Solstice

Ruffin reached down, pushed a button, and the two other members of the Shuttle crew came up in windows beside him. 'In case you forgot, my name is Bill Ruffin. Four missions, two as a commander.'

He pointed to a stoic-looking, thickset black guy with a shining bald head. 'This is David Sampson. Three missions too. Best Shuttle pilot we got on the planet right now, present company included. And this…'

The third was a woman, dressed like the rest of them in standard NASA ground uniform. She wore close-cropped blonde hair and had a thin, intense, impatient face that kept looking at you as if to say: And then? 'Mary Gallagher. Four missions. Just as many EVAs. Do we know what we're in for? I guess not. But… hell, Mary, you tell the guy.'

The woman leaned into the camera and said, 'Professor, we put this damn thing there. If anyone gets the right to turn the off switch, it's us. Okay?'

'Not to mention the fact,' Ruffin added, 'that we also happen to be the best-qualified people around for the job.'

'Agreed, agreed,' Lieberman said. 'Look, I know when I'm beaten. I just want you to understand this isn't exact science. I'm making this up as I go along, so if you people see some holes in it, then holler.'

The three heads nodded above their white uniforms and he knew that, at least, was going to happen.

'The problem,' Lieberman continued, 'is simple. We need to turn Sundog off without touching her, and that, I have to tell you, isn't easy. I assume, Irwin, you still hold to the view there is no way we can get back into the control system directly and do something from earth?'

'Not that I can see right now,' Schulz said on the link from La Finca. 'Charley has that tight in her hot little hand and isn't letting go.'

'In that case, we really have only one option. We need to turn off the sun. We need to starve Sundog of what makes her work, wait for her to run down first into sleep, then into shutdown. Then, if I understand the system right, you guys can get your tool belts out and go to work on her.'

Bill Ruffin smiled and said, 'Neat idea, Professor. How do you propose to do that? My information was that thing's burning brighter than ever right now.'

'Shades. You just get out your sewing kit and start making some shades.'

He'd stared at the model in the command centre for almost an hour trying to work it out beforehand, and still he couldn't spot a flaw in the idea. The part of Sundog he knew best, when he saw a physical representation of it, was almost exactly as he remembered. The satellite hung in space powered by four giant black solar panels on the sun-facing side, with most of the active gear pointed down toward earth. It looked like a huge metallic windmill slowly cartwheeling through the sky, and all you need do — all? — was work out the measure of the dance and move into two-step with it.

'Sundog runs off four solar wings, each a hundred metres long and twenty wide. Now, you people don't need to worry about how much energy that generates or what kind of technology sits in those wings. All you need to know is this: It's big and fast and it's optimized to suck out every last jumping joule out of whatever sunlight falls upon it. And the other side of that equation is that it has no latency. If, for some reason, the light fails — and Sundog was predicated on the idea that this couldn't happen, of course — this little beast assumes it's got big internal problems and starts to turn itself off. So what we do, is this…'

He pressed a button and the badly drawn graphic came up on the screen. 'Shades, four of them, a little oversized compared to the wings themselves, with a central hub so that they maintain the same ratio to each other as the wings. Your engineers can figure out the best way to pack all this into something you can get into the Shuttle. You need some kind of light-absorbing or — reflecting fabric and a means to erect all this in situ. I thought maybe some kind of gas system, like they use to inflate tents. Or poles, whatever.'

Ruffin looked at the image on the screen and said, 'I get the idea. This is just like erecting some big kind of cover for the wings, except that we put them back from the panels and cast them in darkness.'

'Precisely. So we get that in place, we manoeuvre it over the wings, we synchronize it with whatever movement there is — you can do that by hand. And we wait.'

'Won't kill all the light,' Mary Gallagher said. 'There's bound to be some ambient illumination getting around.'

Schulz chipped in, and Lieberman simply adored the enthusiasm in his voice. 'Doesn't matter. Like Michael said, this is a high-performance system. If it's getting anything less than fifty per cent of what it expects, it can't function properly, it goes straight into the sleep sequence. You can hold that frame a couple of metres off the wings themselves and it's still going to kill the thing. And quickly too. Maybe fifteen minutes to sleep. Another fifteen to shutdown.'

Ruffin looked at Lieberman. 'Surely the wings on the satellite can angle themselves. They're supposed to tune to the best source of light they can find. As soon as we move the shades in place, they'll just start shifting Sundog around trying to dodge it, and that could make things real awkward for us.'

'That's why you need the hub,' he said. 'If you tried to do this one shade at a time, that's precisely what would happen. You'd be chasing the thing all over the place, and the three other panels would continue to power it while it tries to improve the angle. Doing it my way, we assemble all four shades together out of sync with the wings, forty-five degrees around from their position. Then turn them into the blackout position all in one go when we're ready. Just like lining up a couple of kid's windmills. Sundog goes from perfect sun to near-total darkness in a second or so and there's nothing in her code that tells her this can be anything but some kind of system failure.'

'Smart.' Ruffin nodded. 'Shame you can't be there to watch it.'

'Yeah, thanks. Actually, I do want to watch it. Can you put cameras in or something?'

'We can relay from Arcadia,' David Sampson said. 'And I can put out a floatcam to sit alongside you and feed back live video. If that doesn't trigger something, of course.'

'No problem with radio or video,' Schulz confirmed. 'I just don't want you using any powered tools in the vicinity, and you're going to have to cut everything but the bare essentials on the Shuttle while you're close.'

'Interesting…' Sampson said.

Lieberman watched the three astronauts. Something was going on between them that they weren't about to share at large.

'How much time will that give you? Drifting in like that?' he asked.

'I need to work that out,' Sampson said. 'I can't match the exact trajectory of Sundog without using some power, of course, but if I come in slow I can get damn close. Provided we make sure we've got long lines out there to these two guys, we can reel them in nice and clean after maybe forty-five minutes or so, with some room to spare.'

'That's enough for us,' Ruffin said, and Mary Gallagher nodded in agreement by his side. 'Let's take this part as read and let the engineers get on with the details. Once we have the system shut down, where do we go from there?'

Schulz took over the graphics feed on the conference and zoomed in on the side of the satellite. 'There's an access panel here. We'll upload all of this so you have it with you, of course. You need an anti-torque driver to get in there, then a smart card and an access code. Once you're there, it's a simple shutdown sequence to take Sundog off-line altogether. And then we're done.'

Lieberman waited for someone to say it. 'Not quite,' he added, when the line stayed silent for longer than he could bear. 'There's one massive solar storm going on up there right now, Irwin. Ordinarily you wouldn't dream of launching a Shuttle into all that crap.'