The Frontier's End

"The Frontier's End" is included as prelude No. 18 in *The Juno Contingency (novel)* .

## Teaser

An alien visitor arrives in Earth's system bearing news of an impending catastrophe.

## Plot

### 1. Blunt Contact

In the year 2112, deep space miner Domino Thales is adrift in the Trojan asteroids, broadcasting a distress signal, when a large alien craft suddenly appears before her. She attempts to communicate but receives no response. Suddenly her ship goes completely dead and she finds her reactor has disappeared from inside. She runs her life support off batteries and calculates that she has less than a day to live.

Hours later she is shocked to see a tall humanoid with equine features appear inside her ship. A translated voice speaks for him in several languages until Domino recognizes English, in which they begin to converse. The alien introduces himself as "the Mariner" and says he made his final "thread" to this system looking to refuel. His ship's AI, Noë, recommended exploring this uncharted system because of its anomalous radio emissions, and they apparently homed in on Domino's ship because of its distress signal.

The Mariner says he took Domino's reactor to power his ship's FTL drive. He needs to recharge it with a Gigawatt-scale power source, but Domino's reactor has proved insufficient, and he asks her to guide him to more power sources. Domino objects that he was simply going to let her die if her reactor gave him what he needed, but the Mariner mumbles that it wasn't going to matter anyway. Now he promises to convey her to safety if she can help him find sufficient power.

Domino reluctantly agrees, and the Mariner has Noë "thread" her over to his ship. After a disorienting black flash, she finds herself standing on the Mariner's bridge. The ship has artificial gravity and is a cluttered mess, piled with food supplies, broken machines, and alien gewgaws. Noë appears as a holographic human and engages Domino in conversation. Domino asks Noë where they're from, and Noë shows her a map of her travels with the Mariner since she was born in the W51 nebula, 20 years ago and 17,000 light–years away.

The Mariner shows Domino the hold of his ship where Noë has used nanotechnology to interface her ship's reactor with their FTL drive. He explains the drive is of alien manufacture and its inner workings are unknown to both him and Noë, just that it uses an artificial singularity to fold space, but its singularity is currently too weak to power another interstellar thread. They usually rely on solar power to charge it slowly, but there isn't enough time out here in the Trojan asteroids. Domino describes how her ship was raided by pirates and suggests that the Mariner can rob those ships of their reactors as he did hers.

### 2. "Remember Me?"

Using Noë's scans of the Trojans, Domino is able to single out the pirate ship that raided hers. Noë plots a short thread to it, and Domino experiences the transit as the universe melting through a fisheye perspective then lurching through a jarring discontinuity. They appear behind the pirate ship and surprise it, but it launches missiles at them. Domino watches Noë easily disable the missiles, then isolate the ship's reactor and use their thread drive to extract it from the ship—as they did with hers. With the ship neutralized, Domino taunts the stranded pirates over her emergency radio.

Down in the engine room they assimilate the other ship's room-sized reactor. Their range is extended but not enough for an interstellar thread, and the Mariner remarks that they're running out of time. Domino suggests they can go to the pirates' home base, which should have a 10-Megawatt reactor. The Mariner is shocked at her description of a reactor with dozens of tons of enriched uranium, as uranium is a scarce element on most planets he's visited. Domino remarks that her home planet has an abundance of it, where they mine it by the hundreds of thousands of tons. The Mariner wonders what vessels his people could have built with such a power source.

The Mariner threads his ship into the vicinity of the pirate base and they hide behind an asteroid. Noë's remote sensors build an internal blueprint of the base, then she threads the Mariner directly onto the vessel. Domino watches in horror as he brutally fights his way through the pirates. Whenever he gets cornered, Noë continually threads him around to escape and surprise his attackers. At the end of the raid he isolates the base's large reactor and Noë transports them back.

Domino is shocked at his blood-stained appearance, but the Mariner doesn't understand her reaction, as she was happy that they left the last pirates behind to die. Domino tries to explain that there's a difference between treating the other pirates the way they treated her, and brutally killing a bunch of different people. Even Noë counters that this argument doesn't make logical sense. The Mariner apologizes for taking things too far, but he again grumbles that the pirates were going to die sooner or later no matter what.

The three stolen reactors now take up the rest of the Mariner's engine room, and provide them the range to thread to Jupiter, but it would still take two weeks to charge up for interstellar travel. The Mariner insists they need to get moving right away and asks Domino to guide them to a bigger power source around Jupiter. Domino refuses to cooperate further unless he tells her what's really going on.

### 3. Stellarlysis

The Mariner relents and decides to tell her the truth. Twenty years ago, other threadships appeared in his home system and warned of a cascading effect sweeping down their arm of the galaxy. It propagates faster than light and causes stars to rupture in a process called "stellarlysis." It inhibits gravitational attraction so that stars lose the pressure to produce nuclear fusion, causing them to gradually diffuse into a giant gas cloud. It has never been observed what causes the effect, but it appears to be hopping from star to star in a chain reaction. The predominant theory is that it's a weapon used in a war between Kardashev III–level civilizations that is obliterating the Milky Way, traveling from the Galactic Core outwards.

The Mariner says he's traveled to many worlds since then and none has been able to stop the effect. The only solution is to run from it towards the Galactic Rim. He and Noë have been hopping from star to star, recharging their thread drive with solar energy ever since. He was only 5 parsecs ahead of the effect before his last thread brought him to Domino's ship, and with the time they've already spent here they have only two days to get moving again.

As he recants his tale, Domino looks out the window and realizes with horror that every star she is looking at is probably gone already. The ghost images of the stars will continue propagating for millennia, but the galaxy itself is dead.

Domino asks why he didn't tell her the truth right away so that they could save more people. He says all threaders go through a "savior" phase where they try to convince people to flee, but no government ever listens, and at best only a few will flee, so he's since stopped trying. Domino realizes that, with the speeds his ship can travel, he should have arrived at the Rim years ago. She deduces that he's straggling behind, either to help people or to look for someone, and that he's not as jaded as he wishes to appear. The Mariner admits she's right: he lost contact with the others in his caravan a decade ago and has been examining uncharted but promising planets ever since, hoping to reconnect with them.

Now that he's told her the truth, he offers to take Domino with him when he flees the system, so long as she helps him find sufficient power. Domino says it isn't much of a deal to make her the universe's last surviving Homo sapiens. She will help him escape, but he has to pay a much higher price.

### 4. The Visegrád

Domino tells the Mariner about a colony ship that she spent a year training to be on, only to miss the cutoff for the final mission. The ship is much larger and better-stocked than the Mariner's as it will support a crew of sixty for years. It's powered by a large nuclear reactor that is too big to fit in the Mariner's ship, but, if he can transfer his thread drive over to that ship and bring its people along, then she will tell him everything he needs to know. The Mariner attempts to find the ship just from her description in Noë's scans but is unable to. Noë assures him that they can thread a larger ship with only logarithmically more energy, and that it would be a wise investment to have such a powerful reactor core at their disposal.

The Mariner is chagrined but agrees. Domino gives him the details on the colony ship, the Visegrád, that is heading for Jupiter's ice moon Europa. It has a Gigascale nuclear core in order to heat and terraform the planet's ice oceans. Domino gives him the ship's approximate coordinates, and Noë executes a final thread to appear abreast of the ship.

The crew of the Visegrád is stunned to see the extraterrestrial ship and also their former crewmate, Domino, in the company of an alien. They convene a meeting on the Visegrád where Domino meets with her former leader, Captain Styles, and the bridge crew. Domino explains her encounters with the Mariner, and he and Noë give an account of the stellarlytic effect and why they must flee. The crew is suspicious but is willing to barter with the alien.

Captain Styles proposes that they couple their ship with the Mariner's, if only to utilize and learn from its advanced thread drive. If the Mariner can prove to them that stellarlysis is real and that the Solar system is doomed, only then will they decide to flee. The colonists aboard are mostly complete families who wouldn't be leaving much on Earth behind, so they are one of the only ships that could easily depart.

Styles is suspicious of the Mariner, however, and asks why he would suddenly change his ways and help them, and how they can trust him not to abandon them after they've made their escape. The Mariner explains that he's simply been doing this alone for too long, and at some point pure survival is no longer enough. Working with Domino has convinced him that it would be nice to have a crew again. Styles says that he's satisfied for now, and he puts the proposal to the crew, which votes to proceed.

*Read the conclusion "5. Fire Sale" on Amazon.*