3001 The Final Odyssey

chapter 17 Ganymede
It was unusual for Frank Poole to oversleep, but he had been kept awake by strange dreams. Past and present were inextricably mixed; sometimes he was on Discovery, sometimes in the Africa Tower - and sometimes he was a boy again, among friends he had thought long-forgotten.

Where am I? he asked himself as he struggled up to consciousness, like a swimmer trying to get back to the surface. There was a small window just above his bed, covered by a curtain not thick enough to completely block the light from outside. There had been a time, around the mid-twentieth century, when aircraft had been slow enough to feature First Class sleeping accommodation: Poole had never sampled this nostalgic luxury, which some tourist organizations had still advertised in his own day, but he could easily imagine that he was doing so now.

He drew the curtain and looked out. No, he had not awakened in the skies of Earth, though the landscape unrolling below was not unlike the Antarctic. But the South Pole had never boasted two suns, both rising at once as Goliath swept towards them.

The ship was orbiting less than a hundred kilometres above what appeared to be an immense ploughed field, lightly dusted with snow. But the ploughman must have been drunk - or the guidance system must have gone crazy - for the furrows meandered in every direction, sometimes cutting across each other or turning back on themselves. Here and there the terrain was dotted with faint circles -ghost craters from meteor impacts aeons ago.

So this is Ganymede, Poole wondered drowsily. Mankind's furthest outpost from home! Why should any sensible person want to live here? Well, I've often thought that when I've flown over Greenland or Iceland in winter-time...

There was a knock on the door, a 'Mind if I come in?', and Captain Chandler did so without waiting for a reply.

'Thought we'd let you sleep until we landed - that end-of-trip party did last longer than I'd intended, but I couldn't risk a mutiny by cutting it short.'

Poole laughed.

'Has there ever been a mutiny in space?'

'Oh, quite a few but not in my time. Now we've mentioned the subject, you might say that Hal started the tradition... sorry - perhaps I shouldn't - look - there's Ganymede City!'

Coming up over the horizon was what appeared to be a criss-cross pattern of streets and avenues, intersecting almost at right-angles but with the slight irregularity typical of any settlement that had grown by accretion, without central planning. It was bisected by a broad river - Poole recalled that the equatorial regions of Ganymede were now warm enough for liquid water to exist - and it reminded him of an old wood-cut he had seen of medieval London.

Then he noticed that Chandler was looking at him with an expression of amusement... and the illusion vanished as he realized the scale of the 'city'.

'The Ganymedeans,' he said dryly, 'must have been rather large, to have made roads five or ten kilometres wide.'

'Twenty in some places. Impressive, isn't it? And all the result of ice stretching and contracting. Mother Nature is ingenious... I could show you some patterns that look even more artificial, though they're not as large as this one.'

'When I was a boy, there was a big fuss about a face on Mars. Of course, it turned out to be a hill that had been carved by sand-storms... lots of similar ones in Earth's deserts.'

'Didn't someone say that history always repeats itself? Same sort of nonsense happened with Ganymede City - some nuts claimed it had been built by aliens. But I'm afraid it won't be around much longer.'

'Why?' asked Poole in surprise.

'It's already started to collapse, as Lucifer melts the permafrost. You won't recognize Ganymede in another hundred years... there's the edge of Lake Gilgamesh - if you look carefully - over on the right-'

'I see what you mean. What's happening - surely the water's not boiling, even at this low pressure?'

'Electrolysis plant. Don't know how many skillions of kilograms of oxygen a day. Of course, the hydrogen goes up and gets lost - we hope.'

Chandler's voice trailed off into silence. Then he resumed, in an unusually diffident tone: 'All that beautiful water down there - Ganymede doesn't need half of it! Don't tell anyone, but I've been working out ways of getting some to Venus.'

'Easier than nudging comets?'

'As far as energy is concerned, yes - Ganymede's escape velocity is only three klicks per second. And much, much quicker - years instead of decades. But there are a few practical difficulties..

'I can appreciate that. Would you shoot it off by a mass-launcher?'

'Oh no - I'd use towers reaching up through the atmosphere, like the ones on Earth, but much smaller. We'd pump the water up to the top, freeze it down to near absolute zero, and let Ganymede sling it off in the right direction as it rotated. There would be some evaporation loss in transit, but most of it would arrive - what's so funny?'

'Sorry - I'm not laughing at the idea - it makes good sense. But you've brought back such a vivid memory. We used to have a garden sprinkler - driven round and round by its water jets. What you're planning is the same thing - on a slightly bigger scale... using a whole world...'

Suddenly, another image from his past obliterated all else. Poole remembered how, in those hot Arizona days, he and Rikki had loved to chase each other through the clouds of moving mist, from the slowly revolving spray of the garden sprinkler.

Captain Chandler was a much more sensitive man than he pretended to be: he knew when it was time to leave.

'Gotta get back to the bridge,' he said gruffly. 'See you when we land at Anubis.'