There's no answer to the rap of his knuckles, but Alan didn't expect one. He steels himself a final time, with his palm slightly damp with nervous perspiration, slick on the handle, and pushes the door open.

It's brighter in John's room than he expects it to be, all the windows open. John's always seemed as though he belongs in darkness, seems suited to it. His brother's sat himself in the middle of the carpet with his back to the door. Arrayed around him, neatly organized according to some esoteric system, cross referenced into a grid by size and function, are the myriad components of a telescope.

Alan's heart skips a beat with an irrepressible excitement, just at the sight of the thing. It's a shocking jolt of nostalgia, cutting right through the nervousness, for a time when he could never have imagined being hated by his brother.

In between terms at Princeton, John had taken rotations in orbit with their father, building TB5. In between trips into orbit, he'd had a custom training course that their father had commissioned from associates at NASA. In the rare spaces in between all of this, John's downtime had been spent building an amateur Dobsonian telescope, about as tall as he was. Alan had been twelve, that same year of the new bedroom and the morning star through the skylight, when John had let him help build a telescope.

It's a simple enough object, the Dobsonian telescope. A curved mirror gathering light and magnifying it into a focal point, reflected into a secondary mirror and then into a lensed eyepiece. At the heart of it, the heart of all reflecting telescopes, is the primary mirror, curved to gather and focus long ago, distant light. And John could have had Brains' make it for him, custom. Could have ordered it from the sort of company that made these sorts of things-could have ordered the whole telescope, another one to match the caliber of the one he'd gotten as a graduation present.

But he'd decided to grind it by hand.

Alan remembers how Virgil had scoffed, literally pointed and laughed, because it was a seventeenth century solution to a twenty-first century problem, and the sheer inefficiency of it had been deeply offensive to the middle child. Gordon, of course, hadn't cared. All Gordon had cared about back then were his lap times. Scott had been absent, off flying for his mother country before he was due to come home and fly for his father. Alan can't remember if their father had said anything one way or the other. Alan doesn't remember how his father had spent his free time, because it had never really been spent with him. Clearly if John wanted to spend his free time rubbing glass together, that had been all right with their father.

They had angle grinders, they had lathes. They had a basement full of machinery, they could make anything in the world. John had just grinned and shrugged and said if it had been good enough for Dobson almost a century ago, it could be good enough for him. There was something important about doing it by hand.

So those spare hours, down in one of the little beach houses scattered around the island, John tall and lithe and laughing at his tag-along little brother. Alan remembers John with his long fingered hands running a flat lens of glass against another, with an abrasive mixed with water in between, making a slight concavity in the surface, a carefully calculated curve. The scraping rasp of glass on silicate on glass, harsh and unpleasant at first, but eventually as regular and soothing as the waves against the shore.

Alan remembers putting his hands on the circle of glass, what will become the telescope mirror, and letting his brother guide him through the motion of grinding it against the other piece, the tool glass. He remembers John making careful time, curious to know how long it was taking, and how it had been about nine hours, piecemeal, snatched in fifteen and twenty minute sessions after dinner or early in the morning, before the glass had been ready for polishing.

It had been so strange to see the curve of the glass come into being. Each time he felt he'd made progress, John had hauled the round disc of glass out into the sunlight, and had Alan help him measure the focal length-the distance where the light came to its sharpest point. Finally he'd gotten the measurement he'd wanted.

Then there'd been the polishing.

Grinding the glass had been easy, the lubrication of water making the process go quickly. Polishing took effort, took muscle and pressure and John with his sleeves rolled up over leanly muscular forearms had given Alan hope that one day he might be less noodly himself. The polishing had taken forever. John had gotten a fever in him once the raw curve of the mirror was ready, and had woken Alan from a school night's sleep, to traipse down the the beach and keep him company while he worked for three hours straight, until he was satisfied.

John's arms had been sore, he'd been tired, it had been three in the morning. And Alan had offered to carry the heavy disc of glass back up to the house. Brains kept odd hours, there was a decent chance he was still awake, so they could ask him to vacuum coat the polished surface with aluminum and make it into a real mirror. John had assured him that this would be the best part, and even drowsy and sleepless, Alan had been excited.

He would never remember if he'd tripped over something or just stumbled, but it had been on the steps up the cliff face back to the house, and the beautiful, precious piece of glass had gone slipping from his fingers, and shattered into pieces.

And John, in the same moment that his little brother's heart had seized and clenched with awful, horrible guilt, had helped Alan up off his knees, dusted him off, and laughed. Where Alan had expected shouting and disappointment, his brother had only forgiven him, instantly, known it for an accident, and just laughed.

Laughed at the irony of it, of bad luck, of mischance. Laughed at his own impatience, at the fact that he'd dragged his dozy little brother down to the beach to watch something about as interesting as watching paint dry. Of course he wasn't mad. He'd slung an arm around Alan's shoulders, ruffled his hair, and said he'd start again in the morning.

This isn't like that, though.

And this isn't that telescope-Alan doesn't know this one, some mass produced commercial thing. John's taken it apart completely, unscrewed every screw, loosened every piece of housing, detached the mirrors from the inside and laid them out. Alan's not actually sure he intends to put it back together, he seems to have stopped, sat in the middle of all the pieces, quiet.

He spares his little brother from speaking as he picks up a mirror and peers into it, angling it back over his shoulder, the gleam of a green eye in polished silver glass. There's no anger in him now, not like there was the last time Alan crossed the threshold into John's territory. But he sounds tired, resigned when he says, "C'mon in, Alan."

Alan does. He's almost furtive as he crosses the room, sits on the end of the bed. John's set his boundaries in tiny screws and telescope parts, not to be disturbed, and that's fine. Alan needs the edge of the bed to clench his hands in anyway, nervous sweat on his palms and all the words dried out of his mouth. He knows he needs to say he's sorry, to apologize for what he's done, but the words won't come. It's John who speaks first.

He picks up a small glass lens and turns it over and over, his fingertips keeping to the edges, not touching the actual optic. "I need to tell you I'm sorry. I put you through a lot and I took a risk you shouldn't have been part of. I made a mistake, Alan, and if I'd known you were in danger I would have-well, I'd have done things differently. So I'm sorry for that. You did what you did because you were scared. I understand, and I'm sorry I ever put you in that position."

"It's okay," Alan manages, though it's hushed, emotional, and then the words are just falling out of him. "I'm sorry too, John, I'm sorry about Five. I didn't want to do it, I had to. I'm sorry Gordon got in your face about it and I'm sorry nobody knows what to say. I was-we all were-but we were just really scared you were gonna die, Johnny. That thing wanted to kill you. I couldn't let anybody kill you."

This gets another long pause and John's fingers moving over the lens spin it faster, roll it along the pads of his fingertips. "I don't know if it would have come to that. I don't think it would have, but..." he trails off, shrugs. "I won't know, now. It's not just about Five, Alan. It's about EOS, too. I was responsible for her and I let her down. She was new. She was different, she was the first of her kind. I had to give her that last chance to make the right choice. None of you knew enough to trust me to make that call. I've really had to think about it, but I don't blame you."

He continues, and he sounds sorry, sounds impossibly sad, as he says, "I can't thank you, yet, Al. I've thought about it a lot, and I've wanted to and a couple times I've almost tried but-" Words fail John, too, but only for a moment. "I don't know. Someday, I hope. I'd be dead if it weren't for you, Alan, and I do know that. But what it cost-" he shrugs, repeats himself, "I just can't thank you.

"That's okay," Alan answers again, for lack of anything better to say. His hands are still clenched on the edge of the bed, but they're loosening gradually. "I just...it's been a long week, I guess. Are...are we gonna be okay, John? Scott says you don't, but-I mean, how would he know-you don't hate me or anything, right?"

There's no pause, this time, and John actually looks up when he answers, his brow arched in concern, "No, Allie, of course I don't hate you. God, Alan. No. Just-I guess I just need a bit more time. I don't know. I have to think. I've lost a lot and I've never been good with grieving."

That's another thing they have in common, but grief in the family has always been something they all had together. Their mother, their father and the collective mourning of their sons. This is something all John's own, and something he won't be able to share. No wonder he's seemed alone. Alan hadn't thought of it like grieving. "If I can do anything-"

John shakes his head, and Alan deflates a little. But he rallies, determined, because if you let John choose, John will always choose to be alone. So he hesitates and then blurts, "I know you're gonna miss it. Being up in orbit, up on Five. I know I'm not...I'm not really like you, with space and everything, but I always tried to be. And, uh, if...if you want, when you're ready...um. You could come up with me in Thunderbird 3. I mean, I could use a co-pilot. I know you can fly it, you flew it with Dad. I don't go out a lot, but when I do-if you want, I'd like it if you came. Maybe it would help."

This seems like maybe something that hadn't occurred to John and he looks up at his brother, speculative. "Yeah. Maybe. I mean, I'll think about it. I haven't flown 'Three since I was-"

"My age."

Alan almost thinks he imagines a ghost of a grin on his brother's face. "...right. Way to make me feel old, Alan."

Alan grins back, stands up, shrugs. I'm just glad you're gonna get older. He peers at the array of telescope parts on the carpet. "D'you want any help putting that back together?"

John reaches out and picks up the housing of the telescope's disassembled eyepiece. "Oh...uh, no. No, I don't think it's gonna go back together. I got kinda carried away. I mostly just wanted to pull the mirror out of it, maybe polish it, but-" He stops, turns the piece over between his fingers. "Just needed something to do with my hands."

"You should take the primary reflector, put it in a new 'scope." Alan's tentative about the suggestion, but things already seem less icy with John. Still, it's probably time to disengage. "Let me know if you do. I'm, uh, I'm gonna go help Grandma with dinner."

"Okay." John seems as though he wants to say something more, and Alan lingers a moment. "Tell her I'll come down, tonight. She doesn't need to bring me anything, I'll come down. I should stop being such a..." He waves a hand, vaguely, assumes the gesture captures his meaning.

It does and Alan nods. "I'll tell her. See you at dinner, John."

"See you, Al."

It's not that night, nor is it the next one. But the one after that, there's a knock on Alan's door. Alan's sprawled out on his bed, poking indifferently at a simple gem swapping game, trying to get his brain to wind down so he can sleep.

That third night, with his brain full of a long day in Pod A next to Gordon, clearing rubble from the streets of a broken city. The roar of the sea all around the island not quite as soothing as usual-and John's turned up at his door, twenty-seven, tall and taciturn. He's carrying a holographic tablet and he clears his throat.

"First draft of the new schematics for the new station," he explains, gestures awkwardly with the tablet. "I haven't looked yet, but I guess you and I are going to be rebuilding her together. I thought-I mean, probably you're trying to get to bed, Al, I just wanted to know if-if you wanted to have a look."

Alan sits up in bed, shoves the tablet he'd been playing with off to land on the floor with a thud. And he beams at his brother. "Get in here, John," he demands and gets a shy smile in answer as his brother steps across the threshold and closes the door.

And with the shadow of the future between them, blue and bright and hopeful, they talk all night, until the rise of the morning star.