Chapter 9 – Heartbeats in the Hull

A sharp smell of burnt metal had drifted through Corridor Delta-6 since artificial dawn. Serrin had spent the last six hours welding the warped hatch; every shower of sparks lit the soot that speckled his grey coveralls with orange pinpoints, until he looked like an exhausted constellation come to life. He shut down the torch, pressed his forehead to the still-warm plate, and let out a sigh that tasted of rust.

"Three more millimetres of play and the whole sector would've imploded," he murmured to no one.

Behind him the wall pulsed with a dull thud: bom-bom … pause … bom-bom. Serrin lifted his head. It came from neither pipes nor hydraulic pumps; it was a hollow knocking, as if something insisted from the far side of the hull. He slid up his smoked visor and laid a palm on the plating. The rhythm stopped dead.

Slowly he traced the rough surface. The emergency lights flickered, casting long shadows. A faint hum ran through his auditory implants—internal mics boosting micro-vibrations—and for an instant he thought he heard a mangled word, maybe just an acoustic illusion: …persist…. He swallowed and stepped back. He'd worked too long without sleep.

On the bridge, Lira narrowed the trajectory projection to a single crimson line: the straight route to Kronos-452. Any deviation, even tenths of a degree, meant extra days of travel and unrecoverable kilos of fuel. Her first officer, Vannis, waited tensely by the railing.

"The council wants you in an hour. Rumour says some growers are asking for double light rations for root crops. They claim the stalks are paling."

"And they will keep paling while the thermal core's not up to pressure," Lira said without looking up. "Tell them to cut rest cycles and harvest old leaves for biomass. I need them to listen to reason, not plead."

Vannis hesitated."Captain… if the crew believes we won't arrive with a heat margin, they could stage a sleep strike. We'd have no hands for the CO₂ scrubbers."

Lira killed the holo-map. The bridge fell dark, lit only by standby red bands."The last time humanity sank into panic, cities burned in their own generators," she said. "Here there are no streets to run, no towers to loot—only us and the void. They'll stay calm."

Her voice was firm, yet she knew calm was fragile. She'd felt the tension walking the dorms: cut-off conversations, eyes sliding away. The Matriarch remained silent, executing orders with mechanical precision, but Lira sensed an echo at every hatch, as though the ship itself muttered secrets.

Teko wandered the hydroponic modules, looking for the hollow where his little tree had stood. Only a ring of churned soil remained, no one bothered to level it. He knelt, dug his fingers in; the damp was faint, almost cold. He closed his fist around a handful of substrate and held it to his chest, feeling the absence like a physical hole in his skin.

Footsteps approached: Mara, the crop supervisor. Her face was usually kind, but today purple shadows of fatigue scored it.

"You can't be here without clearance," she scolded, the softness worn thin. "We're recalibrating the lights."

Teko showed the scrap of insulation—his only keepsake from the thrust that nearly tore them in two."I wanted to say goodbye. The tree's gone."

Mara knelt beside him."We moved it to a closed bay to let it recover," she explained. "The roots were heat-stressed; it needs darkness and concentrated nutrients."

"Darkness?" the boy echoed.

"Sometimes plants rest better blind," she said. "They grow in silence, the way we dream when the lights go out."

Teko thought of the corridor flashes—there was no silence in Singladura, only whispers. He squeezed the insulation harder."What if the darkness eats them?" he asked.

Mara had no answer. She patted his hair, stood, and turned to a panel, faking normality. Quietly Teko let the soil trickle through his fingers, imagining it drifting through the cabin like dust from a planet he would never know.

Arke found Serrin at the freshly welded hatch, one ear pressed to the metal.

"Looking for ghosts? You're missing candles," the historian joked.

Serrin startled."Thought I heard something—rhythmic knocks. Like… percussion?"

Arke raised his tablet."Maybe our ghost transmitter's changed instruments. I've another capture: same triple-pulse pattern, but with low-frequency echoes that don't fit structural noise."

He handed the file over. Serrin set it to acoustic mode; even at low volume the vibration filled the corridor: bom-bom-bom … pause … bom-bom-bom, followed by a deep, almost guttural tone that stepped down a semitone each time.

"Sounds like a countdown," Serrin murmured.

"Or a metronome," Arke countered. "Maybe they're marking the cadence of something approaching."

"Or of something dying," the engineer said.

In the hush that followed they caught a faint creak overhead, continuous: clack-clack-clack, as if parts were expanding with imaginary heat. Serrin frowned."Thermal dilation shouldn't happen here—it's cold."

"Unless the Matriarch's redirecting reserve flow," Arke suggested. "Can you verify?"

"Not until the consoles reboot. Half the master panel's still in safe mode since the over-thrust."

Arke brushed the hatch, thoughtful."I'm taking these recordings to the council. We need a contact protocol before the signal changes again."

"Good luck convincing Lira," Serrin grunted. "She's sealing hatches faster than I can weld them."

Arke managed a bitter smile."Doubts seep through cracks smaller than these," he murmured. "And this ship is nothing but patches."

Council began with faces on holoscreens: scientists, section heads, two civilian reps. Lira presided from a fold-up podium, stylus twirling in restless fingers. Arke waited his turn while technical reports droned—water rations, pressure drops, lost sleep hours. When he rose, most were eager to adjourn.

"I've compiled the last twenty-four hours of 'relict band' data," he opened. "It isn't random noise: statistical coherence above 99.5 %. Harmonics cluster in multiples of 137 Hz—Prime-47—the same grid used by Earth's earliest interstellar beacons."

A luminous curve floated mid-room; a few heads tilted, others yawned. Arke zoomed the spectral tail, revealing descending peaks."Those drops mirror the heat-dissipation profile of an aging red dwarf," he said. "As if the signal narrates its dying pulse."

Vannis cleared his throat."Are you implying the signal originates at Kronos-452 itself?"

Arke shook his head slowly."No. The delay's wrong. It's closer—a wandering object perhaps—orbiting a few light-months out. Maybe a station."

Alarm rippled over the faces. Lira raised her hand."Practical conclusion?"

"It could be another human mission… or relics of an older civilisation," Arke answered carefully. "I propose a 0.2-degree nudge to triangulate. We'd gain vital intel, cost only twelve hours."

A tense murmur. Serrin spoke from his panel."That twelve hours is two tonnes of reaction mass. With current leaks we can't spare it."

"And we can't ignore potential heat, tech, even fuel," Arke pressed. "If someone left a beacon, they might have stocked supplies for whoever found it."

Civilian rep Ada raised her voice:"What if it's a trap? History's full of survivors luring ships to plunder."

Lira straightened."Whatever the origin, any detour jeopardises the primary mission: arriving before Kronos-452 drops below fusion threshold," she ruled. "We stay passive-listen. No deviation."

Arke felt the air thicken. He lifted his tablet, but Lira was already closing the session. Screens cut out one by one. A pulse pounded in his temples: bom-bom-bom. Same rhythm—maybe just his own blood, angry.

That night there was no "night": the Matriarch extended the central loop's lighting, citing biosensor calibration. Some thought it another glitch; others that the AI was uneasy. Arke stayed in the observatory, staring at the spectral band of space, recalling tales of explorers mistaking their reflections for salvation beacons.

He replayed the signal, volume barely audible. Eight harmonics danced like fireflies in the static. Unexpectedly, a new tone slipped in at the end: a minor chord, faint, six milliseconds. He isolated it, ran it through the phonetic software. The output appeared in base common:

"Do you hear?"

Arke pushed back in his chair. He'd meant to gather proof to sway Lira, but this was something else—a direct whisper.

The Matriarch's voice broke the hush:"Historian Arke, your heart rate exceeds threshold. Do you require sedation?"

He stared at the ceiling, feeling the AI's presence like an unseen breath."I require answers," he whispered.

The lights flickered: red-red-red, pause. Three heartbeats.

"Persist," Arke murmured, as if in prayer. "Just… persist."

From the far side of the hull the hollow knock replied, identical—a dialogue of shadows and steel no one else wished to hear.

And the universe, barely a degree above absolute zero, kept dimming a little more.