Getting to the surface was easy. The trunk of every giant tree building was a pillar supporting the dome of the underground city, and from the trunk you could take an elevator directly to the surface, passing through more than three hundred meters of rock. When Luo Ji and Shi Qiang exited the elevator, they felt nostalgic, a feeling prompted by one thing: The walls and floor of the exit hall did not have activated display windows. Information was displayed on actual display screens that hung from the ceiling. It looked like an old subway station, and most of the handful of people in it wore clothes that didn't flash.
When they passed through the hall air lock, they were met by a hot wind blowing dusty air.
"There's my boy!" Shi Qiang shouted, pointing at a man bounding up the steps. From this distance, Luo Ji could make out only that the man was in his forties, so he was a little surprised at Shi Qiang's certainty. As Shi Qiang hurried down the stairs to welcome his son, Luo Ji turned his eyes from the reunion to the surface world before him.
The sky was yellow. He now realized why the image of the sky showing in the underground city was shot from a height of ten thousand meters, because, from the ground, the sun was only visible as a hazy outline. Sand covered everything on the ground, and cars passed by on the streets dragging dusty tails. It was another sight from the past for Luo Ji: cars that traveled on the ground. They didn't seem to run on gasoline. They came in all kinds of weird shapes, and some were new and some old, but they all shared one feature: Every car had a flat sheet installed on the roof, like an awning. Across the street, he saw an old-era building with sand-covered windowsills and windows that were either boarded up or glassless black holes. However, people were evidently living in some of the rooms, because he saw clothing hanging outside to dry and even some potted flowers on the windowsills. Though the airborne sand and dust kept visibility low, he soon located a couple of familiar building outlines farther away and knew for certain that he was in the same city where he had spent half his life two centuries ago.
He walked down the steps to the two men who were hugging and pounding each other in their excitement. Seeing the middle-aged man up close, he knew that Shi Qiang hadn't made a mistake.
"Dad, when you figure it, I'm only five years younger than you," Shi Xiaoming said, wiping tears from the corners of his eyes.
"Not bad, kiddo. I was afraid some damn white-bearded old man would be calling me Dad," Shi Qiang said with a chuckle. Then he introduced Luo Ji to his son.
"Oh, Dr. Luo. You used to be world famous," Shi Xiaoming said, as he looked Luo Ji up and down.
The three of them headed toward Shi Xiaoming's car, which was parked at the side of the road. Before they got in, Luo Ji asked about the thing on the roof.
"It's an antenna. Up on the surface, we have to use whatever electricity leaks through from the underground city, so the antennas are a little larger, and the power is only enough to run the cars on the ground. They can't fly."
The car wasn't fast, due either to the power or the sand on the road. Luo Ji looked out the window at the sandy city. He had a belly full of questions, but Shi Xiaoming and his father kept talking and he couldn't get a word in.
"Mom passed away in Year 34 of the Crisis. Me and your granddaughter were with her then."
"Oh, good.… You didn't bring my granddaughter with you?"
"After the divorce, she went with her mom. I looked up her file. She lived into her eighties and died in Year 105."
"Too bad I never met her.… How old were you when your sentence ended?"
"Nineteen."
"What did you do then?"
"Everything. At first, with no other way out, I kept up the swindles, but then I did a bit of legitimate business. After I had the money, I saw the signs of the Great Ravine and went into hibernation. I didn't know then that things would get better later on. I just wanted to see you."
"Is our house still there?"
"Land-use rights were extended past the original seventy-year period, but I only got to stay a short time before it was demolished. The one we bought later is still there, but I haven't been to see it." Shi Xiaoming pointed outside. "The city population isn't even one percent of what it was in our day. Do you know what the most worthless thing is? That house. You dedicated your entire life to it, Dad, but everything's empty now. You can live wherever you like."
Finally Luo Ji managed to seize a gap in their conversation to ask, "Do all reawakened hibernators live in the old city?"
"No way! They live outside. There's too much sand in the city. But mostly, it's because there's nothing to do. Of course, you can't go too far from the underground city, or you can't get electricity."
"What do all of you do?" Shi Qiang asked.
"Think: What can we do that the kids can't? Farming!" Shi Xiaoming, like other hibernators, no matter their age, had the habit of calling modern people "kids."
The car left the city and drove east. As the sand lessened to reveal the highway, Luo Ji recognized it as the old expressway between Beijing and Shijiazhuang, although both sides were piled high with sand now. The old buildings still stood there amid the sand, but what brought a spark of life to this desertified plain of northern China were the small oases ringed by sparse trees, which Shi Xiaoming said were hibernator settlements.
They drove into one oasis, a small residential community surrounded by a sand-break of trees that Shi Xiaoming called New Life Village #5. When he got out of the car, Luo Ji felt time flowing backward: rows of six-story apartments fronted by open space, old men playing chess on stone tables, mothers pushing baby carriages, and a few children playing soccer on the sparse lawn growing on the sand.…
Shi Xiaoming lived on the sixth floor with a wife nine years younger than him. She had entered hibernation in Year 21 due to liver cancer, but was completely healthy now. They had a four-year-old son who called Shi Qiang "Grampa."
A sumptuous lunch had been laid out to welcome Luo Ji and Shi Qiang: local farm produce, chicken and pork produced at other nearby farms, and even home-brewed alcohol. They called three of their neighbors to join them, three men who—like Shi Xiaoming—had entered hibernation relatively early, back when it was expensive and available only to rich members of the upper class or their sons and daughters. Now, gathered here after a span of more than a century, they were all just ordinary people. Shi Xiaoming introduced one neighbor as Zhang Yan, the grandson of Zhang Yuanchao, the man he had cheated back in the day.
"Remember how you made me return the money I cheated him out of? I began the day I got out, and that's how I met Yan. He had just graduated from college. Taking inspiration from his two neighbors, we went into the funeral business and called our firm the High and Deep Company. 'High,' for space burials. We shot ashes into the Solar System, and later on we were able to launch entire bodies. For a price, of course. 'Deep,' for mine burials. At first we used abandoned shafts, and later on we dug new ones, since they would work equally well as anti-Trisolaris tombs too."
The man called Yan was a little older—he looked to be in his fifties or sixties. Shi Xiaoming explained that Yan had been reawakened once before and lived for more than thirty years before going back into hibernation.
"What's our legal status here?" Luo Ji asked.
Shi Xiaoming said, "Completely equivalent to modern residential areas. We count as the city's distant suburbs, and we have a proper district government. It's not just hibernators who live here. We also have modern people, and people from the city often come out here for fun."
Zhang Yan took over: "We call the modern people 'walltappers,' because when they first get here they're always touching the wall out of habit, trying to activate something."
"So life's okay?" Shi Qiang asked.
They all said it was pretty good.
"But along the road I saw the fields you plant. Can you really support yourselves by growing crops?"
"Why not? In the cities these days, agricultural products are luxury items.… The government's actually quite good to hibernators. Even if you don't do anything, you can still live comfortably off government subsidies. But you've got to have something to do. The idea that hibernators all know how to farm is nonsense. No one was a farmer at first, but this is all we can do."
The conversation quickly turned to the history of the past two centuries.
"So what was the deal with the Great Ravine?" Luo Ji brought up the question he had long been wanting to ask.
Instantly their faces grew serious. Seeing that the meal was almost over, Shi Xiaoming allowed the topic to continue. "You've probably learned a little about it over the past few days. It's a long story. For more than a decade after you went into hibernation, life was pretty good. But later on, when the pace of economic transformation picked up, the standard of living declined by the day and the political climate constricted. It really felt like wartime."
A neighbor said, "It wasn't just a few countries. The entire Earth was like that. Society was on edge, and if you said something wrong they would say you were ETO, or a traitor to humanity, so nobody felt safe. And film and television from the Golden Age began to be restricted, and then was banned worldwide. Of course, there was too much of it to ban effectively."
"Why?"
"They were afraid of eroding the fighting spirit," Shi Xiaoming said. "Still, so long as there was food to eat, you could make do. But later on, things got worse, and the world began to starve. This was about twenty years after Dr. Luo went into hibernation."
"Because of the economic transition?"
"Right. But environmental deterioration was also a major factor. The environmental laws were there, but in those pessimistic times, the general attitude was, 'What the hell is environmental protection for? Even if Earth turns into a garden, isn't it all going to the Trisolarans anyway?' Eventually, environmental protection was seen as no less treasonous to humanity than the ETO. Organizations like Greenpeace were treated like ETO branches and suppressed. Work on the space forces accelerated the development of highly polluting heavy industry, which made environmental pollution unstoppable. The greenhouse effect, climate anomalies, desertification…" He sighed.
"When I entered hibernation, desertification was just starting," another neighbor said. "It's not what you imagine, like the desert advancing from the Great Wall. No! It was patchwork erosion. Perfectly fine plots of land in the interior began turning to desert simultaneously, and it spread from those points, like how a damp cloth dries in the sun."
"Then agricultural production plummeted, and grain reserves were exhausted. And then … and then came the Great Ravine."
"Did the prediction that the standard of living would go backward a hundred years come true?" Luo Ji asked.
Shi Xiaoming gave a few bitter chuckles. "Ah, Dr. Luo. A hundred years? In your dreams! A hundred years back from that time would have been … around the 1930s or so. A paradise compared to the Great Ravine! No way the two are the same. For one thing, there were so many more people than in the Great Depression—8.3 billion!" He pointed at Zhang Yan. "He saw the Great Ravine when he reawakened for a while. You tell them."
Zhang Yan drained his glass. Eyes blank, he said, "I have seen the grand march of hunger. Millions of people fleeing famine on the great plains through sand that blocked out the sky. Hot sky, hot earth, and hot sun. When they died, they were divided up on the spot.… It was hell on Earth. There are tons of videos to watch if you want. You think of that time, and you feel lucky to be alive."
"The Great Ravine lasted for about half a century, and in those fifty-odd years, the world population dropped from 8.3 billion to 3.5 billion. Think about what that means!"
Luo Ji got up and went over to the window. From here he could see the desert across the protective tree line, its yellow covering of sand extending silently to the horizon under the noonday sun. The hand of time had smoothed over everything.
"And then?" Shi Qiang asked.
Zhang Yan let out a long breath, as if no longer having to talk about that period of history had taken a burden off his shoulders. "After that, well, some people came to terms with it, and then more and more people did. They wondered whether it was worth it to pay so high a price, even if it was for victory in the Doomsday Battle. Think about what's more important: the child dying of starvation in your arms, or the continuation of human civilization? Right now you might think the latter choice is more important, but you wouldn't have in that day and age. No matter what the future might bring, the present is most important. Of course, that mind-set was outrageous at first, the classic thinking of a traitor to humanity, but you couldn't stop people from thinking it. And very soon the entire world thought so. There was a popular slogan back then, which soon became a famous historical quote."
"'Make time for civilization, for civilization won't make time,'" Luo Ji contributed, without looking back from the window.
"Right, that one. Civilization is meant for us."
"And after that?" Shi Qiang asked.
"A second Enlightenment, a second Renaissance, a second French Revolution … You can find all that stuff in the history books."
Luo Ji turned back in surprise. The predictions he had made to Zhuang Yan two centuries before had come to pass. "A second French Revolution? In France?!"
"No, no. That's just a saying. It was the entire world! After the revolution, the new national governments terminated their space strategies and poured their attention into improving people's lives. And then critical technology emerged: Genetic engineering and fusion technology were harnessed for large-scale food production, ending the age of weather-dependent food. From then on, the world would no longer be hungry. Everything moved quickly after that—there were fewer people, after all—and in the space of just two decades, life returned to pre–Great Ravine levels. Then Golden Age levels were restored. People had set their hearts on this road of comfort, and no one wanted to go back."
"There's another term you might find interesting, Dr. Luo," said the first neighbor, drawing closer to him. An economist before hibernation, he had a deeper understanding of the issues. "It's called civilization immunity. It means that when the world has suffered a serious illness, it triggers civilization's immune system, so that something like the early Crisis Era won't happen again. Humanism comes first, and perpetuating civilization comes second. These are the concepts that today's society is based on."
"And after that?" Luo Ji asked.
"After that came the freaky stuff." Shi Xiaoming grew excited. "Originally, the countries of the world had planned to live in peace and push the Trisolar Crisis onto the back burner, but what do you think happened? There was swift progress everywhere. Technology sped forward and broke through all the technical obstacles that had stood in the way of space strategy before the Great Ravine, one after the other!"
"That's not freaky," Luo Ji said. "Emancipation of human nature inevitably brings with it scientific and technological progress."
"After about half a century of peace following the Great Ravine, the world turned its thoughts back to the Trisolaran invasion and felt it ought to reconsider the war. With humanity's power now on a completely different plane than before the Great Ravine, a global state of war was again declared, and construction was begun on a space fleet. But unlike the first time, national constitutions were clear about one thing: Resource expenditure for the space strategy had to be kept within a specified range, and must not have a disastrous impact on the world economy and on community life. And that's when the space fleets became independent countries.…"
"You don't actually have to think about any of this, though," the economist said. "From now on, just think about how to live a good life. That old revolutionary slogan is just an adaptation of the old saying from the Golden Age: 'Make time for life, or life won't make time.' To new life!"
When they had drained their last glass, Luo Ji praised the economist for putting things so well. Now his mind had space only for Zhuang Yan and the child. He wanted to get settled as soon as possible, and then go wake them.
Make time for civilization, make time for life.
* * *
After boarding Natural Selection, Zhang Beihai found that the modern command system had evolved far beyond what he had imagined. The giant spacecraft, equal in volume to three of the largest seagoing carriers of the twenty-first century, was practically a small city, but it had no bridge or command module, or even a captain's room or operations room. In fact, it had no specific functional compartments whatsoever. All of them were identical, regular spheres that differed only in size. At any location inside the ship, you could just use a data glove to activate a holographic display, which, due to the high cost, was a rarity even in Earth's super-wired society. And at any location, so long as you had the appropriate system permissions, you could pull up a complete command console, including a captain's interface, which effectively made the entire ship, even the passageways and bathrooms, a bridge, command module, captain's room, and operations room! To Zhang Beihai, it felt like the evolution from a client-server model to a browser-server model in late-twentieth-century computer networks. With the former, you could only access the server through specific software installed on a computer, but using the latter, you could access the server from any computer on the network so long as you had the right permissions.
Zhang Beihai and Dongfang Yanxu were situated in an ordinary cabin that, like every other one, had no special instruments or screens. It was just a spherical compartment whose bulkheads were white most of the time, making it feel like the inside of a giant Ping-Pong ball. When gravity was produced by ship acceleration, any part of the spherical bulkhead could be transformed into a shape suitable for use as a chair.
For Zhang Beihai, this was another aspect of modern technology that few people had imagined: the elimination of single-purpose facilities. Only the first tendrils of this trend had appeared on Earth, but it was part of the fundamental structure of the far more advanced world of the fleet. This world was spare and simple. Devices were no longer permanently installed, but would appear when necessary at any location required. The world, made complex by technology, was becoming simple again, its technology hidden deeply behind the face of reality.
"Now we come to your first onboard lesson," Dongfang Yanxu said. "Of course, you really shouldn't be getting this lesson from a captain who's under review, but no one in the fleet is more trustworthy than I am. Today, we'll demonstrate how to launch Natural Selection and put it into navigation mode. And, in fact, so long as you remember what you see today, you'll have closed off the primary opening for the Imprinted." As she spoke, she used her data glove to call up a holographic star chart in the air. "This may be a little different from the spatial maps of your time, but it still uses the sun as the origin."
"I studied this in training, so I can read it fine," Zhang Beihai said, looking at the star chart. His memory of the ancient Solar System map he and Chang Weisi had stood in front of two centuries ago was still fresh. This chart, however, precisely marked out the positions of all celestial bodies within a radius of one hundred light-years of the sun, at a scale more than a hundred times greater than the older one.
"You don't really need to understand much. In the present state, navigation to any position on the map is prohibited.… If I were Imprinted, and wanted to hijack Natural Selection to flee into the cosmos, I'd first need to select a heading, like this." She activated a point on the map, turning it green. "Of course, we're just in simulation mode right now, because I no longer have permissions. When you obtain captain's permissions, I'll have to go through you to perform the operations. But if I really submitted this operation request, it would be a dangerous act, and you should refuse it. You should also report me."
Once the heading was activated, an interface appeared in the air. Zhang Beihai was already quite familiar with the appearance and operations from his training, but he still listened patiently to Dongfang Yanxu's explanation and watched how she brought the huge ship from complete shutdown to hibernation, then to standby, and finally to Slow Ahead.
"If these were real operations, Natural Selection would now leave port. What do you think? Simpler than spaceship operations in your day?"
"Yes. Much simpler." When he and the other special contingent members first saw the interface, they were surprised at its simplicity, and the total lack of technical detail.
"The operation is totally automatic, leaving the technical process entirely hidden from the captain."
"This display only shows general parameters. How do you see the ship's operational status?"
"Operational status is monitored by officers and noncommissioned officers at lower levels. Their displays are more complex—the further down you go, the more complicated the interface becomes. As captain and vice-captain, we must focus our attention on more important matters.… Very well, let's continue. If I were Imprinted … There I go with that supposition again. What do you think?"
"Given my position, any response would be irresponsible."
"Fine. If I were Imprinted, then I'd set the throttle directly to Ahead Four. No other ship in the fleet can catch Natural Selection under Ahead Four acceleration."
"But you couldn't do that, even if you had the permissions, because the system will only proceed to Ahead Four if it detects that all passengers are in a deep-sea state."
Under maximum propulsion, the ship's acceleration could reach 120 gs, but this exerted a force more than ten times what a human could tolerate under normal conditions. To go to maximum, they had to enter a "deep-sea state," which consisted of the cabins being filled with an oxygen-rich "deep-sea acceleration fluid" that trained personnel could breathe directly. As they breathed, it would fill their lungs and then the rest of their organs. First dreamed up in the first half of the twentieth century, the liquid was intended at the time to facilitate ultra-deep dives. Pressure was in equilibrium inside and outside of a human body filled with deep-sea acceleration fluid, meaning it could sustain high pressures like a deep-sea fish. The environment of a liquid-filled cabin in a rapidly accelerating spacecraft was like that of the deep sea, so the liquid was now being used to protect human bodies against the ultra-high acceleration of space travel. Hence the term "deep-sea state."
Dongfang Yanxu nodded. "But you should know that there's a way to get around that. If you set the spacecraft to remote control, then it will assume that no one is on board and won't perform the check. This setting is part of the captain's permissions."
"Let me try it and you tell me if I've got it right." Zhang Beihai activated an interface in front of him and began setting up remote control mode for the spacecraft, looking at a small notebook from time to time as he did so.
Dongfang Yanxu smiled at the notebook. "There are more efficient recording methods now."
"Oh, it's just habit. For particularly important things, it's always more reassuring to write them down like this. It's just that I can't find a pen now. I brought two with me into hibernation, but only the pencil was still usable."
"You've learned quickly."
"That's because the command system retains a lot of the navy's style. After all these years, the names of things haven't even changed. The engine orders, for example."
"The space fleet did have its origins in the navy.… Okay, you'll soon be receiving system permissions as the acting captain of Natural Selection. This warship is in class-A standby, or, as they called it in your time, 'fired up and ready to go.'" She extended her slender arms and turned a circle in the air.
Zhang Beihai had not been able to figure out how to perform that action using the superconducting belt. "We didn't 'fire up' in those days. But you evidently know quite a bit of naval history," he said, changing the subject from the sensitive issue that was liable to make her hostile to him.
"A grand old branch of the service."
"Doesn't the space fleet inherit that grandeur?"
"Yes. But I'm going to leave it. I plan on resigning."
"Because of the review?"
She turned to look at him, her thick black hair leaping again from the lack of gravity. "You encountered this sort of thing all the time back then, didn't you?"
"Not necessarily. But if we did, every comrade would understand, because undergoing review is one of the duties of a soldier."
"Two centuries have passed. This is no longer your time."
"Dongfang, don't deliberately widen the gap. There are similarities between the two of us. Soldiers in all ages have to bear up under humiliation."
"Are you advising me to stay?"
"No."
"Ideological work. That's the word, isn't it? Wasn't that your duty once?"
"Not anymore. I have a new duty."
She floated easily around him, as if carefully studying him. "Is it that we're children to you? Half a year ago I went to Earth, and in one hibernator district, a six- or seven-year-old boy called me a kid."
He laughed.
"Are we kids to you?"
"In our day, seniority was very important. In the countryside, there were adults who called children Aunt and Uncle because of family seniority."
"But your seniority is unimportant to me."
"I can see that in your eyes."
"Your daughter, and your wife—they didn't come with you? Special Contingent family members were allowed to hibernate, too, as far as I'm aware."
"They didn't come, and they didn't want me to go. You know, trends at the time pointed toward a very bleak future. They criticized me for being irresponsible. She and her mother moved out, and in the dead of night the day after they left, the Special Contingent received the order. I didn't even have time to see them again. It was on a late winter's night, a cold one, that I left home carrying my bags.… Of course, I'm not expecting you to understand any of this."
"I understand.… What happened to them?"
"My wife died in Year 47. My daughter in Year 81."
"They saw the Great Ravine." She lowered her eyes and remained silent for a while. Then she activated a holographic window and switched to an external display mode.
The bulkheads of the white sphere melted like wax and Natural Selection vanished, leaving them suspended in infinite space, facing the misty starfield of the Milky Way. They were now two independent beings in the universe, unattached to any world, with nothing but the abyss surrounding them. They hung in the universe like the Earth, the sun, and the galaxy itself, with no origin and no destination. Simply existing …
Zhang Beihai had experienced this feeling before, 190 years ago, when he floated in space wearing nothing but a space suit, holding a pistol loaded with meteorite bullets.
"I like it this way, where you can ignore the spacecraft and the fleet and everything outside your own mind," she said.
"Dongfang," he called softly.
"Hmm?" The captain turned around, her eyes shining with the starlight of the Milky Way.
"If the day comes when I have to kill you, please forgive me," he said gently.
She met his words with a smile. "Do I look to you like I'm Imprinted?"
He looked at her in the sunlight coming from five AU away. She was a lithe feather floating against the backdrop of the starfield.
"We belong to the Earth and the sea, you belong to the stars."
"Is that bad?"
"No. It's very good."
* * *
"The probe's gone out!"
The report from the duty officer came as a shock to Dr. Kuhn and General Robinson. They knew that once the news got out it would make waves in both the Earth International and the Fleet International, particularly since the latest observations of the probe's speed meant that it would cross the orbit of Jupiter in just six days.
Kuhn and Robinson were on the Ringier-Fitzroy Station that orbited the sun along the outside rim of the asteroid belt. Floating in space five kilometers away from the station were the most peculiar objects in the Solar System: a set of six giant lenses, the top one 1,200 meters in diameter, and the five below it slightly smaller in size. This was the latest incarnation of the space telescope, but unlike the previous five generations of the Hubble, this space telescope had no barrel, or any connecting material at all between the six giant lenses. They floated independently, the rim of each lens equipped with multiple ion thrusters that could precisely adjust the distance between them or change the orientation of the entire group. Ringier-Fitzroy Station was the control center for the telescope, but even from this close, the transparent lenses were practically invisible. When technicians and engineers would fly between them during maintenance, the universe on either side would be grossly distorted, and if they were at the proper angle, the protective iris on the surface would reflect the sunlight and reveal the entire giant lens, whose curved surface would then resemble a planet covered in bewitching rainbows. The telescope broke with the Hubble series naming convention and was dubbed the Ringier-Fitzroy Telescope, to commemorate the two men who discovered the tracks of the Trisolaran Fleet. Although their discovery had no scholarly significance, the name was fitting, because the primary purpose of this massive telescope, a joint project of the three major fleets, was the continued monitoring of the Trisolaran Fleet.
A team like Ringier and Fitzroy—a lead scientist from Earth and a head of military affairs from the fleet—had always been in charge of the telescope, and in every such team there were the same differences of opinion that Ringier and Fitzroy had. Right now, Kuhn wanted to squeeze in some observation time for his own study of the cosmos, while Robinson worked to stop him, so as to safeguard the fleet's interests. They argued about other things, too: For example, Kuhn reminisced over the wonderful way that Earth's superpowers, headed up by the United States, were leading the world, in contrast to the fleets' current inefficient bureaucracy; but every time he did so, Robinson would ruthlessly dismantle Kuhn's ridiculous historical fantasies. But the most heated argument was over the station's rotation speed. The general insisted on a slow rotation for minimal gravity, even to the point of keeping the station in an entirely weightless state with no rotation at all, while Kuhn stumped for a fast rotation and Earth standard gravity.
But what was happening now overwhelmed all of that. The probe having "gone out" meant that its engines had turned off. Two years before, far beyond the Oort Cloud, the probe had begun to decelerate, which meant that its engine had started up in a sun-facing direction, enabling the space telescope to track the probe by engine light. Now that the light had gone out, tracking was no longer possible, because the probe itself was far too small—probably no bigger than a truck, based on the wake it left crossing the interstellar dust. An object that small out on the periphery of the Kuiper Belt, no longer emitting its own light and reflecting the weak light of the distant sun even more weakly—even a telescope as powerful as Ringier-Fitzroy couldn't see such a tiny dark object so far off in the darkness of space.
"The three fleets don't know how to do anything but struggle over power. This is just perfect—the target's been lost.…" Kuhn grumbled, waving his arms for emphasis. He forgot the station was now in a weightless state, and his movements caused him to perform a somersault.
For the first time, General Robinson did not defend the fleet. The Asian Fleet had originally dispatched three light, high-speed ships to track the probe at close range, but after the dispute erupted among the three fleets over the right to intercept, the Joint Conference had issued a resolution recalling all craft to base. The Asian Fleet repeatedly protested that the three fighter-class spaceships had been stripped of all weapons and external equipment and were carrying a crew of just two people each to achieve maximum acceleration for tracking the target, and even so, they could not possibly intercept the probe. However, the European and North American Fleets were unconvinced, and insisted that all spaceships in transit be recalled and replaced by three spaceships dispatched by Earth International as a fourth party. If not for that, the fleet ships would already have made close contact with the probe and begun tracking it. Earth's ships, dispatched by the European Commonwealth and China, had not even passed the orbit of Neptune.
"Perhaps. Its engines might start up again," the general said. "It's still traveling pretty fast, and if it doesn't decelerate it won't be able to rest in solar orbit. It'll pass right through the Solar System."
"Are you the Trisolaran commander? Maybe the probe wasn't ever planning on remaining in the Solar System, but was just going to pass through anyway!" Kuhn said. Then a thought suddenly struck him. "If the engines are off, then it can't change course! Can't you just figure out where it's headed and send the tracking spacecraft to wait for it?"
The general shook his head. "That's not precise enough. It's not like an air force search in Earth's atmosphere. One miniscule error, and you'll be hundreds of thousands or even millions of kilometers off course. In such a huge area, the tracking craft won't be able to find such a tiny, dark target.… But we've got to come up with a way somehow."
"What can we do? Let the fleet figure it out."
The general turned tough. "Doctor, you've got to realize the nature of the situation. Even though this isn't our fault, the media won't care. The Ringier-Fitzroy system was, after all, responsible for tracking the probe in deep space, so a good portion of that dirty water is going to land on our heads."
Kuhn said nothing, but remained with his body perpendicular to the general's for a while. Then he asked, "Is there anything else outside Neptune's orbit that could be useful?"
"For the fleet, probably nothing. For Earth…" The general turned to ask the duty officer and soon learned that the UN Environmental Protection Organization had four large ships near Neptune, working on the early stages of the Fog Umbrella Project. The three small craft newly tasked with tracking the probe had been dispatched from those ships.
"And they're there to mine oil film?" Kuhn asked. The reply was affirmative. Oil film was a substance found in Neptune's rings. At high temperatures, it turned into a rapidly diffusing gas that then condensed into nanoparticles in space, forming space dust. It was so called because when it evaporated, it became highly diffusive, so a small quantity of the substance could form a large patch of dust, like a tiny droplet of oil spreading into an oil film of molecular thickness across a large area of water. Dust formed from this oil film had another property: Unlike other types of space dust, "oil-film dust" was not easily dispersed by the solar wind.
It was the discovery of oil film that made the Fog Umbrella Project possible. The plan was to use nuclear blasts in space to evaporate and spread the oil-film substance into a cloud of oil-film dust between the sun and Earth as a means of decreasing the sun's radiation on Earth and alleviating global warming.
"I remember there's supposed to be a stellar bomb near Neptune orbit from before the wars," Kuhn said.
"There is. And the Fog Umbrella spaceships brought along a few, too, for blasting Neptune and its satellites. I'm not sure of the precise number."
"I'd say one is enough," Kuhn said excitedly.
Like Wallfacer Rey Diaz had predicted two centuries prior when he developed the stellar hydrogen bomb for his Wallfacer plan, although the weapon would be of limited use in the Doomsday Battle, the major powers wanted it to prepare for the possible outbreak of interplanetary war between humans. More than five thousand bombs had been manufactured, mostly during the Great Ravine, when international relations grew volatile due to lack of resources, and humanity was pushed to the brink of war. When the new era dawned, the horrifying weapons became dangerous nonessentials that were kept in storage in outer space, although they still belonged to countries on Earth. A few of them were blown up in planetary engineering projects, and another set was sent into orbit in the remote Solar System with the notion that the fusion materials could supplement the fuel of long-range spacecraft. However, because of the difficulty involved in dismantling the bombs, this idea was never realized.
"Do you think it'll work?" Robinson asked, his eyes aglow. He was a little rueful that he hadn't thought up such a simple idea himself, and that Kuhn had snatched the opportunity to go down in history.
"Give it a try. It's the only thing we've got."
"If your idea works, Doctor, then the Ringier-Fitzroy Station will forever revolve fast enough to generate Earth gravity."
* * *
"It's the biggest thing humanity has ever made," the commander of Blue Shadow said, as he looked out the spacecraft's window into the pitch-black of space. Nothing was visible, but he tried to convince himself that he could see the dust cloud.
"Why isn't it lit by the sun, like the tail of a comet?" the pilot said. He and the commander were the only crew on Blue Shadow. He knew the density of the dust cloud was as thin as a comet's tail, or about the same as a vacuum created in an Earth-based laboratory.
"Maybe the sunlight is too weak." The commander looked back at the sun, which, in the lonely space between Neptune's orbit and the Kuiper Belt, looked like a large star, its disc shape only barely distinguishable. Still, even the weak sunlight could still cast shadows on the bulkhead. "Besides, a comet tail is only visible from a certain distance away. We're just at the edge of the cloud."
The pilot tried to conjure up a mental image of the thin yet gigantic cloud. A few days ago, he and the commander had seen with their own eyes how small the cloud was when compressed into a solid. At the time, the giant spaceship Pacific had arrived from Neptune and left behind five things when it stopped in this section of space. The Blue Shadow's mechanical arm first retrieved a stellar hydrogen bomb from the early days of the war, a cylinder five meters long and a meter and a half in diameter. Next it picked up four large spheres between thirty and fifty meters in diameter. The four spheres, the oil film harvested from Neptune's rings, were placed at points several hundred meters from the bomb. Once Pacific had departed the vicinity, the bomb exploded, forming a small sun whose light and heat surged into the cold abyss of space and instantly vaporized the surrounding spheres. The gaseous oil film diffused rapidly under the typhoon of H-bomb radiation, then cooled into countless tiny particles of dust, forming a cloud. The cloud had a diameter of two million kilometers, greater than that of the sun.
The dust cloud was located in the region that the Trisolaran probe was expected to pass through, according to path observations made prior to its engine shutting off. Dr. Kuhn and General Robinson hoped to precisely determine the probe's path and position by the tracks it left in the man-made dust cloud.
Following the formation of the cloud, Pacific returned to Neptune base, leaving behind three small spaceships that would track the probe closely once its wake showed. Blue Shadow was one of them. The small high-speed ship had been dubbed a "space racer." With a small capsule that could seat five as its only payload, its remaining volume was entirely occupied by a fusion engine, giving it high acceleration and maneuverability. Once the dust cloud took shape, Blue Shadow flew through the entire area to test whether wakes would be left, with quite satisfactory results. Of course, the wakes could only be observed by the space telescope more than one hundred AU distant. From Blue Shadow itself, its own wake was invisible, and the surrounding space was as deserted as it always had been. Still, after passing through the cloud, the pilot insisted that the sun looked a little dimmer, that its formerly sharp circumference had gone a bit blurry. Instrument observations confirmed the sole visual impression they had of this giant creation.
"Less than three hours to go," the commander said, looking at his watch. The dust cloud was actually a giant, thin satellite in orbit around the sun, its position constantly changing. When it eventually moved out of the space where the probe might pass through, another dust cloud would have to be created behind it.
"Do you really hope we'll catch up to it?" the pilot asked.
"Why not? We're making history!"
"Won't the thing attack us? We're not soldiers. This really ought to be done by the fleet."
Then their spacecraft received a message from the Ringier-Fitzroy Station reporting that the Trisolaran probe had entered the dust cloud and left a wake, and that precise parameters had been calculated for its trajectory. Blue Shadow was ordered to move immediately to rendezvous with and closely track the target. The station was more than one hundred AU away from Blue Shadow, meaning the message was delayed more than ten hours in transit, but the key had made an impression in the mold. Orbital calculations had even taken into account the effect of the thin dust cloud, so a rendezvous was just a matter of time.
Blue Shadow set a course in accordance with the probe's path and once again entered the invisible dust cloud, this time heading in the direction of the Trisolaran probe. It was a long flight this time, and over the course of more than ten hours, both pilot and commander grew sleepy. But the continuously shrinking distance between them and the probe kept them on edge.
"I see it! I see it!" the pilot shouted.
"What are you talking about? There's still over fourteen thousand kilometers to go!" rebuked the commander. The naked eye could not possibly see a truck at a distance of fourteen thousand kilometers, even given the transparency of space. But soon he saw it for himself: On the trajectory described by the parameters, against the silent backdrop of space, a point of light was in motion.
After a moment's thought, the commander understood: The cloud of dust larger than the sun had been unnecessary, since the Trisolaran probe had restarted its engines and was continuing to decelerate. It did not intend to skip through the Solar System. It would remain here.
* * *
Because it was only a temporary measure in the fleets, the ceremony for handing over captain's permissions on Natural Selection was a simple and low-key affair attended only by Captain Dongfang Yanxu, Acting Captain Zhang Beihai, First Vice-Captain Levine, and Second Vice-Captain Akira Inoue, as well as a special team from the General Staff Department.
Despite this era's technological development, they had still not managed to overcome the stagnation of fundamental theory, so Natural Selection's permissions transfer was done via means Zhang Beihai was familiar with: three-factor retina, fingerprint, and passphrase authentication.
Once the General Staff team had finished resetting the pupil and fingerprint data that identified the captain in the system, Dongfang Yanxu surrendered her pass phrase to Zhang Beihai: "Men always remember love because of romance only."
"You don't smoke," he replied calmly.
"And the brand was lost during the Great Ravine," she said with a trace of disappointment, and lowered her eyes.
"But the password's a good one. Not many people knew it back then either."
The captain and vice-captains exited, leaving Zhang Beihai alone to update the password and obtain complete control over Natural Selection.
"He's clever," Akira Inoue said when the door to the spherical cabin vanished.
"Ancient wisdom," Dongfang Yanxu said, watching the spot where the door had disappeared, as if trying to see through it. "We'll never be able to learn the stuff he brought from two centuries ago, but he can learn what we know."
Then the three of them remained silent and waited. Five minutes passed, clearly too long for changing a password, especially since Captain-in-waiting Zhang Beihai had come through training as the most skilled command system operator out of all the members of his Special Contingent. Five more minutes passed. The two vice-captains began swimming impatiently in the corridor, but Dongfang Yanxu remained silent and motionless.
At last the door reappeared. To their surprise, the spherical cabin had turned black. Zhang Beihai had a holographic star map pulled up on which the labels had been blocked, leaving only the twinkling stars. From the doorway, he seemed to be suspended outside the spaceship, with his interface floating alongside him.
"I'm done," he said.
"Why did it take so long?" Levin grumbled.
"Were you relishing the thrill of gaining Natural Selection?" Akira Inoue asked.
Zhang Beihai said nothing. He didn't look at the interface, but gazed off instead at a star in a distant part of the map. Dongfang Yanxu noticed that a green light was flashing in the direction he was looking.
"That would be ridiculous," Levin said, picking up from Akira Inoue. "May I remind you that the captainship still belongs to Colonel Dongfang? The acting captain is just a firewall. I'm sorry to be rude about it, but that's pretty much the truth."
Akira Inoue said, "And this state won't last for very long. The investigation of the fleet is nearing an end, and it's basically been proven that the Imprinted don't exist."
He was about to go on, but was stopped by a low gasp of surprise from the captain. "Oh, god!" she said, and the two vice-captains, following her eyes, noticed Natural Selection's current status on Zhang Beihai's interface.
The warship had been set into remote control mode, thereby bypassing the check for deep-sea state prior to Ahead Four. Outside communication had been severed. And, finally, most of the captain's settings for putting the ship into maximum propulsion were in place. With the push of just one more button, Natural Selection would head off at maximum speed to the target selected on the map.
"No, this can't be happening," Dongfang Yanxu said, her voice so low only she could hear it. It was for her own ears, in response to her earlier "god" exclamation. She had never believed in the existence of God, but now her prayers were real.
"Are you insane?" Levin shouted. He and Akira Inoue rushed toward the cabin, only to crash into the bulkhead. There was no door, just an oval-shaped section of wall that had turned transparent.
"Natural Selection is about to proceed to Ahead Four. All crew must enter deep-sea state immediately," Zhang Beihai said, every word in his solemn, calm voice lingering in the air like an ancient anchor standing in the chill wind.
"This is impossible!" Akira Inoue said.
"Are you Imprinted?" Dongfang Yanxu asked, quickly calming herself.
"You know that's not possible."
"ETO?"
"No."
"Then who are you?"
"A soldier carrying out his duty to fight for humanity's survival."
"Why are you doing this?"
"I'll explain after acceleration is complete. I repeat: All crew must enter deep-sea state immediately."
"This is impossible!" Akira Inoue repeated.
Zhang Beihai turned around and, without so much as looking at the two vice-captains, stared straight at Dongfang Yanxu. His eyes instantly reminded her of the emblem of the Chinese Space Force, bearing swords and stars alike.
"Dongfang, I said that I would be sorry if I had to kill you. There's not much time."
Then the deep-sea acceleration fluid appeared within Zhang Beihai's spherical compartment, forming into balls in the weightless environment. Each liquid globe, containing his distorted reflection along with the interface and the star map, began to combine into larger ones. The two vice-captains looked at Dongfang Yanxu.
"Do as he says. The whole ship will enter deep-sea state," the captain said.
The two vice-captains stared at her. They knew what the consequences were for proceeding to Ahead Four outside of the deep-sea protective state: The body would be plastered to the bulkhead by a force 120 times that of Earth gravity. First blood would burst out under the immense weight, spreading into a thin layer of impossibly huge, radially patterned blood stains, and then the organs would be squeezed out, forming another thin layer that would be pressed together with the body into an ugly Dali painting.…
As they left for their cabins, they issued orders to the entire ship to enter a deep-sea state.
"You're a well-qualified captain." Zhang Beihai nodded at Dongfang Yanxu. "This shows maturity."
"Where are we going?"
"Wherever we're going, it's a more responsible choice than staying here."
And then he was submerged in the deep-sea acceleration fluid, and Dongfang Yanxu could only make out a murky body through the liquid now filling the spherical compartment.
Floating in the translucent liquid, Zhang Beihai recalled his diving experience in the navy two centuries before. He had never imagined that the ocean would be so dark a few dozen meters down, but that undersea world gave him the same feeling he later found in space. The ocean was space in miniature on Earth. He tried breathing, but his reflexes made him violently cough up liquid and residual gas, and his body shifted with the recoil. Still, there wasn't the suffocation that he had anticipated, and as cool liquid filled his lungs, the oxygen it contained was supplied to his blood. He could breathe freely, like a fish.
On the interface suspended in the liquid, he saw that the deep-sea acceleration fluid was filling each occupied compartment in the spaceship in turn. The process continued for more than ten minutes. His consciousness began to blur as the breathing liquid was injected with a hypnotic component that put everyone aboard ship into a state of sleep so as to avoid damage to the brain from the high pressure and relative hypoxia generated by acceleration at Ahead Four.
Zhang Beihai felt his father's spirit alight on the spaceship from the beyond, becoming one with it. He pressed the button on the interface, issuing in his mind the command that he had been working toward his entire life:
"Natural Selection, Ahead Four!"
* * *
A small sun appeared in Jovian orbit, its bright light washing out the phosphorescence of the planet's atmosphere. Dragging the sun behind it, the stellar-class warship Natural Selection eased out of the Asian Fleet base and accelerated rapidly, casting shadows of the other warships—each dark spot big enough to contain the Earth—onto the Jovian surface. Ten minutes later, a larger shadow was flung onto Jupiter like a curtain drawn across the giant planet. Natural Selection was passing Io.
It was at this point that the Asian Fleet High Command confirmed the incredible fact that Natural Selection had defected.
The European and North American Fleets issued protests and warnings to the Asian Fleet under the initial impression that it was an unauthorized move to intercept the Trisolaran probe, but they soon realized from Natural Selection's heading that this was not the case. It was headed in the opposite direction from the Trisolaran invasion.
The various systems hailing Natural Selection gradually let up after receiving no response. The high commands began to deploy pursuit and intercept ships, although they soon realized that little could be done about the defector warship. Bases on four of Jupiter's moons possessed sufficient firepower to destroy Natural Selection, but they would not take that path, because it was quite likely that only a small minority of those on board, or even a single individual, had actually defected, and the two thousand-odd soldiers in deep-sea state were merely hostages. Commanders at the gamma-ray laser base on Europa could only watch as the small sun flew across the sky and into outer space, sprinkling Europa's vast ice sheets with light like burning phosphorus.
Natural Selection crossed the orbits of sixteen Jovian moons, and achieved escape velocity by the time it reached Callisto. Seen from the Asian Fleet base, the small sun gradually shrank, turning into a bright star that remained faintly visible for a week, as a reminder from the stars of the lasting pain of the Asian Fleet.
Since the pursuing force had to enter deep-sea state, it took forty-five minutes after Natural Selection left for those ships to launch, lighting up Jupiter with another six suns.
At Asian Fleet Command, which had stopped rotating, the commander silently faced the giant dark side of Jupiter as lightning flashed in the atmosphere ten thousand kilometers below him. Powerful radiation from the fusion engines of Natural Selection and the pursuing force had caused atmospheric ionization and lightning. The fleeting lightning strikes illuminated the surrounding atmosphere, visible at this distance as halos in constantly changing locations, turning the surface of Jupiter into a pond spattered with fluorescent rain.