Chapter 5: Road to the Center
Table of Contents
The Thread launched from Ceres orbit in the spring of 2158, twenty-three years after a ranch astronomer had lied his way onto a survey ship and changed the course of human history.
Its crew had been assembled with the same instinct Nolan had once brought to anomaly detection — each person chosen because their work predicted a specific piece of what lay ahead.
Captain Tomás Herrera commanded. A steady, quiet presence who asked practical questions and had piloted more wormhole transits than anyone alive. He had a wife and two sons in the orbital habitats above Ceres, and he wrote to them every evening in a small leather journal he kept in his quarters — not transmissions, just letters, written by hand, that he would deliver in person when he returned. He had the unhurried competence of a man who had never needed to raise his voice to be obeyed, and the self-discipline to keep his own wonder in check when duty required it. Nolan had the self-awareness to know he needed someone like Herrera — someone whose competence was invisible because it never had to become dramatic.
He had been a cargo pilot before he was a captain — long-haul runs between Earth and the Belt, the unglamorous infrastructure of a civilization learning to live past its cradle. His first wormhole transit had been on an early survey mission, three years after the Meridian’s crossing, and he had never told anyone what it did to him. Eleven seconds in the throat, the stars smearing, the hull groaning around him like a ship in heavy weather — and then the exit, and a sky full of wrong constellations, and a feeling that arrived without words and settled into his body like ballast. Not wonder. Nothing so noisy as wonder. More like the sensation of a compass needle finding north: a quiet, physical certainty that this was the direction his life was supposed to face. He had written to his wife that evening — not about the stars or the science, but about the feeling. She had written back: Just make sure you can always find your way home. He kept the letter in the journal’s back cover, behind the pages he was filling for his sons. The first promise and the last instruction.
Before every transit since — every wormhole, every departure, every threshold — Herrera performed the same small ritual: he would close the leather journal, place his palm flat on the cover for a moment, then stow it in the drawer beside his bunk. He never explained it. The crew would come to recognize the soft sound of the drawer closing as the signal that the captain was ready, and that whatever lay on the other side of the next door, he intended to come back through it.
Three weeks before launch, Herrera received a communication from Commander Lena Vasik.
She was direct. She had heard who was funding and architecting the mission, and she had something to say that would not fit in an official channel. Herrera listened from his quarters at Ceres, the Thread visible through his viewport, its hull catching the light of a sun that was just another star from this distance.
“He was the perfect passenger for eighteen months,” Vasik said. Her voice carried no anger — that had been spent years ago. What remained was something colder and more useful: precision. “Helpful. Deferential. Never once overstepped. And every day of those eighteen months, he was carrying a secret that could have killed us all, waiting for the exact moment when I had no option but to comply.”
She paused.
“He will do this to you. Not the same way — he’s too intelligent to repeat a method. But at the moment it matters most, when the stakes are highest and your judgment says stop, he will find a way to override you. It isn’t malice, Tomás. It’s worse than malice. He genuinely believes the destination justifies anything he does to reach it. And the hell of it is that he might be right about the destination. He was right about the wormhole. He’ll probably be right about whatever’s at the center. But being right about where to go doesn’t make him safe to travel with.”
Herrera thanked her. He meant it — he respected Vasik, as did everyone who had ever served under her or alongside her. He filed the warning in the place where he kept things that mattered, and he did not dismiss it.
But he also did not cancel the mission. The science was real. The topology was compelling. And Herrera believed — with the quiet confidence of a man who had commanded crews through a hundred wormhole transits — that he could manage one civilian, however brilliant, however driven. He had managed worse.
He would remember this conversation later, in circumstances Vasik had predicted with the accuracy of a woman who had seen the future once already and been unable to prevent it.
Dr. Ren Hakoda, who had gone from reluctant correspondent to co-author to something neither man would call friendship but both relied on. He had left the Ares Orbital Research Station without hesitation when Nolan offered him a berth — the man who had named the Lacework in an offhand remark at two in the morning wanted to see where the threads converged. He had a dry, self-deprecating humor that surfaced only in private — a tendency to describe the most extraordinary discoveries in the language of mild inconvenience, as if a traversable wormhole were a scheduling conflict. Upon seeing the first Trunk Line data — three kilometers of engineered spacetime anchored near a red giant older than Earth — his only comment had been: “Well. That’s going to be difficult to cite properly.” It was his way of staying sane in the presence of things that should have broken the mind’s capacity for scale. The moments when the humor failed — when it simply wasn’t there — were the moments the crew learned to fear.
He had been married, briefly, to a materials scientist on Ares — a woman named Lian who had understood him better than he’d understood himself. She left after two years. “You’re not absent-minded, Ren,” she’d told him. “You’re absent-hearted. Everything you actually care about is thirteen hundred light-years away.” He had not corrected her, because she was right, and the quiet precision of her diagnosis had settled into him the way good data does: undeniable, clarifying, and slightly too late to be useful. He kept no photograph. He kept the topology map.
Dr. Adaeze Obi, who had proven on Viridis that life across the galaxy shared a common origin and who had spent the decade since cataloguing that shared biochemistry across sixty-four worlds. She had identified the biological gradient that supported the convergence theory — life grew older and more complex the deeper you traveled — and she wanted to follow that gradient to its source. She wrote letters to her daughter Ife, who was fourteen now and lived with Adaeze’s mother in Nairobi, who understood that her mother was leaving for a journey that might take years, and who had said, with the devastating clarity of a teenager: Just come back. Adaeze kept the letter folded in the pocket of her lab coat. She touched it sometimes when she thought no one was looking.
Dr. Yuki Taniguchi, who had coined the term “Throat Engine” and who wanted to study the ancient construction machinery at scales no survey mission had yet attempted. She hummed while she worked — always the same melody, a lullaby her grandmother had sung in the kitchen of a small house in Sapporo, its words lost to childhood but its contour preserved in muscle memory, rising and falling in three notes, a pause, three notes, a pattern the crew came to know as well as the ship’s own sounds. Steady humming meant concentration. Silence meant trouble. A sudden stop meant she had found something that frightened her. She had been taking things apart since she could hold a screwdriver — her father’s watch, the family rice cooker, her older sister’s bicycle derailleur — not to break them but to understand the conversation between their parts. She always put them back together, usually better. Machines, she had decided at an age when most children were deciding on favorite colors, were honest in a way that people rarely managed: they did exactly what their design allowed, no more, no less, and if they failed it was because someone had asked them to do something they were never built for. She spoke to the Thread the way she spoke to every machine she’d ever worked on — matter-of-factly, without sentimentality, a running monologue of encouragement and negotiation that the crew overhead through open hatches and learned not to find strange. “I know,” she’d murmur to a reluctant sensor array, adjusting its calibration with patient fingers. “Give it a minute. You’ll get there.”
And Dr. Maren Solberg.
Nolan had found Solberg’s work during the long years on Deimos Station, reading everything published on wormhole construction theory while watching survey ships depart through his observation port. Maren was a theoretical cosmologist at the University of Oslo, and her papers were the kind that received seventeen citations — fifteen from researchers who had not read the mathematics and two from those who had and found them uncomfortably plausible.
Her thesis was breathtaking in scope and unsettling in implication: that an advanced civilization would propagate across galactic distances not by sending physical probes but by sending information. Seed signals — electromagnetic transmissions of extraordinary power and precision, carrying compressed blueprints for everything needed to bootstrap infrastructure at a destination. Construction sequences. Computational substrates. Entangled quantum states for wormhole tethering. Each signal, upon encountering a sufficiently rich material environment — a star, a molecular cloud, a planetary nebula — would trigger a cascading process of self-assembly: the signal’s interaction with ambient matter building, layer by layer, the machinery encoded in its own structure.
No receiver station. No physical hardware transported across the void. Just light, carrying the instructions for its own reception.
“The network doesn’t require a builder at every node,” Maren had written in the paper that had drawn Nolan’s attention across a decade of solitary reading. “It requires a builder at the first node and a signal at every subsequent one. Each hub, once bootstrapped, becomes a new launcher — sending its own seed signals to more distant targets, carrying fresh entanglement resources, propagating the network outward at c. The topology is self-propagating. The frontier is self-extending. The builders need only start it. The network does the rest.”
Her framework predicted a hierarchical, convergent topology: the oldest and most sophisticated infrastructure at the center, the youngest and simplest at the edges, the whole structure pointing homeward like a river system flowing to the sea. It predicted self-similar architecture at every scale — each hub a miniature version of the one closer to the origin, with lateral connections to its neighbors and one conspicuously larger gate pointing inward.
When Nolan had read those predictions and compared them to the Lacework’s actual topology — the convergence, the hierarchy, the Trunk Lines all pointing toward the galactic center — the hair on his arms had stood up. He contacted Maren the same day.
She had been skeptical of him. A civilian with no institutional standing and a documented history of deception. He had won her over with data: the convergence topology matched her model precisely, the wormhole stability profiles were consistent with Casimir-cavity construction bootstrapped from seed signals, and the mission he proposed — following the Trunk Lines to the center — was the experimental test her theory had always needed and could never get.
She joined within a month. Quiet, precise, comfortable at the speculative edge of physics in a way that made the rest of the crew slightly uneasy. She had the demeanor of someone who had spent a career being right about things nobody was ready to hear, and who had learned to wait. She was an insomniac — had been since childhood, since the long polar nights in Bergen when she would lie in bed with the darkness pressing against the windows and her mind refusing to quiet. Her mother would find her at the kitchen table at four in the morning, a nine-year-old writing equations on the backs of grocery receipts, and would sit with her without speaking, because she had learned that Maren’s wakefulness was not distress but simply the way her daughter was built — a mind that did not have an off switch, that ran the universe continuously the way other people’s hearts ran their blood. She walked the Thread’s corridors at night, tablet in hand, and if you encountered her at three in the morning she would look at you with the mild surprise of a woman who had forgotten other people existed — not unfriendly, just genuinely startled that the universe contained something besides the equation she was working on. The margins of her tablet were filled with sketches — not art, but diagrams. Network topologies, propagation wavefronts, the branching geometry of systems she had predicted since her doctoral work. She drew the way other people doodled: unconsciously, compulsively, her stylus tracing the shapes of things she was thinking about, leaving a fossil record of a mind that never stopped building models of the world.
In the weeks before departure, Nolan was everything a mission architect should be. He deferred to Herrera on every operational question. He consulted the science team on survey priorities and incorporated their feedback with visible gratitude. He brought Ren coffee during late-night topology sessions and asked Adaeze about her daughter and listened to Maren’s theoretical frameworks with the attentiveness of a student, not a patron. He was generous, self-effacing, and careful — and if you had served on the Perspicacity, you would have recognized every note of the performance, because it was the same one he had played for eighteen months in the outer solar system, pitch-perfect, not a single tell.
Whether it was a performance this time — whether some part of Nolan Cade had genuinely learned to share a mission rather than commandeer it — was a question that would not be answered until the moment when it mattered most.
One evening during the second week of the voyage, after a wormhole had deposited them in a system with twin red dwarfs and a gas giant ringed in pale methane ice, the crew gathered in the Thread’s common room for what Ren would later call — with characteristic precision — “the last genuinely good meal aboard this ship.”
Yuki had modified the galley’s protein synthesizer to produce something approximating yakitori, a feat of engineering she was more visibly proud of than any of her sensor calibrations. She hummed as she served — the lullaby rising and falling in the warm air — and Herrera, who had closed his journal and pressed his palm to its cover before stowing it with the quiet finality that preceded every departure, accepted his plate with a nod of thanks.
Ren ate with his left hand, the right occupied with a tablet displaying the topology of the next three hops. “I should note,” he said, studying a Trunk Line whose age estimate exceeded the formation of Earth’s sun, “that my original research proposal described this work as ‘a systematic survey of wormhole network morphology.’ I believe the reviewers would be surprised by the field methodology.”
“The reviewers would be unconscious,” Yuki said, not looking up from the synthesizer.
Adaeze laughed — a sound that seemed to startle her, as if she’d forgotten its shape. She had been quieter since the launch, the letter from Ife settling into her like a weight she was learning to carry rather than hold. But tonight the common room was warm and the protein approximation was decent and the red dwarfs outside the viewport painted the hull in amber, and she told them about Ife’s first word. Not mama or baba but moon — oṣùpá in Yoruba — pointing at the sky through the window of her grandmother’s house in Nairobi, eleven months old. “The first thing she named,” Adaeze said, “was the thing farthest away.”
Maren looked up from her tablet, where her stylus had been tracing network diagrams in the margins. “That might be the most human thing I’ve ever heard.”
Nolan listened. He asked Adaeze about Ife’s school, about whether she liked science. He asked Herrera about his sons — their names, their ages, what they wanted to be when they grew up. He asked Ren about a paper he’d read and disagreed with, framing his disagreement as a question, giving Ren the pleasure of dismantling the argument himself. He asked Yuki how she’d coaxed the synthesizer into compliance, and listened to her answer with genuine interest. He asked Maren about a wrinkle in her seed signal framework that had been troubling him, and her eyes lit up the way they did when someone engaged with the actual mathematics rather than the summary.
He was warm. He was present. He was the best version of himself — the version that had made a fortune in trading because he could read what people needed and provide it, the version that had maintained a lie for eighteen months aboard the Perspicacity without a single crack in the performance. And the crew, who were not fools but who were human, and who were far from home in a ship threading through a network built by something older than the stars, let themselves enjoy it. Because the alternative was to sit in a warm room with good food and refuse to trust the man across the table, and that was a loneliness none of them could afford. Not yet. Not here.
They had entered the Lacework at 97 AU — through the door Nolan had found from a ranch in Wyoming, the first door any human had ever seen. They had emerged in the Viridis system, where Adaeze had proved that life across the galaxy shared a common origin. The secondary wormhole mouths there had already been catalogued by prior survey missions — smaller mouths at the system’s outer edge, each one leading to a different destination in the network. But the Thread was the first crewed vessel to follow them deeper.
At the second hop, the pattern declared itself. Multiple wormhole mouths scattered through the system, each one a different size, each one connecting to a different branch of the network. Ren overlaid the throat dimensions against his topology model and confirmed what the convergence paper had predicted: the largest mouth pointed inward. At every node, the biggest wormhole led closer to the galactic center, deeper into the network’s hierarchy. Smaller mouths branched laterally or outward, connecting to neighboring systems and peripheral routes. The Lacework had been built so that any traveler who followed the widest door would converge on the center. No map required. No instructions. Just the architecture itself, pointing the way.
But the wormholes within each system were not conveniently close. They were separated by vast stretches of ordinary space — mouths positioned in different orbital zones, often tens or hundreds of AU apart. Between hops, the Thread spent weeks in sublight transit, crossing from one mouth to the next at velocities that felt glacial after the eleven-second miracle of a wormhole crossing. Weeks of watching the stars drift imperceptibly, of running surveys and cataloguing the system’s biology, of waiting for the next door to grow from a data signature into a shimmer of distorted starlight on the forward sensors.
The exception was the hub systems. Every few hops, the topology funneled them through a node that was different from the rest — a system with no habitable world, no biology, no garden. Just wormhole mouths, clustered close together, sometimes within days of sublight travel rather than weeks. Pure junctions: gravitationally stable, centrally positioned relative to surrounding routes, optimized for passage rather than life. “The tiered structure,” Ren noted, studying the hub topology at their first such waypoint. “Local capillaries feeding into regional hubs, regional hubs feeding into trunk junctions. It’s exactly the hierarchical routing the convergence model predicted.” The crew came to welcome these systems as waypoints — brief respites from the long sublight transits, where the next door was always close and the only purpose was to keep moving.
The journey took four months — not because of transit time, each wormhole hop a matter of seconds, but because of the weeks of sublight travel between mouths, the careful survey work at each node, and the systematic documentation of a network that had existed longer than the Earth. At every stop, before any transit, Herrera ordered a communications beacon deployed — a small automated relay anchored near the wormhole mouth, maintaining a signal thread back through the network to Earth. Standard protocol: reverse navigation and data relay. But the crew noticed the way he checked the beacon’s telemetry before every departure, the quiet confirmation that the thread home was intact, and understood that for Herrera the beacons were something more than protocol. They were his wife’s instruction, kept in installments: just make sure you can always find your way home. They hopped from Capillary to Bridge to Trunk Line, following the converging topology deeper into the disk of the Milky Way.
Somewhere in those early weeks, they began calling them the Gardeners. No one could identify the precise moment the word acquired a capital letter — it had been Adaeze’s originally, an offhand metaphor in the Meridian’s galley years ago, comparing the network to paths that found their own soil and planted their own seeds. Nolan had adopted it first, with the reverence he brought to everything that confirmed the story he wanted the universe to be telling. Ren had objected once — “We don’t know they were gardeners; we know they built infrastructure and delivered chemistry kits, which is a résumé, not an identity” — and then stopped objecting, because the crew needed a word, and this was the best one they had. By the fourth hop, Herrera was writing it capitalized in his logs, and Adaeze found herself in the odd position of having named something she increasingly suspected she did not understand.
At each node, the infrastructure grew more substantial. The wormhole mouths were larger, older, their stabilization fields more deeply entrenched in the local spacetime geometry. And the Throat Engines — the Casimir cavity arrays Yuki had first identified and named at the 97 AU wormhole, where they had orbited the mouth like buttresses around a cathedral arch — were here on a completely different scale. At 97 AU, the largest had been building-sized. Here, deep in the Trunk Line network, they were the size of small moons.
Yuki had studied the 97 AU Throat Engines for three weeks with the Perspicacity’s instruments. She had published more on their engineering than anyone alive. But those had been the smallest in the network — the outermost, the youngest, tending a wormhole mouth barely two hundred meters across. The Engines orbiting the Trunk Line wormholes were orders of magnitude larger, and their scale revealed structure that the smaller specimens had been too fine to resolve. Surface architecture visible at every scale from kilometers down to what electron microscopy suggested was the Planck length. She studied them with the intensity of a watchmaker who had spent years examining pocket watches and was now standing inside the clock tower.
For Maren, it was a first encounter. She had spent a decade predicting these machines from theory — publishing papers that described their construction principles, their propagation mechanics, their role in the network’s self-assembly — but she had never seen one. She stood at the observation port and watched an Engine drift past, a dark moon etched with structures her models had described but her eyes had never witnessed, and her stylus moved on the tablet’s margin without her noticing, tracing the geometry as it passed.
“They’re maintaining the wormhole geometry,” Yuki reported, “the same vacuum energy conversion we documented at 97 AU. But at this scale I can see how much of the architecture is idle. The Casimir cavity arrays are dynamic — reconfigurable at the atomic level — and they’re operating at a fraction of their capacity. Holding the throat open is the baseline function. These machines were designed for far more than that.”
She found the structure during a close-pass survey of the largest Engine’s equatorial ridge — a linear array running nearly four kilometers along one face, composed of the same reconfigurable metamaterial as the Casimir cavities but arranged in a geometry that was as legible to Yuki as a circuit diagram. Waveguides. Focusing elements. Feed structures tapering to apertures of atomic precision. The architecture of a phased emitter, built to project a coherent electromagnetic beam with a collimation so tight that diffraction losses over interstellar distances would be negligible.
It was dormant. No energy in the feed lattice, no charge in the focusing elements, no emission in any frequency the Thread’s instruments could detect. The array sat in the Engine’s architecture like a speaker in a room where no one was talking — structurally present, functionally silent, its purpose legible in its design but invisible in its operation.
“It’s a beam array,” she told the crew, pulling up the structural scans. “Phased, coherent, designed for directed electromagnetic transmission at interstellar scales. It’s integrated into the Engine’s primary structure — not added, not secondary. The Engine was built around it.” She rotated the scan to show the emitter’s orientation: outward from the wormhole mouth, away from the local star, into open space. “And it’s aimed at nothing. No target in its line of sight for eleven light-years.”
It was Maren who recognized what they were looking at.
She spent days at one Throat Engine site, running analyses that no one else on the ship had the theoretical framework to design. She moved through the data with the focused patience of a woman who had spent years building a model in the dark and was now, for the first time, holding it up to light.
“These weren’t manufactured somewhere and transported here,” she said, presenting her findings to the crew gathered in the Thread’s common room. “The metamaterial shows growth patterns — layer-by-layer atomic deposition, accretional symmetries, dendritic microstructure consistent with programmatic construction from ambient materials.” She paused to let the implication land. “A seed signal built this. An electromagnetic transmission arrived here carrying compressed construction sequences, interacted with the local stellar and interstellar medium, and assembled these structures in place — atom by atom, over centuries. The first layer catalyzed the second. The second catalyzed the third. Self-assembling, self-correcting, from a single initial signal.”
She turned to the scan of Yuki’s beam array, still displayed on the common room screen. “And this is the confirmation. The seed signal doesn’t just build a Throat Engine. It builds a Throat Engine with an interstellar transmitter integrated into its primary structure — aimed outward, designed for coherent propagation across distances consistent with the spacing between nodes.” She traced the emitter’s profile with her stylus. “The construction blueprint includes the machinery for sending the construction blueprint. The array is dark because this node finished propagating long ago. But it’s still here, built into the architecture, because the Engine was never just a wormhole anchor. It was designed as a relay.”
“And the signal carried entangled quantum states,” Nolan said. He could feel it — the shape of the answer, assembling itself from pieces he had been collecting for decades.
Maren nodded. “Half of an entanglement resource, with the other half retained at the launching hub. When the Throat Engine completed bootstrapping, it used those states to open a traversable wormhole back to the origin — the Gao-Jafferis-Wall coupling, negative energy from the quantum tether. And then this node became a launcher itself. New seed signals to more distant targets. New entanglement resources. The network propagating outward.”
“How do you get the entanglement resource to a new location?” Herrera asked.
“You send it at the speed of light,” Maren said. “Carried in the signal. And you wait.”
“For how long?”
“For however long it takes light to cross the distance. Millions of years between stars. Hundreds of millions between galaxies. Billions, to reach the far side of the observable universe.” She said it with the calm of a mathematician stating a theorem. “The builders were patient on scales that make geology look impulsive.”
After the presentation, when the crew had dispersed to process what they’d heard, Adaeze found Maren alone at the observation port, looking at the Throat Engine’s dark bulk silhouetted against the stars. Her tablet was in her lap. Her stylus was still. She was not drawing, not calculating — just looking, with the expression of someone standing inside a building they’d designed from blueprints and finding it exactly the right size and shape and somehow not at all what they’d imagined.
“You predicted all of this,” Adaeze said. “Eight years ago. You should be celebrating.”
Maren was quiet for a moment. “I published the seed signal paper in 2149. It received seventeen citations. Fifteen from researchers who hadn’t read the mathematics, and two from those who had.” She paused. “I gave a conference talk in Oslo and a man in the third row fell asleep during the derivation. I could hear him snoring during the Q&A.”
“And now you’re standing in front of the thing you described.”
“And it’s exactly what I said it would be. Every parameter, every construction principle, every propagation mechanism — confirmed to arbitrary precision.” She turned from the viewport. Her face held something Adaeze hadn’t seen before: not satisfaction, not vindication, but a complicated grief that seemed to have no target. “I keep waiting for the feeling, Adaeze. The one where the world catches up and you get to say I told you so and it fills the hole that was left by all the years of being right in a room by yourself. And it doesn’t come. The hole isn’t there. You just move on to the next thing you can see that no one else can see yet, and you start waiting again.”
Adaeze was quiet for a while, looking at the ancient machinery drifting beyond the glass — structures assembled from starlight and patience by an intelligence that had been right about the universe for eleven billion years, and that had been alone with that rightness for most of it.
“For what it’s worth,” she said, “I read the math.”
“I know,” Maren said. “You were one of the two.”
There was one other observation that accumulated quietly alongside the science. At every node they visited, Yuki detected the same gravitational wave anomaly she had first flagged at the wormhole mouth near Earth — the structured periodicity in the spacetime background, the slow deliberate pulse that matched no natural source. But here, deeper in the network, it was stronger. Not faintly stronger. Categorically stronger, as if the signal had been gathering tributaries at every node, building in complexity and amplitude the way a river builds as it approaches the sea.
“The inner nodes carry more structure,” she told Maren during a late-night analysis session, the two of them alone in the Thread’s sensor bay with the data scrolling across three displays. Outside the viewport, a binary star system cast doubled shadows across the hull, and the silence had the particular quality it took on after midnight — the ship’s systems cycling down to their maintenance register, the corridors empty except for Maren, who had been walking them when she heard Yuki’s humming through the open hatch and followed it in.
“At the outer Capillaries, it was barely distinguishable from noise. Here, at the Trunk Lines, it’s unmistakable. Layered modulations, nested periodicities. And it’s directional — flowing inward.”
Maren studied the waveforms. “A gravitational wave current,” she said. “Carrying information?”
“I don’t know what else to call it. The structure is too organized for anything passive. It looks like data.” Yuki adjusted a filter, her fingers moving with the unconscious fluency of someone whose hands had been speaking to machines longer than her voice had been speaking to people. The lullaby resumed — three notes, a pause, three notes — and she caught herself and stopped. “Sorry. I don’t notice I’m doing it.”
“Don’t stop on my account. I haven’t slept through a full night since I was nine years old. Your humming is the most restful sound on this ship.”
Yuki glanced at her. “Nine?”
“Bergen. The polar dark. My mother used to find me doing mathematics at the kitchen table before dawn. She never told me to go back to bed. She’d just sit with me until the light came.” Maren’s stylus moved in her hand, tracing waveform shapes on the tablet’s margin. “I think she understood that some minds aren’t built for rest. They’re built for this — for sitting in the dark with data, waiting for it to say something.”
Yuki turned back to her displays. The humming resumed, barely audible. “My grandmother used to say that people who can’t sleep are listening for something the rest of the world has decided not to hear.”
“What was she listening for?”
“The rice cooker timer. She was very practical.” Yuki pulled up another filter bank and studied the waveform cascading across the screen. “But I think about it sometimes — the listening. When I was small, I took apart everything in our house. Not to break things. To hear what they were saying. Every machine has a voice if you know how to listen. The gears talk to each other. The circuits carry arguments.” She gestured at the data streaming across the display. “This is a bigger version of the same thing. The universe talking to itself through these wormholes for billions of years, and we’re sitting in a sensor bay at two in the morning, eavesdropping.”
They exchanged a glance — the shared look of two scientists standing at the edge of an implication they were not yet willing to state aloud — and returned to their instruments.
Herrera read Yuki’s anomaly report the next morning — her characterization of the structured periodicity, filed with a half-dozen caveats and the careful honesty that was her signature. He read it twice. He was not a physicist. He did not need to be. A signal directed inward, along the axis of a wormhole network that funneled everything toward the galactic center. A pulse too regular for any known natural process, growing stronger at every node, flowing toward whatever waited at the end of the road they were traveling.
He wrote a single line in his journal that night: Something is listening along this road. He closed the journal, pressed his palm flat on the cover, and stowed it in the drawer with the soft click the crew had come to know. But tonight the ritual felt different, even to him. Less like preparation. More like a lock being tested.
The biology confirmed the topology.
Adaeze catalogued life at every stop, and the gradient she had identified in the Lacework data over the preceding decade held with elegant precision. Inward meant older. Inward meant more complex. The single-celled organisms of the outer galaxy gave way to elaborate microbial communities, then to cells with membrane-bound organelles — the first hints of eukaryotic organization, the kind of internal complexity that on Earth had taken two billion years to evolve. Deeper still, primitive multicellular assemblages: mats of cooperating cells sharing nutrients through channels that weren’t quite tissues but were reaching toward the idea.
On a temperate world three hops from the galactic center, they found something that moved. Filamentous, plant-like structures that grew toward water sources with a purposefulness that suggested rudimentary sensory capability — slow, eyeless, patient organisms following moisture gradients across rock faces over the course of days. Adaeze collected samples with the care of a woman handling irreplaceable things.
“Seeding happened from the inside out,” she told the crew. “Life was delivered to these inner worlds first, billions of years before it reached the outer galaxy. Everything we’re seeing is ordered by time — and time flows outward from the center.”
At the third Trunk Line node, Ren pulled up the full network map and overlaid the topology analysis he had been running throughout the journey. The pattern was absolute: a tree with its root at a gravitationally quiet zone two to three kiloparsecs from Sagittarius A*. Every path they had traced, every Trunk Line they had followed, every converging gradient in biology and infrastructure and age, pointed to the same coordinates.
“That’s where we’re going,” Nolan said.
Twelve hops from Earth. Four months of transit and survey. They reached the center.