'Now you've really lost it,' Gallinule said. 'In orbit? Inside a planet?'
Merlin shrugged. He had thought about this already and had an answer prepared, but he preferred that Gallinule believed him to be thinking the problem through even as they spoke. 'Of course, I don't really think there's a moon down there. But there could still be something orbiting.'
'Such as?' Pauraque said.
'A black hole, for instance. A small one - say a tenth of the mass of Cinder, with a light-trapping radius of about a millimetre. We'd have missed that kind of perturbation to Ghost's gravitational field until now. It wouldn't feel the atmosphere at all, not on the kind of timescales we're concerned with. But as the hole passed, the atmosphere would be tugged towards it for hundreds of kilometres along its track. Any chance that's your anomaly?'
There was a grudging silence before Pauraque answered. 'I admit that at the very least it's possible. We more or less arrived at the same conclusion. Who knows how such a thing ended up inside Ghost, but it could have happened.'
'Maybe someone put it there deliberately.'
'We'll know soon enough. The storm's due any moment now.'
She was right. The storm focus - whatever it was - moved at forty kilometres per second relative to Ghost's core, but since Ghost's equatorial cloud-layers were already rotating at a quarter of that speed, and in the same sense as the focus, the storm only moved at thirty kilometres per second against the atmosphere. Which, Merlin thought, was still adequately fast.
He told the cabin windows to amplify the available light, gathering photons from beyond the visible band and shifting them into the optical. Suddenly it was as if the overlaying veils had been stripped away; sunlight flooded the canyons and crevasses of cloud through which they were flying. The liquid hydrogen ocean began only a few tens of kilometres below them, under a transition zone where the atmospheric gases became steadily more fluidic. It was blood-hot down there; pressures nudged towards one hundred atmospheres. Not far below the sea they would climb into the thousands, at temperatures hot enough to melt machines.
And now something climbed above the horizon to the west. Tyrant began to shriek alarms, its dull machine-sentience comprehending that there was something very wrong nearby, and that it was a wrongness approaching at ferocious speed. The storm focus gathered clouds as it moved, tugging them violently out of formation. To Merlin's eyes, the way it moved reminded him of something from his childhood, something glimpsed moving through Plenitude's tropical waters with predatory swiftness: a darting mass of whirling tentacles.
'We're too high,' Pauraque said. 'I'm taking us lower. I want to be much closer to the focus when it arrives.'
Before he could argue, Merlin saw the violet thrust spikes of the other ship. It slammed away, dwindling into the soupy stillness of the upper transition zone. He thought of a fish descending into some lightless ocean trench, into benthic darkness.
'Watch your shielding,' he said, as he dived his own ship after them.
'Pressure's still within safe limits,' Gallinule said, though they both knew that what now constituted safe was not quite the usual sense of the word. 'I'll pull up if the rivets start popping, trust me.'
'It's not just the pressure that worries me. If there's a black hole in that focus, there's also going to be a blast of gamma rays from the matter being sucked in.'
'We haven't seen anything yet. Maybe the flux is masked by the clouds.'
'You'd better hope it is.'
Merlin was suited up, wearing the kind of high-pressure mobility armour he had only ever worn before in warcreche simulations. The armour was prized technology, many kiloyears old; nothing like it now within the Cohort's technical reach. He hoped Gallinule and Pauraque were similarly prudent. If the hull collapsed, the suits might only give them a few more minutes of life, but near something as unpredictable and chaotic as a miniature black hole, there was no such thing as too much shielding.
'Merlin?' Gallinule said. 'We've lost a power node. Damn jury-rigged things. If there's a pressure wave before the focus we might start to buckle--'
'You can't risk it. Pull up and out. We can come back again on the next pass, three hours from now.'
He had seen accretion discs, the swirls of matter around stellar-mass black holes and neutron stars, and what he saw near the storm's focus looked very similar: a spiralling concentration of cloud, tortured into rainbow colours as strange, transient chemistries came into play. They were so deep in the transition zone here that even tiny pressure changes were enough to condense the air into its fluid state. Lightning cartwheeled across the focus, driven by static differentials in the moving air masses. Merlin checked the range: close now, less than two hundred kilometres away.
And something was wrong.
Pauraque's ship was sinking too far, drifting too close to the heart of the storm. They were above it now, but their rate of descent would bring them close to the focus by the time it arrived.
'Force and wisdom; I told you to pull up, not go deeper!'
'We have a problem. Can't reshape the hull on our remaining nodes. No aerodynamic control.' Gallinule's voice was calm, but Merlin knew his brother was terrified.
'Vector your thrust.'
'Hell's teeth, what do you think I'm trying to do?'
No good. He watched the violet spikes of the other ship's thrusters stab in different directions, but there was nothing Gallinule could do to bring them out of their terminal descent. Merlin thought of the mods Gallinule had recommended. Unless he had added some hidden improvements, the other ship would implode in ten or fifteen seconds. There would be no surviving that.
'Listen to me,' Merlin said. 'You have to equalise pressure with the outside, or that hull's going to implode.'
'We'll lose the ship that way.'
'Don't argue, just do it! You have no more than ten seconds to save yourselves!'
He closed his eyes and hoped they were both suited. Or perhaps it would be better if they were not. To die by hull implosion would be swift, after all. The inrushing walls would move faster than any human nerve impulses.
On the magnified view of the other ship he saw a row of intakes flicker open along the dorsal line. Soup-thick atmosphere would have slammed in like an iron fist. Maybe their suits were good enough to withstand that shock.
He hoped so.
The thrust flames died out. Running lights and fluorescent markings winked out. A moment later he watched the other ship come apart like something fashioned from gossamer. Debris lingered for an instant before being crushed towards invisibility.
And two bulbously suited human figures fell through the air, drifting apart as they were caught in the torpid currents that ran through the transition zone. For a moment the suits were androform, but then their carapaces flowed liquidly towards smooth egg-shapes, held rigid by the same principle that still protected Merlin's ship. They were alive - he was sure of that - but they were still sinking, still heavier than the air they displaced. The one that was now falling fastest would pass the storm at what he judged to be a safe distance. The other would fall right through the storm's eye.
He thought of the focus of the storm: a seething eye of flickering gamma rays, horrific gravitational stress and intense pressure eddies. They had not seen it yet, but he could be sure that was what it would be like. A black hole, even a small one, was no place to be near.
'Final warning,' Tyrant said, bypassing all his overrides. 'Pressure now at maximum safe limit. Any further increase in--'
He made his decision.
Slammed Tyrant screaming towards the survivor who was headed towards the eye. It would be close - hellishly so. Even the extra margins he had built into this ship's hull would be pushed perilously close to the limit. On the cabin window, cross-hairs locked around the first falling egg. Range: eleven kilometres and closing. He computed an approach vector and saw that it would be even closer than he had feared. They would be arcing straight towards the eye by the time he had the egg aboard. Seven kilometres. There would not be time to bring the egg aboard properly. The best he could do would be to open a cavity in the hull and enclose it. Frantically he told Tyrant what he needed; by the time he was done, range was down to three kilometres.