Jack has breathed Space Shuttle air, its scents of plastics, disinfectant, human sweat.

He knows what space smells like - knows the burnt-toast smell of hard vacuum.

This room – this ship - smells like nothing he has words for.

There is an odd, rich staleness to the air, as if in being recycled too many times it has acquired residues from too many lungs. There is a sweetness to it, and a sharpness, that suggest nothing natural – nothing that he thinks of as natural. Laced with these qualities is a more alien one: warm and alive, an exudation of the matte-gold walls and the warm floors, or simply a by-product of the air recycling process.

Six hundred miles below Jack's feet, humanity is reeling with the revelation that it is not alone in the universe, and maybe so will he, when it all sinks in.

For the moment, this oddly shaped, odd-smelling chamber means more than the worldview-shattering event of mankind's first contact with extraterrestrial life.

John is alive.

Four years ago, Jack had stood in another room filled with traces of his son's life, every piece of clothing, every book, every record or CD catching at his memory. Jack, old astronaut that he was, didn't need to see a body to understand that his child was dead. There were too many ways of dying out there – asphyxiation, freezing, a micro-collision, the explosion of the Farscape-1's small store of fuel – too many ways of dying, and not a single way he could imagine that John could live.

Yet here Jack is: standing in his son's quarters aboard the spaceship where John has made his home, all these years that Jack thought him dead.

Shame wells up suddenly but he tamps down on it. It's not rational.

Doubts that crowded him in the weeks since the first radio contact with John's companions fall away now at the material evidence of his son's life. He has seen the module in the hangar bay, its designation, 'United States of America', almost unreadable under the dirt of four years in outer space. Dents, smudges, and scratches told stories of close scrapes Jack doesn't want to imagine. The way the little ship sat in the vast hangar like it belonged there disconcerts him. Bits of alien technology jutted from its mangled surface with utter conviction. Yet it was the module's hybridization that drove home the fact that his son lives. Each unidentifiable new component declared John's tinkering presence.

The room he faces now offers less reassurance. Silent, its walls made entirely of oddly-shaped recesses, it is sparsely equipped with furniture, all of which seems subtly unfit to accommodate human bodies. The latticed door betrays an alien idea of privacy, or perhaps minds to whom the very idea of privacy is alien. The sloping bed looks grown rather than built, as does the vaguely triangular table that is accompanied by a single stool echoing its shape. A variety of undefinable odds and ends sits on a low shelf behind the table. The battered FS-1 flight bag placed beside them is the only thing that Jack can connect to John.

He moves into the strange space, hesitantly. Hidden corners come into view as he progresses deeper into the dimness. Some neatly folded clothes – t-shirts, or something very similar, all of them black – on a shelf. A battered leather jacket on a peg on the wall. Jack tries to imagine John wearing it; can't. The John he remembers was fond of soft flannel. He feels a sudden desire to touch the clothes, smell them to find his son's scent – registers with a detached, amazed amusement that a primitive part of his brain has all but taken over, looking for the most fundamental reassurance.

The alien waiting behind him breathes in an inhuman rhythm, the pauses between breaths just slightly too long.

He reaches out to touch the jacket; stops himself.

"You don't believe these are your son's quarters," the alien observes, her English flawless, yet ever so slightly off, like her breathing. Her tone is neutral, not judging him for his distrust.

He finds no reply.

He remembers the day they officially gave up hope of finding John's remains. His survival was impossible by then: even if he had survived the magnetic wave he would have run out of air eventually. Jack remembers how the tension that had kept him going for days was replaced by an endless tiredness, an almost-relief.

He remembers the funeral that wasn't a funeral, the vague sense of gratefulness that Leslie hadn't lived to see it.

Friends told him, afterwards, that a moving, even lyrical speech had been made, by someone high up the food chain - evoking the origin of all life on Earth from the stars, the oneness of humankind with the universe.

Jack didn't remember anyone speaking.

For months, in his nightmares, he saw John dying slowly, alone, over and over, in empty space.

He conditioned himself to believe that there must have been an explosion. The nightmares grew less frequent.

All the while, John had been alive.

A sudden weakness comes, shakes him. He brings his hands to his face, steps back until he feels the edge of the bed against the back of his legs, and sits on it heavily.

Leather squeaking: the alien is approaching him. When he takes his hands from his face she stands looking down at him with an expression between calm curiosity and concern in her intensely green eyes.

"You are distressed," she observes. She hesitates, then adds, "Do you wish to be alone?"

He makes no reply.

"A DRD could show you the way back, later." She sounds as if the very idea of tact, like the language she is using, is strange to her, a new concept she is testing for the first time.

He considers it. Her odd movements and breathing make him almost viscerally uneasy, but even more terrifying is the idea of being on his own in the cavernous spaces of the ship, without another living being – no: the ship is alive – without another being he can talk to, who can talk back.

"When will he be back?" he asks. His voice, perhaps, rougher than he meant it to be.

"I told you; we don't know," she says, very calmly. There is a trace of annoyance at the back of the calm.

He turns his face away, unable to bear her inquisitive eyes.

"Why don't you... take a closer look? At his possessions?" she asks. "It might ease your doubts."

"I don't doubt that he's alive. That he's been here." It sounds angry, almost furious. He tries to calm his voice. "I believe you."

She watches him, and he can't read her face at all.

"I believe you," he repeats, perhaps to reassure himself. "It's not that. It's..." He stares at the floor that is bronze-and-brown, mottled like animal skin; at the ribs protruding from the walls, the lattices behind the ribs, the strange light fixtures. What little light there is always comes from behind things, warm but low and diffuse. The dimensions of the room are difficult to guess; deep shadows dim the corners, make the organic lines all the more unpredictable.

Every place John ever lived in on Earth had been bright, full of straight lines and right angles, white paint on the walls.

Jack lets his gaze wander again over the shelf that holds John's personal belongings. When he comes to the flight bag, he stops – looks back at the item just to the left of it. Strange materials mask a surprising familiarity.

"A chessboard?"

He gets up to examine it. Every piece is clearly handmade, though Jack doesn't recognise the materials. It all looks very technical. Repurposed machine parts of some sort? He picks up the white king, sees it has been put together meticulously from carefully fitted parts in which he sees his son's thoroughness, his dexterity, his patience.

"This is rocket science", John would say when Jack visited the hangar during Farscape-1's creation, and found him putting an ever-finer finish on the carbon hull. The engineering crew would cluck their tongues; he wasn't supposed to be quite so hands-on about the ship's construction, even if he was one of its designers.

"Would you like to play?" says the alien.

Sikozu, he reminds himself. She has a name.

"You know how?" he asks.

"Of course. It isn't difficult." Confidence, bordering on arrogance. It feels more natural in her than her attempt at politeness.

Jack laughs. "That is... not a statement many humans would agree with."

"Crichton told us that he is considered of unusual intelligence, by human standards. A claim we found hard to believe. How could you achieve even rudimentary space travel, if most of you are…" She trails off, suddenly rediscovering tact, perhaps.

Jack laughs again, uneasily. Royal we? he wonders. Or is everybody on this ship a brainiac? … Everybody in the galaxy? He pictures it: a galaxy of intelligent life, no: brilliant life, perhaps as far above humans in intellect as humans are above orang-utans - building, no, growing spaceships, exploring, trading. He considers: fighting? Conquering? Or is that something only blood-thirsty half-apes do?

He gives her an appraising glance, can't read anything of relevance out of her style of dress, her body language.

A galaxy of mensa members; and humans, the cosmic village idiots.

He feels the stab of a familiar sense of inadequacy, quells it as he always has whenever it rose in him as his son soared from peak to peak in school and college. It has always been silly. He is proud of John, always has been, and what does it matter that the boy's brilliance sometimes makes him feel like a Neanderthal? A father can't hope for a greater achievement than a child who outshines him.

He laughs, now, at his own absurdity. He hasn't even met his son again, and here he is, nursing old complexes. Some things, apparently, haven't changed.

Sudden, overwhelming joy: John is alive.

He never did fare too badly against John at chess, did he?

He turns to the alien.

Sikozu. Sikozu. It does kind of roll off the tongue, doesn't it?

He smiles at her.

"Yes. Yes, why not. Let's have a game. While we wait."