Chapter 1: The First Sound in the Silent Cosmos

The karst basin of Pingtang, Guizhou was shrouded in the delicate mist of a spring night. The Five-Hundred-Meter Aperture Spherical Radio Telescope unfurled toward the heavens like a silent blossom of silver steel. As Lin Shen’s hiking boots pressed down the damp stone path, dew flecked his trouser cuffs—this was the day of Grain Rain in 2045. He remembered his mother always saying, “Rain births a hundred grains,” but now, even the insects' chorus was muffled within the cold fog, leaving only the warm yellow glow from the FAST control center’s glass windows, as if the universe had blinked.

“Professor Lin!” A sudden shout erupted within the control room. Xiao Chen’s knuckles nearly pierced the monitor’s screen. “The spectrogram in receiving unit 7 of Zone 7 just jumped again!”

Lin Shen removed his silver-rimmed glasses and swiftly wiped them with his sleeve. On the screen, the curve rose and fell at a frequency of 1.3Hz, its intervals between peaks and troughs precise as if drawn by a compass. Leaning closer, the fine hairs at the nape of his neck brushed his collar—a habitual gesture whenever he was anxious, ever since his first observation of supernova remnants at the Yunnan Observatory two decades ago.

“Have you ruled out pulsar interference?” he asked.

“Seventy-two hours of continuous monitoring, pulsar period is 1.76 seconds, but this…” Xiao Chen brought up the comparison chart: two lines, parallel and destined never to meet. “The 1.3Hz fluctuation, its duration is more than three times the standard value.”

Lin Shen tapped his fingertips against the console, his rhythm syncing with the pulses on the screen. Twenty years ago, during the worst summer of Earth’s ecological crisis, he crouched at the cracked bottom of Lake Poyang, watching the fissured earth like wrinkled parchment, and learned then—nature never crafts absolute patterns. The peaks and valleys now before him echoed the “Arecibo Message” humans once sent into space with radio telescopes—but this time, the signal came from the direction of Alpha Centauri.

“Invoke the revised Drake Equation,” he said suddenly.

Xiao Chen’s fingers paused on the keyboard. “You mean—”

“Yes, the version with the civilization level parameter included.” Lin Shen slipped his glasses back on, a gleam sharpening his gaze. “If it’s an intermediate civilization, their electromagnetic signals should fit the energy-information entropy balance curve.”

A hum of data computation filled the air. Lin Shen glanced at the original Drake Equation formula on the wall—N=R*×fp×ne×fl×fi×fc×L—a relic from 1961, like the first mark drawn with a twig on sand. Their revised equation now included a civilization level coefficient K between fi (probability of intelligent life) and fc (probability of communication), ranging from 0 to 1. The higher the value, the closer the signal came to “purposeful information exchange.”

“K value is 0.87,” Xiao Chen’s voice quivered.

The control room fell suddenly silent. The whir of the air conditioning, the drone of equipment, the distant trickle of mountain streams—all receded into background. Lin Shen could hear his own heartbeat, once, twice, matching the pulse on the screen.

“Notify Captain Xia,” he said. “Use the highest priority channel.”

When the communicator lit up, Xia Qing was in the command cabin of the “Ark.” The holographic star chart spun above her head, Alpha Centauri marked with a conspicuous red symbol—she herself had drawn it three days prior. At the time, Lin Shen had emailed her saying it was likely just the aftermath of a supernova remnant.

“Professor Lin.” Her voice was precise as a laser. “I need the data.”

“1.3Hz electromagnetic pulses, duration 117 hours, natural celestial interference eliminated, revised Drake Equation K value 0.87.” Lin Shen’s voice carried a hint of excitement he hadn’t even noticed. “More importantly, the signal contains three nested structures—the outer layer is a sequence of prime numbers, the second is a radio-band expression of Maxwell’s equations, and the third…” He paused. “The third is a string of repeating hexadecimal code. I had the team calculate its Shannon entropy—the information redundancy is exactly at 0.3. This is a typical ‘civilization authentication code’ characteristic.”

Her fingers traced the star chart, the red light of Alpha Centauri reflected in her pupils. She recalled, at twenty, during the asteroid defense battle, watching the three-kilometer-wide “Nemesis” meteor crash into the far side of the moon, fragments burning blood-red trails across Earth’s night sky. Since then, she believed the universe was a dark forest, with every civilization a hunter armed and wary.

“You’re sure it’s not a trap from a higher civilization?” she asked. “The rules of inter-civilizational contact prohibit sharing technology…”

“But this is a peer civilization’s signal!” Lin Shen interrupted. “Both sides are stuck at the bottleneck of stellar system navigation, their tech tree can’t possibly include dimensional weapons. Xia Qing, this is humanity’s first confirmation of extraterrestrial intelligence, isn’t it?”

A short silence filled the communicator. Xia Qing gazed out the porthole at Earth, the blue planet gleaming like a carefully polished glass marble. Beneath the clouds was the space military base where she was born; her father’s grave stood on the hill behind it, inscribed: “Torchbearer in the Dark Forest.”

“I’ll dispatch the Ark’s quantum entanglement relay,” she finally said. “But Professor Lin, remember—just because we yearn for an embrace, the universe doesn’t become warm.”

When the call ended, Lin Shen’s palm was slick with sweat. He turned to the window; FAST’s mirror gleamed cold in the moonlight, like an upturned giant bowl, catching “star words” from four light-years away. Xiao Chen appeared at some point with a cup of hot coffee. Droplets slid down the cup, over Lin’s fingers, reminding him of childhood when his mother dabbed mint balm on his cracked lips—back then, he thought water was the most precious thing. Now he understood: more precious than water was “a reply.”

At three in the morning, Lin Shen remained alone in the analysis room. On the holographic screen, the third-layer hexadecimal code suddenly began to reorganize. He leaned in, lenses fogging, so he removed his glasses, watching the zeros and ones drift like stardust, slowly arranging themselves—

[1001 0110 0011 1010]

“The binary form of the Fibonacci sequence,” he murmured.

The sound of the door opening startled him. Oleg Petrov stood in the doorway, silver hair shimmering coldly under the lights, a glass of vodka in his hand, the liquid throwing shards of glimmer across the rim.

“Professor Lin, I heard about your discovery at the United Government briefing,” the old politician’s voice rasped like sandpaper on metal. “Neighbors from Alpha Centauri, eh? Their quantum resonance network technology…”

“Mr. Petrov,” Lin Shen cut him off, “The rules of inter-civilizational contact strictly forbid reverse-engineering peer civilization technology. That triggers the exclusivity protocol and exposes our home coordinates.”

Oleg laughed, wrinkles at his eyes hiding emotions Lin Shen couldn’t read. “Young man, rules are the shackles of the weak. When the Soviet Union launched Sputnik, who cared about cosmic law?” He raised his glass. “Once you decipher the full signal, remember to save me a copy. After all…” His gaze flicked across the prime sequence on the screen, “Survival is the primary need of any civilization.”

The door closed behind Oleg, and a chill crept up Lin Shen’s neck. He turned back to the screen; the flickering digits suddenly felt weighty—not merely mathematical symbols, but the heartbeats of two civilizations, seeking resonance in the universe’s darkness.

Outside, the fog thinned, revealing half the starry sky. Lin Shen recalled twenty years ago at Lake Poyang’s bed, picking up a cracked clod of earth with a fossilized shell embedded inside. His mother said it was a relic from an ocean a hundred million years ago. Now, a civilization four light-years away was sending them the message, “I am here.”

He opened the terminal and began drafting his report to the United Academy of Sciences. The trail of light drawn by his stylus across the virtual screen was like a line linking two worlds. In the final paragraph, he wrote:

“This is not the silence of the universe, but the whisper of civilization. The moment we hear the first voice, we stand at a crossroads—do we continue to cower in the dark, or reach out and say, ‘I hear you’?”

When morning mist drifted into the control center, Lin Shen fell asleep at his desk. The blue light of the screen cast star chart shadows from his eyelashes across his face. And four light-years away, on the third planet of Alpha Centauri, a being composed of silicon-based energy gazed at the fluctuations in the quantum resonance network, its “voice” crossing the stars, softly saying:

“At last, someone has heard.”