,” Martin said.
“No, then it would be too late,” Hayato said, shaking his head. “We have to initiate a reduction of pressure beforehand, so we need to detonate the explosives before the eruption.”
“How do we do that without knowing when the volcano will explode?”
“Our detonations will trigger the explosion.”
It sounded simple, and Martin had actually suspected it, but it still gave him goosebumps. “So we blow up the bomb we are sitting on?” Martin wanted to be absolutely sure.
“If you want to put it that way...”
“From what distance should we trigger the detonators?”
“The strong magnetic fields here interfere with radio signals, so it should definitely be less than 50 kilometers.”
The distance to the volcano was about 35 kilometers, and Martin considered their options. They could trigger them from here or from space—as long as they stayed within a radius of 50 kilometers around the volcano. It would be better to be a bit closer to make sure the detonation signal actually got there.
“But the plume would reach several hundred kilometers high, wouldn’t it?” he asked.
“Yes. We should expect that, even with reduced pressure,” Hayato answered.
“Then at least in the beginning this would seem to be the safest spot. The stuff will need a while before coming down again. At that moment, though, we had better already be off.”
The Io Encounter: Hard Science Fiction (Ice Moon Book 3) Page 23