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Last January, the Chinese Academy of Sciences invited Liu Cixin, China’s preeminent science-fiction writer, to visit its new state-of-the-art radio dish in the country’s southwest. Almost twice as wide as the dish at America’s Arecibo Observatory, in the Puerto Rican jungle, the new Chinese dish is the largest in the world, if not the universe. Though it is sensitive enough to detect spy satellites even when they’re not broadcasting, its main uses will be scientific, including an unusual one: The dish is Earth’s first flagship observatory custom-built to listen for a message from an extraterrestrial intelligence. If such a sign comes down from the heavens during the next decade, China may well hear it first. To hear more feature stories, see our full list or get the Audm iPhone app. In some ways, it’s no surprise that Liu was invited to see the dish. He has an outsize voice on cosmic affairs in China, and the government’s aerospace agency sometimes asks him to consult on science missions. Liu is the patriarch of the country’s science-fiction scene. Other Chinese writers I met attached the honorific Da, meaning “Big,” to his surname. In years past, the academy’s engineers sent Liu illustrated updates on the dish’s construction, along with notes saying how he’d inspired their work.

But in other ways Liu is a strange choice to visit the dish. He has written a great deal about the risks of first contact. He has warned that the “appearance of this Other” might be imminent, and that it might result in our extinction. “Perhaps in ten thousand years, the starry sky that humankind gazes upon will remain empty and silent,” he writes in the postscript to one of his books. “But perhaps tomorrow we’ll wake up and find an alien spaceship the size of the Moon parked in orbit.”

In recent years, Liu has joined the ranks of the global literati. In 2015, his novel The Three-Body Problem became the first work in translation to win the Hugo Award, science fiction’s most prestigious prize. Barack Obama told The New York Times that the book—the first in a trilogy—gave him cosmic perspective during the frenzy of his presidency. Liu told me that Obama’s staff asked him for an advance copy of the third volume. At the end of the second volume, one of the main characters lays out the trilogy’s animating philosophy. No civilization should ever announce its presence to the cosmos, he says. Any other civilization that learns of its existence will perceive it as a threat to expand—as all civilizations do, eliminating their competitors until they encounter one with superior technology and are themselves eliminated. This grim cosmic outlook is called “dark-forest theory,” because it conceives of every civilization in the universe as a hunter hiding in a moonless woodland, listening for the first rustlings of a rival.

Liu’s trilogy begins in the late 1960s, during Mao’s Cultural Revolution, when a young Chinese woman sends a message to a nearby star system. The civilization that receives it embarks on a centuries-long mission to invade Earth, but she doesn’t care; the Red Guard’s grisly excesses have convinced her that humans no longer deserve to survive. En route to our planet, the extraterrestrial civilization disrupts our particle accelerators to prevent us from making advancements in the physics of warfare, such as the one that brought the atomic bomb into being less than a century after the invention of the repeating rifle. Science fiction is sometimes described as a literature of the future, but historical allegory is one of its dominant modes. Isaac Asimov based his Foundation series on classical Rome, and Frank Herbert’s Dune borrows plot points from the past of the Bedouin Arabs. Liu is reluctant to make connections between his books and the real world, but he did tell me that his work is influenced by the history of Earth’s civilizations, “especially the encounters between more technologically advanced civilizations and the original settlers of a place.” One such encounter occurred during the 19th century, when the “Middle Kingdom” of China, around which all of Asia had once revolved, looked out to sea and saw the ships of Europe’s seafaring empires, whose ensuing invasion triggered a loss in status for China comparable to the fall of Rome. “It looks like something out of science fiction,” Liu said. This past summer, I traveled to China to visit its new observatory, but first I met up with Liu in Beijing. By way of small talk, I asked him about the film adaptation of The Three-Body Problem. “People here want it to be China’s Star Wars,” he said, looking pained. The pricey shoot ended in mid-2015, but the film is still in postproduction. At one point, the entire special-effects team was replaced. “When it comes to making science-fiction movies, our system is not mature,” Liu said.

I had come to interview Liu in his capacity as China’s foremost philosopher of first contact, but I also wanted to know what to expect when I visited the new dish. After a translator relayed my question, Liu stopped smoking and smiled. “It looks like something out of science fiction,” he said. A week later, I rode a bullet train out of Shanghai, leaving behind its purple Blade Runner glow, its hip cafés and craft-beer bars. Rocketing along an elevated track, I watched high-rises blur by, each a tiny honeycomb piece of the rail-linked urban megastructure that has recently erupted out of China’s landscape. China poured more concrete from 2011 to 2013 than America did during the entire 20th century. The country has already built rail lines in Africa, and it hopes to fire bullet trains into Europe and North America, the latter by way of a tunnel under the Bering Sea. The skyscrapers and cranes dwindled as the train moved farther inland. Out in the emerald rice fields, among the low-hanging mists, it was easy to imagine ancient China—the China whose written language was adopted across much of Asia; the China that introduced metal coins, paper money, and gunpowder into human life; the China that built the river-taming system that still irrigates the country’s terraced hills. Those hills grew steeper as we went west, stair-stepping higher and higher, until I had to lean up against the window to see their peaks. Every so often, a Hans Zimmer bass note would sound, and the glass pane would fill up with the smooth, spaceship-white side of another train, whooshing by in the opposite direction at almost 200 miles an hour.

It was mid-afternoon when we glided into a sparkling, cavernous terminal in Guiyang, the capital of Guizhou, one of China’s poorest, most remote provinces. A government-imposed social transformation appeared to be under way. Signs implored people not to spit indoors. Loudspeakers nagged passengers to “keep an atmosphere of good manners.” When an older man cut in the cab line, a security guard dressed him down in front of a crowd of hundreds.

The next morning, I went down to my hotel lobby to meet the driver I’d hired to take me to the observatory. Two hours into what was supposed to be a four-hour drive, he pulled over in the rain and waded 30 yards into a field where an older woman was harvesting rice, to ask for directions to a radio observatory more than 100 miles away. After much frustrated gesturing by both parties, she pointed the way with her scythe. We set off again, making our way through a string of small villages, beep-beeping motorbike riders and pedestrians out of our way. Some of the buildings along the road were centuries old, with upturned eaves; others were freshly built, their residents having been relocated by the state to clear ground for the new observatory. A group of the displaced villagers had complained about their new housing, attracting bad press—a rarity for a government project in China. Western reporters took notice. “China Telescope to Displace 9,000 Villagers in Hunt for Extraterrestrials,” read a headline in The New York Times. The search for extraterrestrial intelligence (seti) is often derided as a kind of religious mysticism, even within the scientific community. Nearly a quarter century ago, the United States Congress defunded America’s seti program with a budget amendment proposed by Senator Richard Bryan of Nevada, who said he hoped it would “be the end of Martian-hunting season at the taxpayer’s expense.” That’s one reason it is China, and not the United States, that has built the first world-class radio observatory with seti as a core scientific goal.

seti does share some traits with religion. It is motivated by deep human desires for connection and transcendence. It concerns itself with questions about human origins, about the raw creative power of nature, and about our future in this universe—and it does all this at a time when traditional religions have become unpersuasive to many. Why these aspects of seti should count against it is unclear. Nor is it clear why Congress should find seti unworthy of funding, given that the government has previously been happy to spend hundreds of millions of taxpayer dollars on ambitious searches for phenomena whose existence was still in question. The expensive, decades-long missions that found black holes and gravitational waves both commenced when their targets were mere speculative possibilities. That intelligent life can evolve on a planet is not a speculative possibility, as Darwin demonstrated. Indeed, seti might be the most intriguing scientific project suggested by Darwinism. Even without federal funding in the United States, seti is now in the midst of a global renaissance. Today’s telescopes have brought the distant stars nearer, and in their orbits we can see planets. The next generation of observatories is now clicking on, and with them we will zoom into these planets’ atmospheres. seti researchers have been preparing for this moment. In their exile, they have become philosophers of the future. They have tried to imagine what technologies an advanced civilization might use, and what imprints those technologies would make on the observable universe. They have figured out how to spot the chemical traces of artificial pollutants from afar. They know how to scan dense star fields for giant structures designed to shield planets from a supernova’s shock waves.

In 2015, the Russian billionaire Yuri Milner poured $100 million of his own cash into a new seti program led by scientists at UC Berkeley. The team performs more seti observations in a single day than took place during entire years just a decade ago. In 2016, Milner sank another $100 million into an interstellar-probe mission. A beam from a giant laser array, to be built in the Chilean high desert, will wallop dozens of wafer-thin probes more than four light-years to the Alpha Centauri system, to get a closer look at its planets. Milner told me the probes’ cameras might be able to make out individual continents. The Alpha Centauri team modeled the radiation that such a beam would send out into space, and noticed striking similarities to the mysterious “fast radio bursts” that Earth’s astronomers keep detecting, which suggests the possibility that they are caused by similar giant beams, powering similar probes elsewhere in the cosmos. Andrew Siemion, the leader of Milner’s seti team, is actively looking into this possibility. He visited the Chinese dish while it was still under construction, to lay the groundwork for joint observations and to help welcome the Chinese team into a growing network of radio observatories that will cooperate on seti research, including new facilities in Australia, New Zealand, and South Africa. When I joined Siemion for overnight seti observations at a radio observatory in West Virginia last fall, he gushed about the Chinese dish. He said it was the world’s most sensitive telescope in the part of the radio spectrum that is “classically considered to be the most probable place for an extraterrestrial transmitter.”

Before I left for China, Siemion warned me that the roads around the observatory were difficult to navigate, but he said I’d know I was close when my phone reception went wobbly. Radio transmissions are forbidden near the dish, lest scientists there mistake stray electromagnetic radiation for a signal from the deep. Supercomputers are still sifting through billions of false positives collected during previous seti observations, most caused by human technological interference. My driver was on the verge of turning back when my phone reception finally began to wane. The sky had darkened in the five hours since we’d left sunny Guiyang. High winds were whipping between the Avatar-style mountains, making the long bamboo stalks sway like giant green feathers. A downpour of fat droplets began splattering the windshield just as I lost service for good. Jon Juarez The week before, Liu and I had visited a stargazing site of a much older vintage. In 1442, after the Ming dynasty moved China’s capital to Beijing, the emperor broke ground on a new observatory near the Forbidden City. More than 40 feet high, the elegant, castlelike structure came to house China’s most precious astronomical instruments. No civilization on Earth has a longer continuous tradition of astronomy than China, whose earliest emperors drew their political legitimacy from the sky, in the form of a “mandate of heaven.” More than 3,500 years ago, China’s court astronomers pressed pictograms of cosmic events into tortoiseshells and ox bones. One of these “oracle bones” bears the earliest known record of a solar eclipse. It was likely interpreted as an omen of catastrophe, perhaps an ensuing invasion.

Liu and I sat at a black-marble table in the old observatory’s stone courtyard. Centuries-old pines towered overhead, blocking the hazy sunlight that poured down through Beijing’s yellow, polluted sky. Through a round, red portal at the courtyard’s edge, a staircase led up to a turretlike observation platform, where a line of ancient astronomical devices stood, including a giant celestial globe supported by slithering bronze dragons. The starry globe was stolen in 1900, after an eight-country alliance stormed Beijing to put down the Boxer Rebellion. Troops from Germany and France flooded into the courtyard where Liu and I were sitting, and made off with 10 of the observatory’s prized instruments. The instruments were eventually returned, but the sting of the incident lingered. Chinese schoolchildren are still taught to think of this general period as the “century of humiliation,” the nadir of China’s long fall from its Ming-dynasty peak. Back when the ancient observatory was built, China could rightly regard itself as the lone survivor of the great Bronze Age civilizations, a class that included the Babylonians, the Mycenaeans, and even the ancient Egyptians. Western poets came to regard the latter’s ruins as Ozymandian proof that nothing lasted. But China had lasted. Its emperors presided over the planet’s largest complex social organization. They commanded tribute payments from China’s neighbors, whose rulers sent envoys to Beijing to perform a baroque face-to-the-ground bowing ceremony for the emperors’ pleasure.

In the first volume of his landmark series, Science and Civilisation in China, published in 1954, the British Sinologist Joseph Needham asked why the scientific revolution hadn’t happened in China, given its sophisticated intellectual meritocracy, based on exams that measured citizens’ mastery of classical texts. This inquiry has since become known as the “Needham Question,” though Voltaire too had wondered why Chinese mathematics stalled out at geometry, and why it was the Jesuits who brought the gospel of Copernicus into China, and not the other way around. He blamed the Confucian emphasis on tradition. Other historians blamed China’s remarkably stable politics. A large landmass ruled by long dynasties may have encouraged less technical dynamism than did Europe, where more than 10 polities were crammed into a small area, triggering constant conflict. As we know from the Manhattan Project, the stakes of war have a way of sharpening the scientific mind. Still others have accused premodern China of insufficient curiosity about life beyond its borders. (Notably, there seems to have been very little speculation in China about extraterrestrial life before the modern era.) This lack of curiosity is said to explain why China pressed pause on naval innovation during the late Middle Ages, right at the dawn of Europe’s age of exploration, when the Western imperial powers were looking fondly back through the medieval fog to seafaring Athens.

Whatever the reason, China paid a dear price for slipping behind the West in science and technology. In 1793, King George III stocked a ship with the British empire’s most dazzling inventions and sent it to China, only to be rebuffed by its emperor, who said he had “no use” for England’s trinkets. Nearly half a century later, Britain returned to China, seeking buyers for India’s opium harvest. China’s emperor again declined, and instead cracked down on the local sale of the drug, culminating in the seizure and flamboyant seaside destruction of 2 million pounds of British-owned opium. Her Majesty’s Navy responded with the full force of its futuristic technology, running ironclad steamships straight up the Yangtze, sinking Chinese junk boats, until the emperor had no choice but to sign the first of the “unequal treaties” that ceded Hong Kong, along with five other ports, to British jurisdiction. After the French made a colony of Vietnam, they joined in this “slicing of the Chinese melon,” as it came to be called, along with the Germans, who occupied a significant portion of Shandong province. Meanwhile Japan, a “little brother” as far as China was concerned, responded to Western aggression by quickly modernizing its navy, such that in 1894, it was able to sink most of China’s fleet in a single battle, taking Taiwan as the spoils. And this was just a prelude to Japan’s brutal mid-20th-century invasion of China, part of a larger campaign of civilizational expansion that aimed to spread Japanese power to the entire Pacific, a campaign that was largely successful, until it encountered the United States and its city-leveling nukes.

China’s humiliations multiplied with America’s rise. After sending 200,000 laborers to the Western Front in support of the Allied war effort during World War I, Chinese diplomats arrived at Versailles expecting something of a restoration, or at least relief from the unequal treaties. Instead, China was seated at the kids’ table with Greece and Siam, while the Western powers carved up the globe. China has learned the hard way that spectacular scientific achievements confer prestige upon nations. Only recently has China regained its geopolitical might, after opening to the world during Deng Xiaoping’s 1980s reign. Deng evinced a near-religious reverence for science and technology, a sentiment that is undimmed in Chinese culture today. The country is on pace to outspend the United States on R&D this decade, but the quality of its research varies a great deal. According to one study, even at China’s most prestigious academic institutions, a third of scientific papers are faked or plagiarized. Knowing how poorly the country’s journals are regarded, Chinese universities are reportedly offering bonuses of up to six figures to researchers who publish in Western journals. It remains an open question whether Chinese science will ever catch up with that of the West without a bedrock political commitment to the free exchange of ideas. China’s persecution of dissident scientists began under Mao, whose ideologues branded Einstein’s theories “counterrevolutionary.” But it did not end with him. Even in the absence of overt persecution, the country’s “great firewall” handicaps Chinese scientists, who have difficulty accessing data published abroad.

China has learned the hard way that spectacular scientific achievements confer prestige upon nations. The “Celestial Kingdom” looked on from the sidelines as Russia flung the first satellite and human being into space, and then again when American astronauts spiked the Stars and Stripes into the lunar crust. China has largely focused on the applied sciences. It built the world’s fastest supercomputer, spent heavily on medical research, and planted a “great green wall” of forests in its northwest as a last-ditch effort to halt the Gobi Desert’s spread. Now China is bringing its immense resources to bear on the fundamental sciences. The country plans to build an atom smasher that will conjure thousands of “god particles” out of the ether, in the same time it took cern’s Large Hadron Collider to strain out a handful. It is also eyeing Mars. In the technopoetic idiom of the 21st century, nothing would symbolize China’s rise like a high-definition shot of a Chinese astronaut setting foot on the red planet. Nothing except, perhaps, first contact. At a security station 10 miles from the dish, I handed my cellphone to a guard. He locked it away in a secure compartment and escorted me to a pair of metal detectors so I could demonstrate that I wasn’t carrying any other electronics. A different guard drove me on a narrow access road to a switchback-laden stairway that climbed 800 steps up a mountainside, through buzzing clouds of blue dragonflies, to a platform overlooking the observatory.

Until a few months before his death this past September, the radio astronomer Nan Rendong was the observatory’s scientific leader, and its soul. It was Nan who had made sure the new dish was customized to search for extraterrestrial intelligence. He’d been with the project since its inception, in the early 1990s, when he used satellite imagery to pick out hundreds of candidate sites among the deep depressions in China’s Karst mountain region. Apart from microwaves, such as those that make up the faint afterglow of the Big Bang, radio waves are the weakest form of electromagnetic radiation. The collective energy of all the radio waves caught by Earth’s observatories in a year is less than the kinetic energy released when a single snowflake comes softly to rest on bare soil. Collecting these ethereal signals requires technological silence. That’s why China plans to one day put a radio observatory on the dark side of the moon, a place more technologically silent than anywhere on Earth. It’s why, over the course of the past century, radio observatories have sprouted, like cool white mushrooms, in the blank spots between this planet’s glittering cities. And it’s why Nan went looking for a dish site in the remote Karst mountains. Tall, jagged, and covered in subtropical vegetation, these limestone mountains rise up abruptly from the planet’s crust, forming barriers that can protect an observatory’s sensitive ear from wind and radio noise. The receiver will train its sensitive algorithms across billions of stars, looking for a beacon. After making a shortlist of candidate locations, Nan set out to inspect them on foot. Hiking into the center of the Dawodang depression, he found himself at the bottom of a roughly symmetrical bowl, guarded by a nearly perfect ring of green mountains, all formed by the blind processes of upheaval and erosion. More than 20 years and $180 million later, Nan positioned the dish for its inaugural observation—its “first light,” in the parlance of astronomy. He pointed it at the fading radio glow of a supernova, or “guest star,” as Chinese astronomers had called it when they recorded the unusual brightness of its initial explosion almost 1,000 years earlier.

After the dish is calibrated, it will start scanning large sections of the sky. Andrew Siemion’s seti team is working with the Chinese to develop an instrument to piggyback on these wide sweeps, which by themselves will constitute a radical expansion of the human search for the cosmic other. Siemion told me he’s especially excited to survey dense star fields at the center of the galaxy. “It’s a very interesting place for an advanced civilization to situate itself,” he said. The sheer number of stars and the presence of a supermassive black hole make for ideal conditions “if you want to slingshot a bunch of probes around the galaxy.” Siemion’s receiver will train its sensitive algorithms on billions of wavelengths, across billions of stars, looking for a beacon.

Jon Juarez

Liu Cixin told me he doubts the dish will find one. In a dark-forest cosmos like the one he imagines, no civilization would ever send a beacon unless it were a “death monument,” a powerful broadcast announcing the sender’s impending extinction. If a civilization were about to be invaded by another, or incinerated by a gamma-ray burst, or killed off by some other natural cause, it might use the last of its energy reserves to beam out a dying cry to the most life-friendly planets in its vicinity. Even if Liu is right, and the Chinese dish has no hope of detecting a beacon, it is still sensitive enough to hear a civilization’s fainter radio whispers, the ones that aren’t meant to be overheard, like the aircraft-radar waves that constantly waft off Earth’s surface. If civilizations are indeed silent hunters, we might be wise to hone in on this “leakage” radiation. Many of the night sky’s stars might be surrounded by faint halos of leakage, each a fading artifact of a civilization’s first blush with radio technology, before it recognized the risk and turned off its detectable transmitters. Previous observatories could search only a handful of stars for this radiation. China’s dish has the sensitivity to search tens of thousands.

In Beijing, I told Liu that I was holding out hope for a beacon. I told him I thought dark-forest theory was based on too narrow a reading of history. It may infer too much about the general behavior of civilizations from specific encounters between China and the West. Liu replied, convincingly, that China’s experience with the West is representative of larger patterns. Across history, it is easy to find examples of expansive civilizations that used advanced technologies to bully others. “In China’s imperial history, too,” he said, referring to the country’s long-standing domination of its neighbors. But even if these patterns extend back across all of recorded history, and even if they extend back to the murky epochs of prehistory, to when the Neanderthals vanished sometime after first contact with modern humans, that still might not tell us much about galactic civilizations. For a civilization that has learned to survive across cosmic timescales, humanity’s entire existence would be but a single moment in a long, bright dawn. And no civilization could last tens of millions of years without learning to live in peace internally. Human beings have already created weapons that put our entire species at risk; an advanced civilization’s weapons would likely far outstrip ours. I told Liu that our civilization’s relative youth would suggest we’re an outlier on the spectrum of civilizational behavior, not a Platonic case to generalize from. The Milky Way has been habitable for billions of years. Anyone we make contact with will almost certainly be older, and perhaps wiser. Jon Juarez Moreover, the night sky contains no evidence that older civilizations treat expansion as a first principle. seti researchers have looked for civilizations that shoot outward in all directions from a single origin point, becoming an ever-growing sphere of technology, until they colonize entire galaxies. If they were consuming lots of energy, as expected, these civilizations would give off a telltale infrared glow, and yet we don’t see any in our all-sky scans. Maybe the self-replicating machinery required to spread rapidly across 100 billion stars would be doomed by runaway coding errors. Or maybe civilizations spread unevenly throughout a galaxy, just as humans have spread unevenly across the Earth. But even a civilization that captured a tenth of a galaxy’s stars would be easy to find, and we haven’t found a single one, despite having searched the nearest 100,000 galaxies.

Some seti researchers have wondered about stealthier modes of expansion. They have looked into the feasibility of “Genesis probes,” spacecraft that can seed a planet with microbes, or accelerate evolution on its surface, by sparking a Cambrian explosion, like the one that juiced biological creativity on Earth. Some have even searched for evidence that such spacecraft might have visited this planet, by looking for encoded messages in our DNA—which is, after all, the most robust informational storage medium known to science. They too have come up empty. The idea that civilizations expand ever outward might be woefully anthropocentric. Liu did not concede this point. To him, the absence of these signals is just further evidence that hunters are good at hiding. He told me that we are limited in how we think about other civilizations. “Especially those that may last millions or billions of years,” he said. “When we wonder why they don’t use certain technologies to spread across a galaxy, we might be like spiders wondering why humans don’t use webs to catch insects.” And anyway, an older civilization that has achieved internal peace may still behave like a hunter, Liu said, in part because it would grasp the difficulty of “understanding one another across cosmic distances.” And it would know that the stakes of a misunderstanding could be existential. First contact would be trickier still if we encountered a postbiological artificial intelligence that had taken control of its planet. Its worldview might be doubly alien. It might not feel empathy, which is not an essential feature of intelligence but instead an emotion installed by a particular evolutionary history and culture. The logic behind its actions could be beyond the powers of the human imagination. It might have transformed its entire planet into a supercomputer, and, according to a trio of Oxford researchers, it might find the current cosmos too warm for truly long-term, energy-efficient computing. It might cloak itself from observation, and power down into a dreamless sleep lasting hundreds of millions of years, until such time when the universe has expanded and cooled to a temperature that allows for many more epochs of computing.

As I came up the last flight of steps to the observation platform, the Earth itself seemed to hum like a supercomputer, thanks to the loud, whirring chirps of the mountains’ insects, all amplified by the dish’s acoustics. The first thing I noticed at the top was not the observatory, but the Karst mountains. They were all individuals, lumpen and oddly shaped. It was as though the Mayans had built giant pyramids across hundreds of square miles, and they’d all grown distinctive deformities as they were taken over by vegetation. They stretched in every direction, all the way to the horizon, the nearer ones dark green, and the distant ones looking like blue ridges. Amid this landscape of chaotic shapes was the spectacular structure of the dish. Five football fields wide, and deep enough to hold two bowls of rice for every human being on the planet, it was a genuine instance of the technological sublime. Its vastness reminded me of Utah’s Bingham copper mine, but without the air of hasty, industrial violence. Cool and concave, the dish looked at one with the Earth. It was as though God had pressed a perfect round fingertip into the planet’s outer crust and left behind a smooth, silver print. I sat up there for an hour in the rain, as dark clouds drifted across the sky, throwing warbly light on the observatory. Its thousands of aluminum-triangle panels took on a mosaic effect: Some tiles turned bright silver, others pale bronze. It was strange to think that if a signal from a distant intelligence were to reach us anytime soon, it would probably pour down into this metallic dimple in the planet. The radio waves would ping off the dish and into the receiver. They’d be pored over and verified. International protocols require the disclosure of first contact, but they are nonbinding. Maybe China would go public with the signal but withhold its star of origin, lest a fringe group send Earth’s first response. Maybe China would make the signal a state secret. Even then, one of its international partners could go rogue. Or maybe one of China’s own scientists would convert the signal into light pulses and send it out beyond the great firewall, to fly freely around the messy snarl of fiber-optic cables that spans our planet.

In Beijing, I had asked Liu to set aside dark-forest theory for a moment. I asked him to imagine the Chinese Academy of Sciences calling to tell him it had found a signal. How would he reply to a message from a cosmic civilization? He said that he would avoid giving a too-detailed account of human history. “It’s very dark,” he said. “It might make us appear more threatening.” In Blindsight, Peter Watts’s novel of first contact, mere reference to the individual self is enough to get us profiled as an existential threat. I reminded Liu that distant civilizations might be able to detect atomic-bomb flashes in the atmospheres of distant planets, provided they engage in long-term monitoring of life-friendly habitats, as any advanced civilization surely would. The decision about whether to reveal our history might not be ours to make. Liu told me that first contact would lead to a human conflict, if not a world war. This is a popular trope in science fiction. In last year’s Oscar-nominated film Arrival, the sudden appearance of an extraterrestrial intelligence inspires the formation of apocalyptic cults and nearly triggers a war between world powers anxious to gain an edge in the race to understand the alien’s messages. There is also real-world evidence for Liu’s pessimism: When Orson Welles’s “War of the Worlds” radio broadcast simulating an alien invasion was replayed in Ecuador in 1949, a riot broke out, resulting in the deaths of six people. “We have fallen into conflicts over things that are much easier to solve,” Liu told me.