‘Quite right.’ Earthshine gestured. ‘The floor divides the tunnel in two. Below there is a bay for power, cabling, and life-support systems. And above, memory store and processing capacity. This is an environment designed to survive alone without external support for an extended period. Just like a dome on your Chinese Mars, Jiang Youwei.’

‘This is you,’ Penny said. ‘This computer facility. You are stored here. We’re walking through your head!’

Earthshine laughed – a distracted laugh, but a laugh. ‘It is difficult to be definitive; it is difficult to say what is “me”. Thanks to neutrino links my separated stores around the world are connected by lightspeed comms, but even so there are perceptible delays, a fraction of a second. As if parts of my head are slower to respond. But, yes, I intend this to be my primary node for the moment.’

‘Because you think you’ll be safe here,’ King said. ‘Under the English Channel?’

And suddenly Penny realised where she was.

‘That’s the idea,’ Earthshine said. ‘This is the old Angleterre-France tunnel, or one of them; you reached it via an upgrade of a relatively recently built subway. We’re not, in fact, under the Channel; we’re not as far out as that. The tunnels were abandoned as transport links when the first cross-Channel monorail bridges were opened. But they are built of centuries-old concrete and are as tough as they come – in fact more than ever, after a dusting of nanotech. An ideal refuge. Besides, something in me likes the idea that I am inhabiting a ruin, with a historic purpose of its own. My siblings, you know, prefer to dig out their own custom-designed bunkers. Perhaps this is all an expression of my own link back to humanity, however tenuous it might seem to you, which is where I differ from my fellows.’

King grunted. ‘Taking no chances, are you?’

‘Would you?’

‘Well, I’m impressed,’ Penny said.

‘Thank you, Colonel Kalinski.’

They had been walking more and more quickly, driven by the sense of urgency that emanated from Earthshine. Jiang was getting breathless. Penny went to take his arm, but he shook his head.

Earthshine cut to the left, and they followed him into a side chamber. Though a mere offshoot of the main tunnel, this was a big space itself, with walls of brick, heavily painted a faded yellow colour. There was a scattering of chairs, tables, slates, doors that led through partition walls to what looked like bedrooms. Maybe this had once been an equipment store, Penny thought, a control room, or a fire-control position.

But today the room was dominated by tremendous screens, plastered over each wall and free-standing on the floor, screens filled with images beamed from space, trajectory graphs, talking heads on conventional news channels. There were no staff here, no interpreters, no analysts. Just the screens, bringing a flood of data into this place.

The group spread out, the security guys pulling up chairs to sit against one wall. Jiang sat too, heavily, with a sigh of relief. A servo-robot, a squat cylinder like a dustbin, rolled towards them bearing a tray of coffees, glasses of wine, water, orange juice. Earthshine reached down and took a coffee, evidently a virtual placed among the real versions, an impressive bit of realisation in Penny’s eyes.

Earthshine said, ‘All this data flows through me, gathered from every source to which I and my siblings have access. Call it nostalgia. I feel that today, of all days, I want to experience what is to come as human, through human eyes, at a human pace, as far as possible.’

Penny nodded. ‘But a human with a very large disposable budget for TV screens.’

‘There is that.’

King was still standing, leaning on his stick under one of the larger screens. ‘Look at that. Jesus.’

It was an image taken from some spaceborne telescope, Penny saw. She recognised the curve of the Earth, just a sliver of it, in the corner; the stars were washed out by the brightness. But there was the Splinter, brilliantly sunlit, and sparkling – no, she saw as the imager zoomed in, the rock was breaking up.

‘Calving,’ Jiang Youwei said.

King turned on him. ‘All part of your master plan, is it?’

‘I am privy to no plan.’

‘I told you there had been developments,’ Earthshine said. ‘It only just started. And it’s certainly deliberate. Some of the ground-based ’scopes have been observing explosions, detonations in the structure of the asteroid. A couple of fragments have been slung away, but the rest, as a swarm now, are still heading for Earth. You don’t get a sense of scale from these images. The object, or the swarm, is still heading for Earth at interplanetary speeds. It is still far away, but—’

‘Closing all the time,’ King said.

‘Yes. The old estimates of close-encounter time are defunct, by the way. Given the scatter of the object – well, the encounter has already begun. There is news from other theatres,’ Earthshine said now.

King turned on him. ‘Theatres? What kind of a word is that?’

‘Is it not appropriate? Is this not a war?’

‘Just tell us,’ Penny said.

Earthshine pointed to various displays. ‘At the asteroids, and over Mars, UN hulk ships have appeared.’

‘Appeared?’ King snapped, again showing his tension. ‘What do you mean, appeared?’

‘They seem to have been hidden until now by some kind of stealth technology.’

‘It’s hard to imagine how a kernel-physics drive in operation could be cloaked,’ Penny said. ‘They must have been in place for a while.’

‘This is the UN response to the Sliver,’ said King. ‘Or part of it. All part of the game. The targets are obvious, I guess, and symbolic: the Halls of Ceres, the Obelisk on Mars.’

‘But this is all just sabre-rattling, right?’ Penny said. ‘Nobody’s fighting yet. Nobody’s dying.’

‘Not quite true,’ Jiang said, and he pointed to an image of a riot somewhere on Earth, a crowd running at a line of tanks.

Earthshine said, ‘The war in heaven is already starting to cast shadows on Earth. There are reports of clashes at Chinese borders with UN nations. In Siberia, for instance. And in Australia, there is a rebellion going on in Melbourne against Chinese rule. The Splinter has not been wielded in their name, they protest.’

‘Too right,’ Sir Michael King said, his own Australian accent thickening. ‘Let’s kick those Red Chinese back into the sea . . .’

At least he had his home to think of, Penny reflected. She herself was rootless; she had no home worth recollecting. Only Stef.

And she wondered where her twin was, right now. It was an eerie thought that whatever happened today, it would take Stef four years to learn about it. She’d had only one message from Stef, in fact, since she’d gone through the Hatch on Mercury, a simple confirmation that she and Yuri Eden had survived the passage. Penny had made screen-grabs from the message, scratchy, frozen images of Stef’s face. The face of a woman who had just survived an experience she could barely describe, let alone understand. And there she was on a whole new world, a world awaiting her discovery.

Did Penny envy her? Maybe. But mostly, like right now, she wanted her sister back. Not just physically, not just from across this thick barrier of spacetime that separated them. Back the way it had been before the two of them (as she recalled it) had opened that damn Hatch on Mercury. And –

‘This is it,’ called King.

CHAPTER 73

Stef Kalinski had been able to acquire maps of the dark side of Per Ardua from the ISF authorities at the Hub base. She spread them out on the floor of the garage Yuri had built to house the ColU, outside his villa on the outskirts of the UN enclave, so all four members of the expedition could see them: Stef herself, Yuri, Liu Tao and the ColU. Yuri had never known such maps even existed; he’d always assumed the dark side was just a blank mystery.