Chapter 2: Green World
Table of Contents
Two years later, humanity went through.
Nolan Cade watched from the ground. The wormhole had made him the most recognized name on Earth — the amateur astronomer who found the door at the edge of the solar system. It had also ended his spacefaring career before it began. Commander Vasik’s mission report, filed with the United Nations Office of Extrasolar Affairs, documented his deception in precise, clinical detail: a civilian passenger who manipulated his way aboard a government science mission under false pretenses, withheld material information affecting mission planning, and compromised crew cohesion during a long-duration deep-space operation. The report recommended that no future mission accept him in any capacity.
The recommendation was adopted.
He was famous, and he was grounded, and he spent the two years between discovery and transit at his ranch in Wyoming, watching other people prepare to walk through the door he had found.
The ship that made the first transit was the Meridian — purpose-built at the Ceres shipyards with a hull geometry reinforced against tidal stresses the Perspicacity had never been designed to handle. It carried a crew of twelve, provisions for eighteen months of independent operation, and Dr. Adaeze Obi.
Adaeze had not spent her career preparing for this moment. She had spent it preparing for the question this moment would answer.
As an exobiologist at the University of Nairobi’s astrobiology program, she had built her reputation on a hypothesis that most of her colleagues considered elegant, testable, and almost certainly wrong: that life on Earth had not arisen independently but had been delivered. Seeded by autonomous packages carrying prebiotic chemistry kits — shielded micro-capsules, water-activated, scattered across the galaxy like spores by a civilization old enough to think on evolutionary timescales.
The idea was not new. Crick and Orgel had proposed directed panspermia in 1973. What was new was Adaeze’s detection framework: a rigorous, falsifiable suite of predictions that could distinguish deliberate seeding from independent origins — predictions that could be tested the moment anyone found life on another world.
She had spent years looking for that test closer to home. Anomalous organics in Gale Crater on Mars — long-chain alkanes in ancient mudstone at abundances no known abiotic process could produce. Degradation products consistent with biological membrane synthesis. An ancient standing lake that was precisely the environment where water-activated seed capsules would bloom. None of it was proof. All of it was consistent. And Adaeze had learned to live in the space between those two statements — to carry a hypothesis she believed in her bones was correct and defend it with the scrupulous caution of a scientist who refused to overstate her data.
When the wormhole was confirmed, she felt something that preceded logic: if there was life on the other side, the framework could finally be tested. Not inferred from degradation products billions of years old, but tested directly, on living cells.
She had not slept well in two years.
Transit took eleven seconds.
Eleven seconds of the hull groaning, of instruments losing reference, of the stars outside going from points to smears to a kaleidoscopic tunnel of frame-dragged light, and then — silence. Stillness. A different sky.
They emerged in a system with a single G-type star, warm and steady, burning with the patient luminosity of a middle-aged sun. Five planets, the third in the habitable zone at 0.9 AU. The navigation team confirmed their position through pulsar timing: forty-two thousand light-years from Earth, in a region of the Milky Way’s outer halo that no telescope had ever resolved to individual stars.
Forty-two thousand light-years. In eleven seconds.
But it was the third planet that commanded their attention. Slightly smaller than Earth, wrapped in a pale blue-green atmosphere rich in nitrogen and carbon dioxide with traces of oxygen — not enough for an animal to breathe, but enough.
“Oxygen at two percent is not equilibrium for a dead world,” Adaeze said. Her voice was steady. Her hands were not. “Something is producing it. The ozone layer, the methane-oxygen disequilibrium — this is a biosignature. A weak one. Early-stage. Like Earth three billion years ago.”
They named the planet Viridis, for the faint green tinge of its shallow seas. They achieved orbit in six days. A world in the slow morning of life: continents of bare rock veined with river systems, oceans tinged with pigment, no forests, no movement visible from orbit. But the chemistry was unmistakable.
Adaeze led the sampling mission, descending in the Meridian’s lander to a tidal flat where a shallow sea met a basaltic shore. She collected water, sediment, and scrapings from rocks near the waterline where a faint biofilm left dark stains on the stone.
Under the microscope, she found them. Simple, prokaryotic, membrane-bound cells, dividing slowly in the sample vial. She stained them, imaged them, and ran the molecular analysis suite that had been designed to characterize Kuiper Belt organics and was now, forty-two thousand light-years from the Kuiper Belt, doing what it had always truly been meant to do.
Her hands had stopped shaking. Something deeper than excitement had taken over — the calm of a person watching a prediction become data, one measurement at a time.
“Lipid bilayer membranes,” she reported. “Fatty acid-based. Long-chain, even-carbon-number dominant — C14, C16, C18.” She looked up from the readout. “If life arises independently, there’s no reason for it to build its membranes the same way. Any number of lipid architectures could work. But if life was seeded from a common chemistry kit, the membrane chemistry would be constrained — the same even-carbon bias, driven by the same two-carbon addition pathway. It’s the most efficient route to functional membranes.” She paused. “This is the same bias we see on Earth.”
No one spoke.
“Chirality,” she continued. “Left-handed amino acids. Right-handed sugars.” She set the readout down. “Same as Earth. Independently evolved life could be right-handed, left-handed, or mixed. The odds of two worlds arriving at the same handedness by chance are not impossible, but they’re not good.”
She ran the deeper analysis. The electron transport chains. The nucleotide-like information polymers. The core metabolic architecture — not identical to Earth’s, not after billions of years of independent evolution, but cognate. The same deep logic expressed in different surface grammar. Like sonnets written in different languages — the words were foreign, but the structure rhymed.
She looked up from the microscope at the Meridian’s science team, who had gathered behind her in silence.
“This life didn’t arise independently,” she said. “It came from the same source as Earth life. The same starter kit. Everything on the surface is different — these organisms look nothing like anything on Earth. But the molecular foundation is the same. Everywhere you dig down to bedrock, you find the same chemistry. That doesn’t happen by accident. That happens because someone designed it that way.”
The room erupted. Adaeze sat at her microscope, staring at organisms that confirmed the hypothesis she had spent her career defending, on a world forty-two thousand light-years from the Martian mudstone where the first clue had been preserved in ancient clay, and felt something beyond triumph. Recognition. She had been right about the what. What she hadn’t anticipated was the how.
The implications took days to absorb, argued over in the Meridian’s galley while the analysis suite worked through sample after sample. Every result confirmed the initial finding: Viridian life shared deep biochemical homologies with terrestrial life far beyond what convergent evolution could plausibly produce, but had diverged enormously at every level above the molecular foundation.
“Someone seeded both worlds,” Adaeze said. “Not with organisms — with a chemistry kit. Precursor molecules, catalytic mineral surfaces, lipid vesicle components designed so that when they hit liquid water within the right temperature and pH range, they spontaneously generate populations of self-replicating molecular systems. Darwinian evolution takes over from there. The specific organisms are unpredictable, but the deep chemistry is constrained because it all came from the same recipe.”
“Seed packages,” said the mission’s quantum physicist, turning the idea over. “Water-activated. Passive environmental gating. Billions of them, scattered across the galaxy…”
“But that doesn’t explain the wormhole,” said the astrophysicist. “You don’t need a wormhole to scatter biology. You launch your seed packages at a fraction of c and wait.”
“No,” Adaeze said slowly. The answer had been assembling itself in her mind since Viridis’s biosignature first appeared on the spectrometer, with the quiet inevitability of a proof. “The wormhole and the seeds aren’t separate projects. Think about it — the wormhole doesn’t connect to a random star. It connects to this system, with this habitable world, with this life on it. That’s not coincidence. Whatever built the wormhole also delivered the seeds. The bridge and the garden are one thing.”
She let that settle.
“Think about what that implies. An intelligence that builds wormholes to the worlds it seeds. Not as an afterthought — as part of the same act. The connection and the planting, woven together from the start.” She looked at each of them. “We have no idea how long this has been happening, or how far it reaches. We found one door. But if the pattern holds — if every seed comes with a bridge — the scope of this is something we can’t even begin to estimate from a single data point.”
Silence held the galley for a long moment.
“Then whoever built the wormhole at ninety-seven AU,” the astrophysicist said, “didn’t build just one.”
“No,” Adaeze said. “If the logic holds — if the purpose is to connect seeded worlds — there should be a network. And if there’s a network, there should be more wormholes, waiting to be found.”
The astrophysicist was quiet for a moment. “And if the bridges connect what grows from the seeds,” he said, “what happens when what grows isn’t friendly?”
The question hung in the galley air. Adaeze opened her mouth, closed it. The celebration had been so total, the confirmation so clean, that no one had yet turned the logic over to look at its underside. Bridges don’t choose who crosses them.
“One thing at a time,” the mission commander said, and the conversation moved on. But Adaeze noticed that the astrophysicist did not ask the question again, and did not stop thinking about it either. She could see it in his face for the rest of the voyage home — the look of a man carrying a thought he wished he hadn’t had.