The main difference from a Common Era city was that the entire world seemed to be constructed out of metal. The buildings were metallic, and the inside of the bus seemed to be mostly metal as well. She saw no plastic, and no composites either.
Cheng Xin paid the most attention to the other passengers on the bus. Across the aisle sat two men, one of whom dozed with a black briefcase on his lap, while the other wore yellow work overalls with black oil stains. Next to the man’s feet was a tool bag, and some instrument Cheng Xin did not recognize poked out of it: It resembled an ancient power drill, but was translucent. The man’s face showed the exhaustion and numbness of someone who performed physical labor. The last time Cheng Xin had seen such an expression was on the faces of migrant laborers in Common Era cities. In front of her sat a young couple. The man whispered something in the woman’s ear, and the woman giggled from time to time while spooning something pink out of a paper cup—ice cream, since Cheng Xin picked up the sweet fragrance of cream, no different from her memory of more than three centuries ago. Two middle-aged women stood in the aisle—they were of a type familiar to Cheng Xin: The drudgery of everyday life had ground away their glamour, and they no longer took care with their appearance or were fashionable. Women like that had disappeared during the Deterrence Era or the Broadcast Era. Back then, women always had smooth, delicate skin, and no matter how old they were, they looked beautiful and refined, appropriate for their age. Cheng Xin eavesdropped on their conversation:
“You got it wrong. The morning market and the evening market have similar prices. Don’t be lazy. Go to the wholesale market on the west side.”
“They don’t have enough, and they won’t sell at wholesale prices anyway.”
“You have to go later, after seven or so. The vegetable vendors will be gone, and they’ll sell at wholesale prices.”
She overheard snippets of other conversations in the bus as well.
“The city government is different from the atmospheric system, much more complicated. When you get there, pay attention to the office politics. Don’t get too close to anyone at first, but don’t hold yourself apart either.” … “It’s not right to charge separately for the heat; that should have been included in the electric bill.” … “If they had subbed for that fool earlier they wouldn’t have lost so badly.” … “Don’t be so disappointed. I’ve been here since the city was built, and how much do you think I make every year?” … “That fish is no longer fresh. Don’t even think about steaming it.” … “The other day, when they had to make an orbital adjustment, Park Four’s water spilled again and flooded a large area.” … “If she doesn’t like him, he should just give up. All that effort is just going to be wasted.” … “That can’t be authentic. I don’t even think it’s a high-quality imitation. Are you kidding me? At that price?” …
Cheng Xin’s heart felt warm and content. Ever since she had awakened for the first time during the Deterrence Era, she had been searching for this feeling. She had thought she’d never find it. She absorbed the conversations around her as though slaking a thirst, and didn’t pay much attention to Cao Bin’s narration of the city.
Space City Asia I was one of the earliest to be built as part of the Bunker Project. It was a regular cylinder that simulated gravity with the centrifugal force generated by spinning. With a length of thirty kilometers and a diameter of seven kilometers, its usable interior surface area was 659 square kilometers, about half the size of ancient Beijing. Once, about twenty million inhabitants had lived here, but after the completion of newer cities, the population had decreased to about nine million, so that it was no longer so crowded.…
Cheng Xin saw another sun appear in the sky before her. Cao Bin explained that there were a total of three artificial suns in the space city, all of them floating along the central axis, each separated by about ten kilometers. These produced energy by nuclear fusion, and brightened and dimmed on a twenty-four-hour cycle.
Cheng Xin felt a series of jolts. The bus was already at a stop, and the tremors seemed to originate from deep within the ground. She felt a force pushing against her back, but the bus remained unmoving. Outside the window, she could see the shadows cast by the trees and buildings suddenly shift to a new angle as the artificial suns abruptly shifted positions. But soon, the suns moved back into place. Cheng Xin saw that none of the passengers seemed surprised by this.
“The space city was adjusting its position,” said Cao Bin.
The bus arrived at the last stop after about thirty minutes. After getting off the bus, she saw that the everyday scenes that had so intoxicated her disappeared. In front of her was an enormous wall whose immense size made her gasp. It was as though she was standing at the end of the world—and indeed, she was. This was the “northernmost” point in the city, a large circular disk eight kilometers in diameter. She couldn’t see the entire disk from where she stood, but she could tell that the ground rose up on both sides of her. The top of the disk—the other side of the city—was about as high as the peak of Mount Everest. Many radial spokes converged from the rim of the disk to the center, four kilometers above. Each spoke was an elevator shaft, and the center was the space city’s gateway.
Before entering the elevator, Cheng Xin cast a lingering glance back at this city that already seemed so familiar. From here, all three suns were visible in a row toward the other end of the city. It was dusk, and the suns dimmed, turning from a blinding orange-white to a gentle red, bathing the city in a warm golden glow. Cheng Xin saw a few girls in white school uniforms chatting and laughing on a lawn not too far away, their hair wafting in the breeze and drenched in the golden glow of the evening sun.
The interior of the elevator car was very spacious, like a large hall. The side facing the city was transparent, turning the car into an observation deck. Every seat was equipped with seat belts because, as the elevator rose, gravity quickly diminished. As they looked outside, the ground sank lower, while the “sky,” another ground, grew clearer. By the time the elevator reached the center of the circle, gravity had completely disappeared, as well as the sensation of “up” and “down” when looking outside. Since this was the axis around which the city spun, the ground surrounded them in every direction. Here, the view of the city was at its most magnificent.
The three suns had dimmed to the level of moonlight, and their colors shifted to silver. Viewed from here, the three suns—or moons—were stacked on top of each other. All the clouds were concentrated in the gravity-free zone, forming an axis of white mist extending through the center of the city to the other end. The “southern” end, forty-five kilometers away, could be seen clearly. Cao Bin told Cheng Xin that that was where the city’s thrusters were located. The lights of the city had just come on. In Cheng Xin’s eyes, a sea of lights surrounded her and extended into the distance. She seemed to be looking down a giant well whose wall was covered with a brilliant carpet.
Cheng Xin casually locked her gaze on a certain spot in the city, and found the arrangement of buildings there very similar to the residential district of her home back in the Common Era. She imagined a certain ordinary apartment building in that area and a certain window on the second floor: Through blue curtains, a gentle light seeped, and behind the curtain, her mom and dad waited for her.…
She could not hold back her tears.
Ever since awakening for the first time during the Deterrence Era, Cheng Xin had never been able to integrate into the new eras, always feeling like a stranger from another time. But she could never have imagined that she would once again feel at home more than half a century later, here behind Jupiter, more than eight hundred million kilometers from the Earth. It was as if everything that she had been familiar with from more than three centuries ago had been picked up by a pair of invisible hands, rolled up like a giant painting, and then placed here as a new world slowly spinning around her.
Cheng Xin and Cao Bin entered a weightless corridor. This was a tube in which people moved by pulling the
mselves along handholds on cables. The passengers riding up from all the elevators along the rim gathered here to exit the city, and the corridor was filled with streaming crowds. A row of information windows appeared around the circular wall of the corridor, and the animated images in the windows were mostly news and ads. But the windows were few in number and neatly arranged, unlike the chaotic profusion of information windows in the previous era.
Cheng Xin had long since noticed that the overwhelming hyperinformation age had apparently ended. Information appeared in this world in a restrained, directed manner. Was this the result of changes in the Bunker World’s political and economic systems?
* * *
Emerging from the corridor, Cheng Xin first noticed the stars spinning overhead. The spin was very rapid and made her dizzy. The view around her opened up dramatically. They were standing on a circular plaza with a diameter of eight kilometers “atop” the space city. This was the city’s spaceport, and many spacecraft were parked here. Most of the vessels were shaped not too differently from those Cheng Xin had seen over sixty years ago, though these were generally smaller. Many were about the size of ancient automobiles. Cheng Xin noticed that the flames at the nozzles of the spaceships as they took off were far dimmer than what she remembered from more than half a century ago. The glow was a dark blue and no longer so blinding. This probably meant that the miniature fusion engines were much more efficient.
Cheng Xin saw an eye-catching red-glowing circle all around the exit, with a radius of about a hundred meters. She quickly understood its meaning: The space city was spinning, and, outside the circle, the centrifugal force became very strong. Moving outside the warning circle meant a dramatic increase in centrifugal force, and vessels parked out there had to be anchored, while pedestrians needed to wear magnetic shoes lest they be thrown out.
It was very cold here. Only when a nearby vessel took off did the engine’s heat bring a brief feeling of warmth. Cheng Xin shuddered—not just from the cold, but because she realized that she was completely exposed to space! But the air around her and the air pressure were real, and she could feel cold breezes. It appeared that the technology to contain an atmosphere in a nonenclosed area had advanced even further, to the point where an atmosphere could be maintained in completely open space.
Cao Bin saw her shock and said, “Oh, right now we can only maintain an atmosphere about ten meters thick above ‘ground.’” He hadn’t been in this world for too long, either, but he was already jaded by the technology that seemed like magic to Cheng Xin. He wanted to show her far more impressive sights.
Against the background of the spinning stars, Cheng Xin saw the Bunker World.
From here, most of the space cities behind Jupiter could be seen. She saw twenty-two cities (including the one she stood on), and there were four more blocked by the city they stood on. All twenty-six cities (six more than planned) were hiding in the shadow of Jupiter. They were loosely lined up in four rows, and reminded Cheng Xin of the spaceships lined up behind the giant rock in space more than sixty years ago. To one side of Asia I was North America I and Oceania I, and to the other side was Asia III. Only about fifty kilometers separated Asia I from its neighbors on either side, and Cheng Xin could feel their immensity, like two planets. The next row of four cities was 150 kilometers away, and it was difficult to tell their size visually. The most distant space cities were about one thousand kilometers away, and looked like delicate toys from here.
Cheng Xin thought of the space cities as a school of tiny fish hovering in place behind a giant rock to avoid the torrents in the river.
North America I, closest to Asia I, was a pure sphere. It and the cylindrical Asia I represented the two extremes of space city design. Most of the other space cities were football-shaped, though the ratios of major to minor axes were different in each. A few other space cities took on unusual shapes: a wheel with spokes, a spindle, etc.
Behind the other three gas giants were three more space city clusters, consisting of a total of thirty-eight space cities. Twenty-six were behind Saturn, four behind Uranus, and eight more behind Neptune. Those space cities were in safer locations, though the environs were even more desolate.
One of the space cities in front suddenly emitted a blue light. It was as though a small blue sun appeared in space, casting long shadows of the people and spaceships on the plaza. Cao Bin told Cheng Xin that this was because the space city’s thrusters had been activated to adjust its position. The space cities revolved around the Sun in parallel with Jupiter, just outside its orbit. Jupiter’s gravity gradually pulled the cities closer, and the cities had to constantly adjust their positions with thrusters. This operation required a great deal of energy. Once, the suggestion had been floated to turn the cities into Jupiter’s satellites that would only shift into new orbits around the Sun after the issuance of a dark forest strike warning. But until the advance warning system had been further refined and proven to be reliable, no space city wanted to take the risk.
“Lucky you! Now you get to see a sight that happens only once every three days.” Cao Bin pointed into space. Cheng Xin saw a tiny white dot in the distance, gradually growing bigger. Soon, it was a white sphere as big as a Ping-Pong ball.
“Europa?”
“That’s right. We’re very close to its orbit right now. Watch your footing and don’t be scared.”
Cheng Xin tried to figure out what Cao meant. She had always thought of celestial bodies as moving slowly, almost imperceptibly—as they did in most Earth-based observations. But then she remembered that the space city was not a Jovian satellite but remained stationary relative to it. Europa, on the other hand, was a satellite that moved very fast. She remembered its speed was about fourteen kilometers per second. If the space city was very close to Europa’s orbit, then …
The white sphere expanded rapidly—so fast that it seemed unreal. Europa soon took up most of the sky, and turned from a Ping-Pong ball into a giant planet. The sensation of “up” and “down” switched in an instant, and Cheng Xin felt as if Asia I were falling toward that white world. Next, the three-thousand-kilometer-diameter moon swept overhead so that for an instant, it took up the entire sky. The space city was skimming over the icy oceans of Europa, and Cheng Xin could clearly see the crisscrossing lines in that frozen landscape, like lines in a giant palm print. The air, disturbed by the passage of Europa, whipped around her, and Cheng Xin felt an invisible force dragging her from left to right—if she weren’t wearing magnetic shoes, she was sure she’d be pulled off the ground. Whatever was nearby that hadn’t been secured to the ground flew up, and a few cables attached to spaceships also drifted into the air. A terrifying rumbling came from below her—it was the immense frame of the space city reacting to the rapidly shifting gravity field of Europa. It took only about three minutes for Europa to hurtle past Asia I, and then it was on the other side of the city and began to shrink rapidly. The eight space cities in the two front-most rows all activated their thrusters to adjust their positions after the disturbance caused by Europa. Eight fireballs lit up the sky.
“How … how close was that?” Cheng Xin asked in an unsteady voice.
“The closest approach, like you experienced just now, was a hundred and fifty kilometers, basically brushing right by us. We don’t really have a choice. Jupiter has thirteen moons, and it’s impossible for the space cities to avoid them all. Europa’s orbit is inclined only slightly from the equator, and so it’s very close to these cities here. It’s the main source of water for the Jovian cities, and we’ve built a lot of industry on it. But when the dark forest strike comes, all of it will have to be sacrificed. After the solar explosion, all of the Jovian moons’ orbits will shift dramatically. Maneuvering the space cities to avoid them at that time will be a very complicated operation.”
Cao Bin found the dinghy he had taken to come here. It was tiny, shaped and sized like an ancient automobile, capable of seating only two. Cheng Xin instinctively felt unsafe going
into space in such a tiny vehicle, even though she knew her fear wasn’t reasonable. Cao Bin told the AI to go to North America I, and the dinghy took off.
Cheng Xin saw the ground receding quickly, and the dinghy flew along at a tangent to the spinning city. Soon, the eight-kilometer-diameter plaza came into view, followed by the entirety of Asia I. Behind the cylinder was a vast expanse of dark yellow. Only when the edge of this yellow expanse appeared did Cheng Xin realize that she was looking at Jupiter. Here, in the shadow of the gas giant, everything was cold and dark, and the Sun seemed to not exist at all. Only the phosphorescence of the planet’s liquid helium and hydrogen, diffused through the thick atmosphere, formed patches of hazy light roving about like eyeballs behind the closed eyelids of a dreamer. The immensity of Jupiter astonished Cheng Xin. From here, she could only see a small portion of its rim, and the rim’s curvature was minuscule. The planet was a dark barrier that blocked out everything, and once again gave Cheng Xin the feeling of standing at a giant wall at the end of the world.
* * *
In the following three days, Cao Bin took Cheng Xin to visit four more space cities.
The first was North America I, the closest city to Asia I. The main advantage of its spherical construction was that a single artificial sun at the center was sufficient to illuminate the entire city, but the disadvantage of such a design was obvious as well: The gravity changed depending on one’s latitude. The equator had the most gravity, which decreased as you went up in latitude. The polar regions were weightless. Inhabitants in the different regions had to adjust to life under various gravity conditions.