In the morning Beth served a breakfast of more tea and food from her stock: mostly potato, boiled and dried. The new arrivals ate hungrily but without relish, and Stef could see Beth was faintly embarrassed at not being able to offer them anything better, a totally illogical feeling but understandable.

Titus organised a party – himself, Clodia, Ari and Inguill – to extend that latrine ditch. ‘It has to be done!’

And Beth led Stef, Mardina and Chu, bearing his pack with the ColU, on a short tour of her little homestead.

It was a well-chosen spot, Stef could see immediately. Beth had made her camp on top of a low rise, away from any obvious water courses; she’d have lived through all but the most monumental flooding events. But there was a stream for drinking water on the lower ground only a short distance away, and a forest clump on top of the rise that could provide fuel for burning and other materials. And Beth had put in a lot of work. In addition to her bubble shelter she had already started to construct lean-tos and tepees, supported by the sapling-like stems of young native trees, and with dead stems woven to create a kind of thatch. Under the lean-tos, and in holes in the ground, she’d built up a food store: the remains of the rations she’d brought through the Hatch, as well as wild food she’d gathered from the countryside. She was even building a kind of cart.

As they looked around the little compound, Stef was reminded that Beth Eden Jones was after all a pioneer, a daughter of pioneers, who had survived in this unearthly wilderness for decades. And Beth, apparently instinctively, had gone to work applying all the wisdom she’d acquired in those days – wisdom, Stef supposed, that had been entirely useless back on Earth, after she and her parents had returned through the Hatch to Mercury. It must have felt good to use those skills, to find purpose again.

Beth showed them her clocks.

She’d set up a whole array of them, using sand and water dribbling through funnels woven from dead stems: improvised hourglasses, all running independently. And on a tree trunk nearby she was notching off the days. ‘I have two chronometers,’ she said. ‘My wristwatch, and a timekeeper in the pack Earthshine gave me from his support unit. This homemade stuff is for backups for when the power eventually fails—’

‘Timing will no longer be a problem,’ the ColU said blandly. ‘I have internal chronometers, which—’

‘Which will work until you run out of power,’ Beth said firmly. ‘I did learn some basic disciplines from my ISF-lieutenant mother, ColU. You should know that. You always have backups.’

The ColU seemed to chuckle, to Stef’s hearing. Since when had a farm robot learned to chuckle? It said now, ‘Just like old times, Beth Eden Jones.’

‘Sure it is. I’m aiming for bigger barrels, smaller nozzles, that won’t require refilling – oh, for several days, enough time for me to make decent excursions from this site without losing track of time.’

‘Of course,’ Mardina said, ‘you won’t need all that now, Mother. Not now that we’re all here. As long as there’s one person to stay behind and tend the fire and change over the clocks and whatever—’

She was casually holding the hand of the silent Chu Yuen, Stef noticed. She risked a glance at Beth, who raised her eyebrows in response. She’s not letting that boy out of her sight, and to hell with doe-eyed Clodia.

Beth said breezily, ‘If I’d known a whole gang of you were going to turn up I’d not have gone to all this trouble, would I? In the meantime, come and see what else I’ve built.’

She seemed proud of the plots she’d cleared, and started to seed with crops of her own. ‘I may never get to see these potatoes and peas and whatnot become fully domesticated. But it’s a start.’

‘Of course,’ the ColU said, ‘now that I am here to advise we can make much faster progress.’

Beth fumed. ‘Advise? I was doing pretty well before you ever showed up, you clanking heap of—’

‘The work’s doing you good, Mother,’ Mardina said quickly. ‘I haven’t seen you look so fit in years. Or as slim.’

‘Thanks,’ Beth said drily.

‘The crops are also going to be a useful winter larder,’ Stef said, ‘in case Prox ever decides to let us down again.’

‘A future winter is very unlikely,’ the ColU murmured, peering from the slate on Chu’s chest, its voice muffled by the fabric of the pack. ‘The Proxima Centauri in the sky above is rather different from the beast we knew, Colonel Kalinski. Much less irregular. And the incidence of flares must be a lot lower too.’

‘I figured that,’ Beth said. ‘But I took precautions even so.’ She pointed to a stromatolite garden, a huddle of table-like forms glistening brown in the watery Prox light, only a hundred paces away. ‘I picked out a storm shelter to hide in – hacked away the carapace in advance. Of course we need to extend that so there’s shelter for all of us. But …’ She raised her face to the sky, the heavy bulk of Proxima directly overhead. ‘I don’t know what’s going on here. This is Per Ardua. But why is it so different from what I remember? Even the jonbar hinges didn’t change Earth itself that much, aside from what humanity was able to do to it.’

‘We are here to seek answers to such questions,’ the ColU said. ‘That is true even of Earthshine. Especially true of him, even if his method of enquiry is somewhat destructive. Chu Yuen, would you please turn around? Pan the slate – let me see the sky, the landscape from this vantage … And, Beth Eden Jones, would you show me a handful of the soil you are so assiduously cultivating?’

‘Why do you want to see that? Oh, very well.’

Stef watched the former slave swivel on the spot, slowly, even gracefully. And Mardina was watching him too. He was nineteen, twenty years old now. Having spent a few days with him Stef knew that Chu Yuen was working to get his body in better physical condition, and he studied, too, reading from slates, generally alone. All this was in order better to serve the ColU, he said. Stef felt a kind of faint echo of lust of her own. If she could only shave off a few decades, the Mardina-Clodia-Chu triangle could well become a quadrilateral …

Beth, her cupped hands holding a mass of soil, was grinning at Stef knowingly.

‘Beth Eden Jones, please hold the soil up before the slate. That’s it – ah! See that?’

Stef and Mardina closed in to see. Something was wriggling in the dark brown soil, pale and pink. It was an earthworm, Stef saw with a jolt of wonder. There could be nothing more mundane than such a thing, and yet here it was burrowing through the ground on a world of another star.

‘This is no surprise,’ the ColU said. ‘A potato from Earth needs soil from Earth, which is more than just dirt; soil is a complex and nutrient-rich structure in its own right. Do you remember, Beth Eden Jones, how my primary duty in the days of pioneering with your parents was to manufacture soil, using Per Arduan dirt as the basis?’

Beth laughed. ‘I remember we had to haul tonnes of it with us when we moved.’

‘I even had a miniature womb in my lost body, within which earthworms and other necessary creatures could be grown from stored cells. Of course I used these facilities to buy us acceptance by the Romans, on the planet of Romulus.

‘But I was designed for Per Ardua, as it was. Now look at what we find. A soil that is evidently neither Arduan nor terrestrial, a soil that is evidently capable, still, of supporting Arduan life, like the stems, and yet an earthworm that might have been airlifted from a Kansas farm wriggles through it without hindrance.’

Beth was wide-eyed, looking down at the worm with new understanding. ‘You know, when I was digging my fields I forked over these things without even thinking about it. Yet here they are.’

‘Colonel Kalinski, how long do you think it would take for earthworms to permeate the continents of Per Ardua? How long for the two ecologies to mesh in this way?’