But now, perhaps, the Halo Group could help her realize her dream.

Cheng Xin came to the headquarters of the Halo Group. This was her first time here. She had never participated in its operation because, subconsciously, she never thought of the enormous wealth as truly hers, or Yun Tianming's. They possessed that star, but the wealth generated by the star belonged to society.

The corporate headquarters occupied an entire giant tree. Interestingly, all the buildings on the tree were transparent. Moreover, as the refractive index in the construction material was close to that of the air, all internal structures were visible. One could see employees moving inside as well as countless information windows. The hanging buildings resembled transparent ant farms with colorful ants milling about inside.

Inside the large conference room at the tip of the tree, Cheng Xin got to meet most of the high-level executives of the Halo Group. They were all young, smart, and vivacious. Most of them had never met Cheng Xin before, and they did not disguise their awe and adoration.

After the meeting, when only Cheng Xin and AA remained in the large, empty room, they began to talk about the future of the company. The message from Yun Tianming and the deciphering progress remained secrets from the public. To protect Tianming, Fleet International and the UN planned to release the results gradually to the public and to make them appear as the fruits of research on Earth. Some deliberate false research results would also be mixed in to further conceal the real origin of the information.

Cheng Xin had gotten used to the transparent floor and no longer felt so acrophobic. A few large information windows drifted in the conference room, displaying live video feeds from a few of the Halo Group's construction projects in Earth orbit, one of which was the giant cross in geosynchronous orbit. After Tianming's reappearance, the public's hopes for a miracle gradually faded, and with the initiation of the Bunker Project, the religious fervor dimmed. The church stopped investing in the giant cross, and it was abandoned. Now it was in the process of being dismantled so that only a giant "1" remained -- a rather meaningful sight.

"I don't like 'black domain,'" said AA. "It would be more appropriate to call it 'black tomb,' a tomb we dig for ourselves."

Cheng Xin looked at the city below through the transparent floor. "I don't think of it that way. During the era I was from, the Earth was completely separated from the rest of the universe. Everyone lived on the surface, and very rarely did they glance up at the stars. People had lived that way for five thousand years, and you can't just say that wasn't a good life. Even now, the Solar System is basically separated from the rest of the universe. The only people who are in deep space are the thousand or so people on those two spaceships."

"But I feel that if we separate ourselves from the stars, dreams will die."

"Not at all. In ancient times there was happiness and joy as well, and they had no fewer dreams than we. Also, even inside a black domain, we would still see the stars, only… who knows what that would look like… Personally, I don't like 'black domain' either."

"I know you don't."

"I like lightspeed ships."

"You think I'm just a capitalist? Well, you're not wrong. I am, and so are the members of the board of directors. We want to maximize profits. But that doesn't conflict with lightspeed spaceships. Politically, the government will devote the most resources into the Bunker Project and the black domain, but lightspeed ships will be left to entrepreneurs… We should put our efforts into the Bunker Project, and then use some of the profits to research lightspeed ships."

"We all like lightspeed ships. The Halo Group should build lightspeed ships!"

"I thought you weren't going to agree," Cheng Xin said. "This requires heavy investment in basic research."

"All right. We should start a Halo Group Academy of Sciences, too, and recruit scientists. Many of them have dreamed about lightspeed spaceflight, but they can't find such opportunities in national or international projects --"

"Here's my thinking, AA: Curvature propulsion and the black domain probably share some fundamental theories. We can wait for the government and the World Academy of Sciences to complete that part of the research, then develop it toward curvature propulsion."

"A warning! An attack!" she shouted.

A new window came to the forefront showing AA's secretary. She stared at AA and Cheng Xin, her face full of terror and shock.

"Any specifics?" AA asked.

AA was interrupted by a sudden surge of new information windows. Windows of all sizes appeared in every direction like a colorful avalanche, quickly burying the few original information windows showing feeds from the Halo Group's projects. A "window avalanche" like this usually indicated the sudden occurrence of some important event, but the flood of information often caused people to be overwhelmed, unable to find out what actually happened. Such was the case with AA and Cheng Xin. They saw that most of the windows were filled with complex text and animated figures, and only those windows that showed pure images could be taken in at a glance. In one of the windows, Cheng Xin saw a few faces looking upwards, then the lens zoomed in until a frightened pair of eyes filled the frame, accompanied by a cacophony of screams…

"In what direction? How far?"

"They activated the first observation unit in the Solar System advance warning system and found a photoid right away!"

"Is this an official warning?" Cheng Xin asked calmly.

"I don't think so. But it's in all the media. I'm sure it's real! Let's get to the spaceport and run for our lives!" The secretary disappeared from the window.

Cheng Xin and AA passed through the dense congeries of information windows and arrived at the transparent wall of the conference room. They saw that panic had already seized the city below them. A massive increase in the number of flying cars outside resulted in chaos, and every vehicle tried to force itself through the jam at high speed. One of the cars struck a giant tree building and erupted into a fireball. Soon, fire and columns of smoke appeared in two other locations in the city…

"I don't know. I don't know anything. All I know --"

AA picked out a few information windows and perused them carefully. Cheng Xin, on the other hand, tried to get in touch with the members of the IDC. Most of their phones were busy, and Cheng Xin managed to talk to only two committee members. One of them, like AA and Cheng Xin, knew nothing. The other, a PDC official, told Cheng Xin that he could confirm that Observation Unit #1 in the Solar System advance warning system had noticed some significant anomaly, but he didn't know the specifics. He also confirmed that Fleet International and the UN had not issued a formal dark forest strike alarm, but he wasn't optimistic.

"There are two possibilities for why no alarm has been issued: One, nothing has happened. Two, the photoid is too close and an alarm would be useless."

"We should go to Halo," AA said.

"Is there enough time?"

Halo was a corporate spaceship that belonged to the Halo Group. Right now, it was parked at the company's geosynchronous base. If the alarm was real, their only hope now was to ride the ship to Jupiter and hide out behind the gas giant before the photoid struck. As Jupiter was in opposition, and therefore as close to the Earth as it could be, it would take twenty-five to thirty days for the ship to fly from the Earth to Jupiter, which was just under the upper end of the range of estimates for when the photoid would strike. But this estimate seemed highly unreliable: The advance warning system was still being constructed, and couldn't have given such an early alert.

AA was only able to obtain one piece of specific information from her reading: The photoid was coming along the ecliptic plane. There were conflicting reports concerning its exact direction and distance from the Sun, and estimates of when the photoid would strike the sun diverged wildly: Some claimed that the world had another month; others said only a few hours.

"Why are you bringing this?" Cheng Xin asked.

"We have to do something instead of waiting here to die!" AA said. She dragged Cheng Xin out of the conference room and onto the parking lot at the top of the tree. They ducked into a flying car, but AA seemed to remember something and got out again. A few minutes later, she returned with an oblong object that resembled a violin case. She opened the case, took out what was inside, and carried it with her into the car, leaving the case behind.

Cheng Xin looked at what was in AA's hand and recognized the implement: a rifle, though adapted to shoot laser bolts instead of bullets.

Every city had a spaceport to service various small space vessels -- rather like ancient airports.

"The spaceport is sure to be filled with people -- who knows what's going to happen?" AA tossed the rifle onto the backseat and started the flying car.

The flying car merged into a mighty aerial stream of traffic. All the countless cars in the stream, like a swarm of locusts, were headed for the spaceport. They cast a flowing shadow along the ground, as though the city's blood was seeping out.

On an information window inside the car, Cheng Xin saw a live video feed taken from near-Earth orbit. Countless rising white lines appeared against the tan background of the continent and extended upward. They grew more numerous, denser, as though the Earth was growing white hair. The fireballs at the ends of the white lines were like fireflies drifting into space. This was the greatest collective escape into space in human history.

Ahead, a dozen or so white lines rose into the blue sky, trails left by spaceships. They rose straight up and then turned east and disappeared in the depths of the firmament. New white lines continuously shot up from the ground and extended into air, each line headed by a fireball that was brighter even than the sun: the flame from the fusion drives of the ships.

Their car arrived above the spaceport. About a hundred spacecraft were arrayed below, and more were being moved out of the giant hangar in the distance. Space planes had long since fallen out of use, and modern shuttles all took off vertically. Unlike the oddly shaped spacecraft Cheng Xin had seen at the port in the space elevator terminal station, these shuttles all had streamlined profiles, with three or four tail fins. They were now erected helter-skelter in the parking lot of the spaceport, like a forest of steel.

A loud rumbling came from the launch area, strangely reminding Cheng Xin of the noise made by the Moskstraumen. The ground quaked and her legs felt numb. A great bright glow appeared in the launch area, and a shuttle rose into the air on a ball of flame, adding yet another column of smoke to the sky. A great billowing cloud of white fog flowed toward them, bringing with it a strange burning smell. The fog wasn't generated by the engine of the shuttle, but by the boiled water from the coolant pool below the launch pad. As the launch area and the ships disappeared in the sweltering, muggy steam, people became even more agitated and anxious.

AA had called ahead to the hangar to move one of the Halo Group's shuttles onto the lot. She quickly picked out the shuttle from the air and landed their car next to it.

Cheng Xin looked at the shuttles around her. They were of different sizes: The smaller ones were only about a few meters tall, looking like giant versions of artillery shells. It was hard to imagine that such tiny crafts could escape the Earth's gravity well. There were also larger vessels, some as big as ancient airliners. The Halo Group's shuttle was medium-small in size, about ten meters tall, covered with a reflective metallic surface reminiscent of the droplets. The shuttle was parked on a wheeled launch frame so that it could be dragged to the launch point at a moment's notice. They would ride this shuttle to reach Halo in orbit.

"Can we wait a bit?" Cheng Xin asked.

AA looked over at the children and understood what Cheng Xin wanted. "All right. Go. We have to wait for our turn to get to the launch pad. It will be a while."

The teacher saw Cheng Xin walking over, and came up and grabbed her. "This shuttle is yours, isn't it? Please, please save the children." Her bangs stuck to her forehead, and tears and condensed fog wetted her face. She stared at Cheng Xin intently, as if hoping to seize her with her gaze. The children came over as well, and looked expectantly at Cheng Xin. "They're here for space camp, and they were scheduled to go up in orbit. But after the alert was issued, they refused to take us and sent others up in our place."

AA and Cheng Xin climbed up a slender set of stairs to board the shuttle. As the fog dissipated, Cheng Xin saw a crowd of children gathered not too far away. They appeared to be elementary school students under the age of ten, dressed in their school uniforms. A young teacher stood with them. Her long hair was buffeted by gusts of wind and she looked around helplessly.

In principle, shuttles could take off from any flat part of the ground. However, to prevent ground damage from the ultrahigh-temperature plasma generated by the fusion drive, the shuttles used a launch pad. The launch pad was equipped with a coolant pool and diversion channels to safely redirect the plasma.

The teacher let go of AA and stared at her, even more terrified than before. "How am I supposed to pick? How…" She looked around, not daring to meet the eyes of the children. She looked to be in utter pain, as if the gazes of the children burned her.

"Let's bring them," Cheng Xin said to AA.

Cheng Xin's gaze did not waver. AA shook her head. "We can only bring three more."

AA looked at Cheng Xin for a few seconds. There are billions of people on the Earth. Do you think you can save them all?

The answer surprised Cheng Xin. The deep-sea acceleration fluid was only necessary for stellar spaceships. But she had always thought Halo was a planetary ship and wasn't capable of voyaging beyond the Solar System.

"Where's your ship?" AA asked as she walked over.

"It's gone. Please, please!"

"All right. Then bring three!" The teacher let go of Cheng Xin and grabbed on to AA, terrified of losing this one chance.

"But our shuttle's capacity is eighteen!"

"You pick three, then," said AA.

"Halo can only seat five under maximum acceleration because it's equipped with only five deep-sea-state capsules. Anyone not in a deep-sea state is going to be crushed into a meat pie."

"A thousand!"

AA shook her head. "Wrong."

"Fine. I'll pick," AA said. She turned to the children and smiled. "Everyone, listen up. I'm going to ask three questions. Whoever gives the right answers first gets to come with us." She ignored the stunned looks from the teacher and Cheng Xin, and held up a finger. "First question: Say we have a light which is off. After one minute, it blinks. Half a minute later, it blinks again. Fifteen seconds later, it blinks a third time. It keeps on going like this, blinking at intervals that are half of the immediately preceding interval. I want to know how many times it will have blinked by the two-minute mark."

"No. Think carefully."

"Come here," AA said, pointing at the little girl. When she walked over, AA guided her to stand behind herself. "Second question: Say we have a rope whose thickness is uneven. To burn it from one end to the other takes an hour. How do you use this rope to track the passage of fifteen minutes? Remember, the thickness is uneven!"

"A hundred!" one of the children blurted out.

After a long pause, a timid voice spoke up. The speaker was a gentle and quiet little girl and it was hard to hear her with all the noise. "An infinite number of times."

Cheng Xin followed them to the stairs for boarding the shuttle. She looked back. The remaining children and their teacher looked at her as if at a sun that would never rise again. Tears blurred the scene in front of her, and as she climbed up, she could still feel the gazes of despair behind her, like ten thousand arrows piercing her heart. She had felt like this before, during the last moments of her brief career as the Swordholder, and also in Australia when Sophon had announced the plan for exterminating the human race. It was a pain worse than death.

"Ten!" a girl shouted.

AA gave her a thumb up. "Well done. Come over." Then she nodded at Cheng Xin, took the three children, and headed for the shuttle.

This time, no child spoke up in a hurry, and they all fell into deep thought. Soon, a boy raised his hand. "Fold the rope end to end, and then burn it from both ends at the same time."

AA nodded. "Come over." She pulled the boy behind her to stand with the girl. "Third question: eighty-two, fifty, twenty-six. What's the next number?"

She couldn't see any control surfaces inside the shuttle, and only a few information windows drifted by. The shuttle's AI seemed to recognize AA. As soon as she entered, the windows gathered around her. They moved with her while she went around securing the children's and Cheng Xin's seat belts.

The cabin inside the shuttle was spacious; eighteen seats were arranged in two columns. Since the cabin was vertical, like a well, everyone had to climb a ladder to get to the seats. Cheng Xin experienced the same feeling she had when inside the spherical spacecraft she took to meet Tianming -- the shuttle seemed to be a shell only, and she couldn't see where there was space for the engine and the control systems. She thought back to the chemical rockets of the Common Era, each as big as a skyscraper, but the effective payload was only a tiny capsule near the top.

"Auntie, are they going to die on the surface?" the boy asked.

"Don't look at me like that. I gave them a chance. Competition is necessary for survival," AA whispered to Cheng Xin.

The wait shouldn't have mattered much to their survival. The flight to Jupiter would take a month. If the dark forest strike happened before they arrived, it really made no difference if they were on the ground or in space. However, the problem now was that any delay might cause them to not be able to take off at all.

Society had already descended into pandemonium. Driven by the instinct for survival, the more than ten million inhabitants of the city swarmed toward the spaceport. The shuttles, like passenger aircraft during ancient times, could only carry away a small number of people in a short period of time. Possessing a private space vessel was like owning a private airplane, an unattainable dream for most of the population. Even with the space elevator, no more than one percent of the population could reach near-Earth orbit within a week. Those who could finally make the voyage to Jupiter would be one-tenth of that one percent.

"Everyone is going to die. It's just a matter of when." AA sat down next to Cheng Xin. She didn't buckle her seat belt, but continued to examine the information windows. "Damn it. There are still twenty-nine launches ahead of us."

The spaceport had a total of eight launch pads. After each launch, the pad had to cool for ten minutes before the next use because the coolant pools needed to be replenished with fresh water.

The plasma emitted by the nuclear fusion drive was tens of times hotter than the emissions of ancient chemical rockets. When launched from a flat surface, the plasma would melt the crust instantaneously and spill out in every direction. No one could survive within a thirty-meter radius. The video feed in the window showed many black dots scattering from the fireball. One of the dots struck a nearby shuttle and left a black mark: a burnt-up body. Several other shuttles around the one that took off toppled, probably because their launch frames had been melted.

Cheng Xin minimized the information window and turned around to comfort the three children seated behind her. AA screamed. Cheng Xin turned around and saw a window that had been maximized to fill the entire cabin. In the window, a blinding fireball had appeared in the forest of shuttles.

There were no portholes on the shuttle, but a few information windows showed the scene outside. They saw dark masses flooding into the parking area. Crowds surrounded every vessel, screaming with their fists raised, hoping to squeeze onto one of them. At the same time, outside the spaceport, some flying cars that had landed took off again. The cars were all empty, and their owners piloted them by remote control in an attempt to stop any more space launches. More and more flying cars gathered in the air, forming a dark, hovering barrier above the launch pads. Very soon, no one would be able to leave.

Someone had begun to launch while surrounded by people in the parking lot!

AA watched the horrifying scene and bit her bottom lip. Then she waved the window away and began to type on another small window.

"We're taking off."

"What are you doing?" Cheng Xin asked.

The crowd quieted. They looked up and saw the shuttle that had probably killed dozens of people lifting off from the parking lot, rumbling, dragging its white trail until it was high in the air, then turning east. They seemed unable to believe their eyes. A few seconds later, yet another shuttle took off from the parking lot, even closer to them. The rumbling, flames, and waves of superheated air threw the stunned crowd into complete panic. Then a third, a fourth… the shuttles in the parking lot took off one after another. Amidst the fiery balls of flame, burnt remains of bodies flew through the air, turning the parking lot into a crematorium.

"No."

"Look." AA tossed another small window at Cheng Xin, which showed the few shuttles around them. A cooling loop was located just above the tail nozzle of each vehicle. The loops were used to dissipate the heat from the fusion reactors. Cheng Xin saw that the loops of all the surrounding shuttles had begun to glow with a dim red light, indicating that their reactors had been turned on in preparation for liftoff.

"We'd better launch before they do," said AA. If any of these shuttles took off, the plasma would probably melt the launch frames of the rest of the shuttles, causing them to topple onto the molten ground.

"No. Stop." Cheng Xin's voice was calm, but unwavering. She had experienced even worse catastrophes, and she would face this one with serenity.

"Because there are people around."

"Our values still hold, at least for now. I'm the president of the Halo Group. This shuttle belongs to the Halo Group, and you're the company's employee. I have the authority to make this decision."

"Why?" AA's voice was equally calm.

AA stared at Cheng Xin for a few moments, then she nodded and closed the control window. She also turned off all the other information windows, thus isolating the cabin from the mad, noisy world outside.

AA stopped typing and turned to face Cheng Xin. "Soon, you, me, the crowd, and the Earth itself will all turn into tiny fragments. Can you tell which ones are honorable and which ones despicable in that mess?"

"If we can't leave, they can't leave either. Fuck them."

AA said nothing. But then she jumped up, as if suddenly remembering something. She picked up the laser rifle from one of the empty seats and climbed down the ladder. "Keep your seat belts on. The shuttle might fall over any moment."

"Thank you," said Cheng Xin.

AA opened the cabin door, went out, and immediately closed the door and locked it to prevent anyone from trying to force their way in. Then she climbed down the stairs and began to shoot at the tail fin of the nearest shuttle. Smoke rose up from the tail fin, leaving behind a tiny hole about the size of a finger. That was enough. The self-monitoring system within the shuttle would discover the damage to the tail fin and the AI would refuse to initiate the launch sequence. This was a safety measure that couldn't be overridden by those inside. The cooling ring around the shuttle began to fade, indicating a reactor shutdown. AA turned around in a circle and shot a hole through the tail fins of each of the eight shuttles around them. As the crowd was in total panic, no one noticed what she was doing amidst the waves of heat and smoke and dust.

"What are you going to do?" Cheng Xin asked.

AA climbed back up the stairs and pushed Cheng Xin, who had poked her head out, back in. Then she followed and shut the door behind her. She began to vomit.

The door of one of the other shuttles opened, and an elegantly dressed woman climbed down. She walked around the tail of the shuttle and soon discovered the hole. She began to cry hysterically, then rolled around on the ground. She tried to head-butt the launch frame, but no one paid any attention to her. All the crowd cared about was the door to her shuttle, which had been left open. They surged up the stairs and tried to squeeze into the shuttle that could no longer fly.

"It smells like… barbeque out there," AA finally said after the heaves subsided.

"We're going to witness a magnificent sight of the cosmos," AA said, a mysterious expression on her face. "What sight?"

"Are we going to die?" asked one of the girls, poking her head into the aisle from the seat above them.

"It's the most impressive thing ever. The Sun is going to turn into a giant firework."

AA smiled back. It was a smile Cheng Xin was familiar with. In her eyes, AA had always seemed young, less worn down by the darkness of the world that Cheng Xin had experienced. She felt more mature in front of AA, but also powerless.

"Then… nothing. What can there be when there's nothing?" AA climbed up and patted the three children on their heads in turn. She wasn't going to lie to them. If they could answer her questions, surely they were smart enough to understand the situation.

"Don't worry about it. It's all just busywork anyway. In the end, the result is going to be the same. At least now we can relax." AA exhaled.

"And then?"

AA seemed to sense what Cheng Xin was thinking. "Even if the advance warning system had been completely operational, we'd get at most a day's warning… But now that I've thought about it some, I think it's likely a false alarm."

Again, AA and Cheng Xin sat down next to each other. Cheng Xin put a hand over AA's hand. "I'm sorry."

If Halo really were a stellar ship, then it would be able to get to Jupiter much faster than she had expected. Although the distance between the Earth and Jupiter wasn't long enough for it to reach maximum acceleration, the whole journey should take only about two weeks.

Cheng Xin wasn't sure if that was why AA had submitted to her authority earlier so easily.

Once the outside had calmed down a bit, Cheng Xin and AA exited the shuttle. The scene that greeted them was like a battlefield. Burnt bodies lay everywhere, charcoal-black, a few still on fire. Many of the shuttles lay on the ground while others leaned against each other. In total, nine shuttles had taken off from the parking lot, and their trails were still clearly visible in the sky, like sliced-open wounds. The crowd was no longer frantic. Some sat on the still-hot ground, some stood in place, stunned, some wandered around aimlessly -- and everyone seemed uncertain whether they were experiencing reality or a nightmare. The police had arrived to maintain order, and rescue operations were underway.

AA's theory was quickly proven. The PDC official who was also a member of the IDC called Cheng Xin to let her know that Fleet International and the UN had issued a joint statement that the alarm was false. No signs of a dark forest strike had been detected. AA opened a few information windows, and most of them were broadcasting the announcement from Fleet International and the UN. Outside, the unauthorized launches had ceased. It was still chaotic, but at least the situation wouldn't deteriorate further.

The difference between a planetary spaceship and a stellar spaceship was like the difference between a ferryboat with a single oar plying a river and an oceangoing container ship with a tonnage measured in tens of thousands. Of course, in spaceships, the difference wasn't merely a matter of volume -- there were small stellar spaceships, too. Compared to planetary ships, stellar ships had more advanced propulsion systems, were equipped with ecological cycling systems, and every subsystem had three or four backups. If Cheng Xin really rode the new Halo into the shadow of Jupiter, the ship would be able to maintain her for the rest of her life, no matter what happened.

"The next warning may be real," AA said to Cheng Xin. "You should come with me to the back of Jupiter. The Halo Group will build a space city for the Bunker Project."

"We're not talking about the original ship with that name, but a new miniature stellar spaceship. It can seat twenty during planetary voyages, and five for stellar flight. The board of directors agreed to build it for you, and you can use it as a mobile office at Jupiter."

Instead of answering her, Cheng Xin asked, "What is going on with Halo?"

"You just don't want to be one of the few to survive."

"I'm here with billions of people. No matter what happens, if it happens to several billion at the same time, it won't be frightening."

"I've been through that already."

Cheng Xin shook her head. "You should go. Take Halo. I don't participate in the day-to-day operations of the company, and it's fine for me to stay on the Earth."

"I'm worried about you," AA said, and grabbed Cheng Xin by both shoulders. "I'm not worried that you'll die along with a few billion others, but that you'll experience things worse than death."

"If you continue to pursue the dream of lightspeed spaceflight, you'll encounter more such experiences. Can you really endure them?"

Most of the thousands of spaceports across the world had shuttles that took off while surrounded by crowds, and more than ten thousand people died in the flames of fusion drives. Armed conflicts also took place at the base stations of space elevators. Unlike at the spaceports, the fights at the space elevators involved nations. Some countries attempted to occupy the international elevator's base station in tropical waters, and only the timely confirmation that the attack alarm was false prevented full-scale warfare. In orbits around Earth, and even on Mars, groups of people fought over spaceships.

The false alarm was the largest social disturbance since the Great Resettlement. Although brief in duration and limited in the damage caused, it left an indelible mark in the psyche of the world.

In addition to the degenerates who were willing to kill to ensure their own survival, the public discovered something else that disgusted them during the course of the false alarm: tens of small stellar spaceships and near-stellar spaceships were discovered to be in secret construction in geosynchronous orbit and on the dark side of the moon. Near-stellar spaceships possessed the ecological cycling systems of stellar ships, but were only equipped with propulsion systems for interplanetary flight. Some of these luxurious yachts belonged to large companies, and others to extremely wealthy individuals. All the crafts were small, and could only maintain a few people with their ecological cycling systems. They had only one purpose: long-term seclusion behind the giant planets.

The advance warning system that was still being constructed could only provide a warning window of about twenty-four hours. If a dark forest strike really arrived, there wasn't enough time for any spacecraft to go from the Earth to Jupiter, the nearest barrier planet. In actuality, the Earth dangled over a sea of death. Rationally, everyone understood this, and the ugly fights that broke out during the false alarm were nothing more than meaningless mass madness driven by a survival instinct that overwhelmed rational thinking. Currently, about fifty thousand individuals resided at Jupiter -- most of them were space force personnel at the Jupiter base, along with some staff doing preparatory work for the Bunker Project. They had plenty of justification for being at Jupiter, and the public did not begrudge them their place. But once these secret stellar ships were completed, their wealthy owners would be able to hide in the shadow of Jupiter indefinitely.

Legally -- at least right now -- there was no international or national prohibition against the construction of stellar ships by organizations or individuals, and hiding out behind the gas giants wasn't the same as Escapism. However, the inequality here was seen as the greatest in human history: inequality before death.

Historically, inequality mainly manifested itself in areas like economics or social status, but death basically treated everyone the same. To be sure, such equality wasn't absolute: For instance, access to medical care wasn't evenly distributed; the wealthy fared better in natural disasters than the poor; soldiers and civilians had different rates of survival in war; and so on. But never before had a situation like this presented itself: less than one-ten-thousandth of the population could go into safe hiding, leaving billions on Earth to die.

Even in ancient times, such manifest inequality would have been intolerable, let alone now.

This led directly to international skepticism about the plan for lightspeed ships.

Although spaceships hiding permanently behind Jupiter or Saturn could survive a dark forest strike, life on those ships would not be enviable. No matter how comfortable the ecological cycling systems made the shipboard environment, the occupants would be living in the cold, desolate regions of the outer Solar System in isolation. But as observations of the Second Trisolaran Fleet revealed, spacecraft powered by curvature propulsion could achieve lightspeed almost instantaneously. A lightspeed ship could go from the Earth to Jupiter in less than an hour, and the advance warning system would be more than sufficient. Powerful and wealthy individuals who possessed lightspeed ships could thus live in comfort on the Earth and then escape at the last minute, without regard for the billions left behind. This was a prospect society simply could not tolerate. The terrifying sights from the false alarm remained fresh in the public's mind, and most people agreed that the appearance of lightspeed ships would lead to worldwide chaos. Thus, the plan for developing lightspeed ships faced unprecedented resistance.

[Excerpt from A Past Outside of Time, Space Sentries: The Solar System Advance Warning System]

The false alarm was the result of the explosive amplifying effects of a hyper-information society when fed sensitive news. Its source was an anomaly detected by the first observation unit of the advance warning system. The anomaly was real, though it had nothing to do with photoids.

The Earth had observed photoids only twice in the past: the destruction of 187J3X1 and of the Trisolaran system. Knowledge about the phenomenon was thus limited. All that was known was that a photoid moved at close to the speed of light, but there was no data concerning its volume, rest mass, or relativistic mass as it approached the speed of light. A photoid was certainly the most primitive weapon capable of attacking a star, since it relied only on the enormous kinetic energy generated by its high relativistic mass to damage the target. Once a civilization possessed the technology to accelerate an object to near the speed of light, a "bullet" with very little mass possessed immense destructive power. This was indeed "economical."

At first blush, it seemed impossible to give advance warning for photoids, because they moved at close to the speed of light. This meant that they moved almost as fast as the radiation they generated, and reached their target almost simultaneously. In other words, the observer was outside the event's light cone. But reality was a bit more complicated. Any object with rest mass could not achieve lightspeed. Although a photoid's speed approached lightspeed, it was still slightly slower than true lightspeed. This difference meant that the radiation from the photoid moved just a bit faster than the photoid itself. If the photoid had to travel a long distance, this difference was magnified. Also, a photoid's trajectory to the target wasn't an absolute straight line. Since it wasn't massless, it couldn't avoid the gravitational attractions of nearby celestial bodies, and its path typically ended up being slightly curved. The curvature was much greater than the curvature of light through the same gravitational field. For the photoid to strike the target, its trajectory had to take this effect into account. This meant that the path traveled by the photoid was longer than the path taken by its radiation.

The most valuable data concerning photoids was obtained right before the annihilation of the Trisolaran system. Scientists were able to make an important discovery: Due to a photoid's ultrahigh velocity, powerful radiation ranging from visible light to gamma rays was emitted as it collided with the few atoms scattered in space and interstellar dust. The radiation had distinctive characteristics. Since the photoids were extremely small, direct observation of them was impossible. But the characteristic radiation could be detected.

For these two reasons, the radiation from the photoid would reach the Solar System before the photoid itself. The twenty-four-hour estimated warning period was calculated based on the maximum distance at which photoid emissions could be observed. By the time the radiation reached the Earth, the photoid itself would still be about 180 AU away.

But that was merely the ideal scenario. If the photoid were launched from a nearby spaceship, there would be almost no warning -- like what had happened to Trisolaris.

Thirty-five observation units were planned for the Solar System advance warning system. These would monitor the sky in every direction for photoid emissions.

Observation Unit #1 was in fact just the Ringier-Fitzroy Station from the end of the Crisis Era. More than seventy years ago, it was this observation station that had first discovered the strong-interaction space probes -- the droplets. The station was still located on the outer edge of the asteroid belt, but all its equipment had been updated. Take the visible light telescope, for instance: The lenses were even bigger, and the first lens's diameter had increased from twelve hundred meters to two thousand meters, big enough for a small town to fit on it. These gigantic lenses were made from materials taken directly from the asteroid belt. The first one was a medium-sized lens five hundred meters in diameter. After that was finished, it was used to focus sunlight on asteroids so that the melted rock could be made into pure glass and then formed into additional lenses. In total, six lenses floated in a ten-kilometer-long column in space, far apart from each other. The observation station itself was located at the end of the column of lenses, and could only hold a crew of two.

[Broadcast Era, Year 8, Fate's Choice]

Two days before the false alarm; Observation Unit #1

The crew was still made up of a scientist and a military officer. The officer was responsible for monitoring photoid emissions, while the scientist conducted astronomical and cosmological research. Thus, the tradition of fighting for observation time begun three centuries ago by General Fitzroy and Dr. Ringier continued.

After this, the largest telescope in history, had completed its shakedown tests and successfully taken its first image -- a star forty-seven light-years away -- Widnall, the astronomer on the crew, was as excited as if he'd just had a son. Laymen did not understand that previous telescopes could only amplify the luminosity of stars outside the Solar System, not reveal any shapes. No matter how powerful the telescopes were, the stars always showed up as tiny point sources, only incrementally brighter than images taken by lesser telescopes. But now, in the view of this ultrapowerful telescope, a star showed up as a disk for the first time. Though it was small, like a Ping-Pong ball seen from tens of meters away, and one couldn't see any details in the disk, this was still an epochal moment in the history of the ancient science of visible-light astronomy.

Widnall's eyes temporarily left the terminal showing the image from the telescope and looked out the porthole of the station. He could see a few irregularly shaped rocks drifting at some distance: fragments of asteroids left from the glass-making operation. They spun slowly in the cold sunlight and seemed to emphasize the desolation of space. The scene did seem to evoke a sense of the "mental space" the sublieutenant described.

But Sublieutenant Vasilenko wasn't impressed. "I think you need to remember our role here: We are sentries. In the old days, we'd be perched atop a wooden watchtower on the frontier, a desolate desert or snowfield around us. Standing erect in the frigid breeze, we'd be gazing in the direction of the enemy. As soon as we saw tanks coming up the horizon, or men on horses, we'd make a call or light smoke signals to inform the homeland that the enemy invasion had begun… You need to get into that mental space. Don't think of yourself as being in an observatory."

"The cataracts have been removed from the eyes of astronomy!" said Widnall dramatically, wiping his eyes.

The observation station received new orders from Fleet Command to adjust the telescope and observe the remnants of the Trisolaran system. Widnall didn't argue with Vasilenko this time, because he was very interested in that ruined world as well.

Widnall said, "If we really discover a photoid, it would be better to not issue a warning at all. It's useless, anyway. To die suddenly without even knowing what hit you is actually a rather fortunate fate. But you'd rather torture a few billion people for twenty-four hours. I think that's akin to a crime against humanity."

"By that logic, you and I would be the most unfortunate people in the world since we would know about our fate the longest."

The floating lenses began to move around and adjust their positions, the plasma thrusters at the rims of the lenses emitting blue flames. Only now did the lenses in the distance reveal themselves, the blue flames marking out the overall shape of the telescope. The ten-kilometer-long group of lenses slowly turned, stopping when the telescope was pointed in the direction of the Trisolaran system. Then the lenses shifted up and down the axis to focus. Finally, most of the flames went out, with only a few fireflies flickering now and then as the lenses engaged in precision focus adjustments.

In the unprocessed view of the telescope, the Trisolaran system looked very ordinary, just a small patch of white against the background of space, like a feather. But after the image had been processed and magnified, it appeared as a magnificent nebula that took up the entire screen. It had been seven years since the explosion of the star, so what they were seeing now was the scene three years after the explosion. Under the influence of gravity and the exploded star's angular momentum, the nebula had turned from sharp radiating rays into a soft blur of clouds, which was then flattened by the centrifugal force of the spin into a spiral. Above the nebula, the two remaining stars could be seen. One of them showed up as a disk, while the other one, more distant, remained a point of light distinguished only by its motion against the background stars.

The two stars that survived the catastrophe achieved the dream of generations on Trisolaris and formed a stable double-star system, but no life would enjoy their light, as the entire system was now uninhabitable. It was now apparent that the dark forest strike had destroyed only one star out of the three, not only because of economics, but also to achieve a more sinister goal: As long as the system still retained one or two stars, the material in the nebula would be constantly absorbed by the stars, generating powerful radiation in the process. The Trisolaran system was now a radiation furnace, a domain of death for life and civilization. It was the powerful radiation that caused the nebula itself to glow and appear so clear and bright on the telescope.

Widnall examined the image some more and made an important discovery. "What is that?!" He pointed at a spot in the image some distance from the nebula. By scale, it was about thirty AU from the nebula center.

Seeing this silvery graveyard more than forty trillion kilometers away made Widnall wax philosophical. "From a scientific perspective, 'destroy' isn't really accurate. Nothing has disappeared. All the matter that used to be there is still there, and so is all the angular momentum. It's only the arrangement of matter that has changed, like a deck of cards being reshuffled. But life is like a straight flush: Once you shuffle, it's gone."

Vasilenko stared at the spot. He lacked the trained eye of an astronomer, and couldn't see anything unusual at first. But eventually, he saw a vague circular outline against the pitch-black background, like a soap bubble in space.

"I'm reminded of the clouds viewed from atop Mount Emei," said Vasilenko. "That's a mountain in China. Viewing the moon from the peak is an exquisite sight. The night I was there, the peak floated in a boundless sea of clouds, turned pure silver by the moon above. It looked a lot like this."

"Absolutely not. Dust doesn't look anything like that."

"No one could have seen it. Whatever it is, it's transparent, with a very faint border. The largest telescopes in the past wouldn't have been able to detect it."

"It's very large. The diameter is about… ten astronomical units. Is it dust?"

Widnall zoomed out a bit to get a better sense of the position of the strange new object with respect to the double stars, and to try to observe the spin of the nebula. On the screen, the nebula again turned into a small patch of white against the black abyss of space.

About six thousand AU from the Trisolaran system, he found another "soap bubble." This one was much bigger than the first, with a diameter of about fifty AU, spacious enough to contain the Trisolaran system or the Solar System.

"You've never seen it before?"

Widnall stared at the screen for a while and said, tentatively, "That's where the Second Trisolaran Fleet went into lightspeed, isn't it?"

"My God!" Vasilenko cried out. "Do you know where that is?"

"Exactly."

"You're certain?"

"My old job was to observe this part of space. I know it better than the palm of my hand."

The conclusion was inescapable: Ships using curvature propulsion left behind trails as they accelerated to lightspeed. The trails apparently did not fade with time, but expanded and altered the nature of the space around them.

The first, smaller bubble was inside the Trisolaran system. There were several possible explanations for its existence. Perhaps the Trisolarans did not know initially that curvature propulsion would leave behind such trails, and the bubble was an accident created during engine tests or test flights; or perhaps they did know about the trails, but left them within the star system by mistake. But it was certain that they wanted to avoid purposefully leaving such trails. Eleven years ago, the Second Trisolaran Fleet had cruised for a full year using conventional means, and only when they were six thousand AU from their home world did they engage the curvature engines to enter lightspeed. The purpose was to start the trails as far from the home world as possible, though by that time it was already too late.

"That's a bit of a stretch. We've just begun researching lightspeed ships. It would be impressive if we managed to build one in half a century."

"This is an alarm! We have to tell people not to expose us."

At the time, the behavior of the Second Trisolaran Fleet had puzzled people. The most convincing explanation was that they were trying to avoid ill effects on the home world caused by 415 ships entering lightspeed. However, it was clear now that they were trying to avoid exposing the location of Trisolaris by the trails of curvature propulsion. The Second Trisolaran Fleet had exited lightspeed when it was still six thousand AU from the Solar System for the same reason.

"We have to report this right away," said Widnall. "But it's not time yet for our scheduled report. A report now would be treated as an alarm."

Widnall and Vasilenko stared at each other, and they could each see the terror building in the other's eyes. They had reached the same conclusion.

"But what if an initial test generates such a trail? Maybe they're already conducting such trials somewhere in the Solar System!"

The curvature trails were left behind when ships entered lightspeed, just as a rocket launching from the ground left burn marks on the launch pad. Once the ship was at lightspeed, it continued to coast by inertia, and left no more trails. It was a reasonable conjecture that dropping out of lightspeed would leave behind similar marks. It was still unknown how long such trails would persist in space. A guess was that the trails represented some kind of distortion in space due to curvature propulsion, and might last a long time -- maybe even forever.

It was reasonable to conclude that Sophon had claimed Trisolaris appeared more dangerous than the Solar System when observed from a distance because of the ten-AU-diameter curvature propulsion trail left behind within the Trisolaran system, which is what caused the dark forest strike against Trisolaris to come so quickly. The trail and the broadcast of Trisolaris's location mutually provided confirmation and made the danger value of the Trisolaran system skyrocket.

And so this information was transmitted to Fleet Command with an alarm-level neutrino beam, then passed on to the PDC. There, it was leaked and mistaken as a photoid attack alarm, which caused the global panic two days later.

During the following month, Observation Unit #1 discovered six more curvature propulsion trails in different parts of space. All of these were approximately spherical, though their sizes varied widely, ranging from fifteen to two hundred AU. One of these bubbles was only six thousand AU from the Solar System, apparently the mark left by the Second Trisolaran Fleet as it dropped out of lightspeed. The directions and distances of the other trails, however, seemed to indicate that they had nothing to do with the Second Trisolaran Fleet. It appeared that curvature propulsion trails were common in the universe.

One of the trails was only 1.4 light-years from the Sun, close to the Oort Cloud. A spaceship had apparently lingered there and then left by entering lightspeed. No one knew when this had happened.

The discovery of the curvature propulsion trail finally eliminated lightspeed space flight, already facing mounting skepticism, from consideration as a viable plan. Fleet International and the UN quickly enacted legislation prohibiting any further research and development of curvature propulsion, and the nation states followed suit. This was the most severe legal restriction against a technology since the nuclear nonproliferation treaties of three centuries ago.

After Blue Space and Gravity's discovery inside the four-dimensional space fragment, this provided yet more direct evidence that large numbers of highly intelligent civilizations existed in the cosmos.

Superficially, research and development of lightspeed spaceflight died for obvious reasons: to avoid advance exposure of the existence of Earth civilization by the trails generated from curvature propulsion, and to prevent increasing the Solar System's danger value in the eyes of observers elsewhere in the cosmos, either of which might have led to an earlier dark forest strike. But there were deeper reasons, too.

Humanity now had only two choices left: the Bunker Project and the Black Domain Plan.

Excerpt from A Past Outside of Time, Terror of the Endless Night

From the Common Era to the end of the Crisis Era, humanity looked at the stars with hope. But the first few steps they took toward the stars resulted in failure and pain. The tragic Doomsday Battle revealed the extent of humanity's fragility in the cosmos, and the internecine warfare of the Battle of Darkness had injured the human spirit in equal measure. Later events, such as the judgment of Bronze Age and the hijacking of Gravity by Blue Space, resulting in the universal broadcast, all deepened these wounds and elevated the pain to the level of philosophy.

On the other hand, both staunch opponents and fervent supporters of lightspeed spaceships belonged to the elite classes of society.

They cared far more about the Bunker Project, which seemed the most practical path to survival. To be sure, they also cared for the Black Domain Plan, because three centuries of horror had infused them with a strong desire for a serene life, and the Black Domain Plan promised just such a life. Although people were disappointed at the prospect of being sealed off from the rest of the universe, the Solar System itself was large enough that the disappointment was tolerable. The reason they were more interested in the Bunker Project than the Black Domain Plan was because even laypeople could see the extreme technical challenges of slowing down lightspeed, and generally agreed that it was unlikely for mere Man to complete God's Engineering Project.

As a matter of fact, most of the general public was relatively uninvested in the quest for lightspeed spaceships. They believed that even if such ships could be built within their lifetimes, they would have no chance of making use of them.

The faction in support of researching lightspeed spaceflight believed that the ultimate security of the human race required expansion into the Milky Way and settlement among the stars. In this unfeeling cosmos, only outward-facing civilizations had a chance of survival, and isolationism ultimately led to annihilation. Those who held such views generally did not oppose the Bunker Project, but passionately despised the Black Domain Plan, viewing it as an attempt to dig humankind's own grave. Even though they conceded that a black domain would guarantee the long-term survival of the human race, they saw such life as death for the civilization.

The faction opposed to researching lightspeed vessels felt this way for political reasons. They believed that human civilization had suffered many trials before reaching a nearly ideal democratic society, but once humanity headed for space, it would inevitably regress socially. Space was like a distorting mirror that magnified the dark side of humanity to the maximum. A line from one of the Bronze Age defendants, Sebastian Schneider, became their slogan: When humans are lost in space, it takes only five minutes to reach totalitarianism.

The child that was human civilization had opened the door to her home and glanced outside. The endless night terrified her so much that she shuddered against the expansive and profound darkness, and shut the door firmly.

For a democratic, civilized Earth to scatter innumerable seeds of totalitarianism among the Milky Way was a prospect that these people found intolerable.