‘More yes than no. We have other arts. Tell me why you are here.’
She frowned. ‘We have a right to be here.’ She waved an arm over the sky. ‘Some day humans are going to reach every star in the sky, and live there.’
‘Why?’
‘Because if we don’t, somebody else will.’
‘Is that all you do?’ the ghost asked. ‘Fly to the stars and build cities and compete?’
‘No. We have music and poetry and other stuff.’ Defensively, she plodded on through deepening snow. ‘Soon we’ll change this world. We’re going to terraform it.’ She had to explain what that meant. ‘It will be a heroic project. It will require hard work, ingenuity and perseverance. Also we have brought creatures with us that are used to the cold. We found them on an ice moon a long way from our sun, a place called Port Sol. They have liquid helium for blood. Now we farm them. They can live here, even before the terraforming.’
‘How remarkable. But there are already creatures living here.’
‘We’ll put them in cases,’ said Minda. ‘Or zoos.’
‘We, my kind, can live here, on this cold world, without making it warm.’
‘Then you’ll have to leave,’ she snapped.
She reached the outskirts of the city.
It was a gridwork of foundations and low walls, all of it half-buried under a blanket of rock-hard water ice and frozen air. The buildings and roads seemed to follow a pattern of interlocking hexagons, quite unlike the cramped, organic, circle-based design of modern Conurbations on Earth, or the rectangular layout of many older, pre-Qax human settlements.
As she walked along what might once have been a street, the pain in her hands and feet seemed to be metamorphosing to an ominous numbness.
The ghost seemed to notice this. ‘You continue to lose heat,’ it said. ‘Shivering is no longer enough to warm you. Now your body is drawing heat back from your extremities to your core. Your limbs are stiffening—’
‘Shut up,’ she hissed.
She found a waist-high fragment of wall protruding from the layers of ice. She brushed at it with her glove; loose snow fell away, revealing a surface of what looked like simple brick. But it crumbled at her touch, perhaps frost-shattered.
She walked on into what might once have been a room, a space bounded by six broken walls. Though there were many rooms close by here – clustered like a honeycomb, closer than would have been comfortable for people – it was hard to believe the inhabitants of this place had been so different from humans.
She wondered what it had been like here, before.
Once, Snowball had been Earth-like. There had been continents, oceans of water, and life – based on an organic chemistry of carbon, oxygen and water, like Earth life, and it had worked to create an atmosphere of oxygen and nitrogen, not so dissimilar to Earth’s. And there had been people here: people who had built cities, and breathed air, and perhaps gazed at the stars.
But the long afternoon of this world had been disturbed.
Its sun had suffered a chance close encounter with another star. It was an unlucky, unlikely event, Minda knew; away from the Galaxy’s centre the stars were thinly scattered. As the interloper fell through the orderly heart of this world’s home system, there must have been immense tides, ocean waves that ground cities to dust, and earthquakes, a flexing of the rocky crust itself.
And then, at the intruder’s closest approach, Snowball was slingshot out of the heart of its system.
The home sun had receded steadily. Ice spread from polar caps across the land and the oceans, until much of the planet was clad in a thick layer of hardening water ice. At last the very air began to rain out of the sky, liquid oxygen and nitrogen running down the frozen river valleys to pool atop the vast ice sheets, forming a softer snow metres thick.
She wondered what had become of the people. Had they retreated underground into caves? Had they fled their planet altogether – perhaps even migrated to new worlds surrounding the wrecking star?
‘This world itself is not without inner heat,’ the ghost said softly. ‘The deep heart of a planet this size would scarcely notice the loss of its sun.’
‘The volcano,’ Minda said dully.
‘Yes. That is one manifestation. And vents of hot material on the spreading seabed have even kept the lower levels of the ocean unfrozen. We believe there may still be active life forms there feeding on the planet’s geothermal heat. But they must have learned to survive without oxygen…’
‘Do you have that on your world? Deep heat, water under the ice?’
‘Yes. But my world is small and cold; long ago it lost much of its inner heat.’
‘The world I come from is bigger than this frozen ruin,’ she said, spreading her arms wide. ‘It has lots of heat. And it is a double world. It has a Moon. I bet even the Moon is bigger than your world.’
‘Perhaps it is,’ the ghost said. ‘It must be a wonderful place.’
‘Yes, it is. Better than your world. Better than this.’
‘Yes.’
She was very tired. She didn’t seem to be hungry, or thirsty. She wondered how long it was since she had eaten. She stared at the frozen air around her, trying to remember why she had come here. An idea sparked, fitfully.
She got to her knees. She could feel the diamond grid of the suit’s heating elements press into the flesh of her legs. She swept aside the loose snow, but beneath there was only a floor of hard water ice.
‘There’s nothing here,’ she said dully.
‘Of course not,’ the ghost said gently. ‘The tides washed it all away.’
She began to pull together armfuls of loose snow. Much of it melted and evaporated, but slowly she made a mound of it in the centre of the room.
‘What are you doing?’
‘Maybe I can breathe this stuff.’ She knew little about the flitter’s systems. Maybe there was some hopper into which she could cram this frozen air.
But the ghost was talking to her again, its voice gentle but persistent, unwelcome. ‘Your body is continuing to manage the crisis. Carbohydrates which would normally feed your brain are now being burnt to generate more heat. Your brain, starved, is slowing down; your coordination is poor. Your judgement is unreliable.’
‘I don’t care,’ she growled, scraping at the frozen air.
‘Your plan is not likely to succeed. Your biology requires oxygen. But the bulk of this snow is nitrogen. And there are trace compounds which may be toxic to you. Does your craft contain filtering systems which—’
Minda drove her suited arm through the pile of air, scattering it in a cloud of vapour. ‘Shut up. Shut up.’
She walked back to the flitter. By now it felt as if she was floating, like a ghost herself.
The silver ghost told her about the world it came from. It was like Snowball, and yet it was not.
The ghosts’ world was once Earth-like, if smaller than Earth: blue skies, a yellow sun. But even as the ghosts climbed to awareness their sun evaporated, killed by a companion pulsar. It was a slower process than the doom of Snowball, but no less lethal. The oceans froze and life huddled inward; there was frantic evolutionary pressure to find ways to keep warm.
Then the atmosphere started snowing.
The ghosts had gathered their fellow creatures around them and formed themselves into compact, silvered spheres, each body barely begrudging an erg to the cold outside. Finally clouds of mirrored life forms rolled upwards. The treacherous sky was locked out – but every stray wisp of the planet’s internal heat was trapped.