If there'd been more time, he thought, we'd have come with submarines, not spacecraft ...
It was a dismal place to even think about spending any time in. But in that respect it made perfect sense. The thick atmosphere would make it easy to hide a modestly sized floating base, smothering infrared emissions. They would probably have to sleep during the hideaway period, but that was no great hardship. Better than spending decades awake, always knowing that beyond the walls was that crushing force constantly trying to squash you out of existence.
But there was something down here, Gallinule had said. Something that might count against using Ghost as a hideaway.
They had to know what it was.
'Warning,' said Tyrant. 'External pressure now thirty bars. Probability of hull collapse in five minutes is now five per cent.'
Merlin killed the warning system. It did not know about the augmentations he had made to the hull armouring, but it was still unnerving. But Pauraque and Gallinule were lower yet, and their navigational transponder was still working.
If they were daring him to go deeper, he would accept.
'Merlin?' said his brother's voice, trebly with echoes from the atmospheric interference. 'So you decided to join us after all. Did you bring Sayaca with you?'
'I'm alone. I didn't see any point in endangering two of us.'
'Shame. Well, I hope you implemented those hull mods, or this is going to be a brief conversation.'
'Just tell me what it is we're expecting to see down here. You mentioned something unexpected.'
Pauraque's voice now. 'There's a periodic pressure phenomenon moving through the atmosphere, like a very fast storm. What it is, we don't know. Until we understand it, we can't be certain that hiding inside Ghost will work.'
Merlin nodded, suddenly seeing Gallinule's angle. His brother would want the phenomenon to prove hazardous just so that his plan could triumph over Pauraque's. It was an odd attitude, especially as Pauraque and Gallinule were now said to be lovers, but it was nothing unusual as far as his brother was concerned.
'I take it you have a rough idea when we can expect to see this thing?'
'Reasonably good,' Pauraque said. 'Approach us and follow our vector. We're going deeper, so watch those integrity readings.'
As if to underline her words, the hull chose that moment to creak - a dozen alerts sounding. Merlin grimaced, silencing the alarms, and gunned Tyrant towards the other ship.
Ghost was a classic gas giant, three hundred times more massive than Cinder. Most of the planet was hydrogen in its metallic state, overlaid by a deep ocean of merely liquid hydrogen. The cloud layers, which seemed so immense - and which gave the world its subtle bands of colour - were compressed into only a few hundred kilometres of depth. Less than a hundredth of the planet's radius, yet those frigid, layered clouds of ammonia, hydrogen and water were as deep as humans could go. Pauraque wanted to hide at the lowest layer above the transition zone where the atmosphere thickened into a liquid-hydrogen sea, under a crystal veil of ammonium hydro-sulphide and water-ice.
Ahead, he could now see the glint of the other ship's thrusters, illuminating sullen cloud formations as it passed through them. Only a few kilometres ahead.
'You mentioned that the phenomenon was periodic,' Merlin said. 'What exactly did you mean by that?'
'Exactly what I said,' came Pauraque's reply, much clearer now. 'The pressure wave - or focus - moves around Ghost once every three hours.'
'That's much faster than any cyclone.'
'Yes.' The icy distaste in Pauraque's voice was obvious. She did not enjoy having a civil conversation with him. 'Which is why we consider the phenomenon sufficiently--'
'It could be in orbit.'
'What?'
Merlin checked the hull readouts again, watching as pressure hotspots flowed liquidly from point to point. Rendered in subtle colours, they looked like diffraction patterns on the scales of a sleek, tropical fish.
'I said it could be in orbit. If one of Ghost's moons was in orbit just above the top of the cloud layer, three hours is how long it would take to go around. The time would only be slightly less for a moon orbiting just below the cloud layer, where we are.'
'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.
He felt faint, phantom deceleration as Tyrant matched trajectories with the egg and brought itself in for the rendezvous. The egg left a trail of bubbles behind it as it dropped, evidence of the transition to ocean. Somewhere on Tyrant's skin, a cavity puckered open, precisely shaped to accept the egg. They tore through rushing curtains of cloud. In a few moments he would be near enough to see the eye, he knew. One kilometre . . . six hundred metres. Three hundred.
The faintest of thumps as the egg was captured. Membranes of hull locked over the prize and resealed. Whoever he had saved was as safe now as Merlin.
Which was really saying very little.
'Instigate immediate pull-up. Hull collapse imminent. Severe pressure transition imminent.'
He was through the eye now, perhaps only two or three kilometres from the sucking point of the black hole. He had expected to see the clouds drawn into a malignant little knot, with a flickering glint of intense light at the heart of the whirlpool, but there was nothing, just clear skies. There was a local gravitational distortion, but it was nowhere near as severe as he had expected. Merlin glanced at the radiation alarms, but they were not showing anything unusual.
No hint of gamma radiation.
He wanted time to think, wanted to work out how he could be this close to a black hole and feel no radiation, but what was coming up below instantly demanded his attention. There was the other egg, tumbling below, wobbling as if in a mirage. Pressure was distorting it, readying to crush it. And down below, slumbering under the transition zone, was the true hydrogen sea. In a few seconds the other egg would be completely immersed in that unimaginably dense blackness and it would all be over. For a moment he considered swooping in low; trying to snatch the egg before it hit. He ran the numbers and saw the chilling truth.
He would have to enter the sea as well.
Merlin gave Tyrant its orders and closed his eyes. Even in the cushioning embrace of his suit, the hairpin turn as the ship skimmed the ocean would still not be comfortable. It would probably push him below consciousness. Which, he thought, might turn out to be the final mercy.
The sea's hazy surface came up like a black fog.
Thought faded for an instant, then returned fuzzily; and now through the windows he saw veils of cloud towards which he was climbing. The feeling of having survived was godlike. Yet something was screaming. The ship, he realised. It had sloughed millimetres of hull to stay intact. He prayed that the damage would not prevent him from getting home.
'The second egg . . .' Merlin said. 'Did we get it?'
Tyrant was clever enough - just - to know what he meant. 'Both eggs recovered.'
'Good. Show me . . .'
Proctors carried the first egg into the cabin, fiddling with it until they persuaded it to revert to androform shape. When the facial region became transparent he saw that it was Gallinule that this egg had saved, although his brother was clearly unconscious. Not dead though: he could tell that from the egg's luminous readouts. He felt a moment of pure, unadulterated bliss. He had saved Gallinule, but not selfishly. He had not known which of the two eggs had been falling towards the eye. In fact, he did not even know that this was that egg. Had he plucked his brother from the sea, instants before the ocean would have crushed him?
But then he saw the other egg. The proctors, stupid to the end, had seen fit to bring it into the cabin. They carried it like a trophy, as if it were something he would be overjoyed to see. But it was barely larger than a space helmet.
PART FOUR
'I think I know what killed her,' Sayaca
said.
The three of them had agreed to meet within the Palace of Eternal Dusk. Sayaca had arranged a demonstration, casting into the sky vast projected shapes, which she orchestrated with deft gestures.
'It wasn't a black hole, was it?' Gallinule said.
'No.' She took his hand in both of hers, comforting him as they dug through the difficult memory of Pauraque's death. It had happened months ago, but the pain of it was still acute for Gallinule. Merlin watched from one side, lingeringly resentful at the tenderness Sayaca showed his brother. 'I think it was something a lot stranger than a black hole. Shall I show you?'