6 – The Greening of Ganymede

   Rolf van der Berg was the right man, in the right place, at the right time; no other combination would have worked. Which, of course, is how much of history is made.
   He was the right man because he was a second-generation Afrikaner refugee, and a trained geologist; both factors were equally important. He was in the right place, because that had to be the largest of the Jovian moons – third outwards in the sequence Io, Europa, Ganymede, Callisto.
   The time was not so critical, for the information had been ticking away like a delayed-action bomb in the data banks for at least a decade. Van der Berg did not encounter it until '57; even then it took him another year to convince himself that he was not crazy – and it was '59 before he had quietly sequestered the original records so that no-one could duplicate his discovery. Only then could he safely give his full attention to the main problem: what to do next.
   It had all begun, as is so often the case, with an apparently trivial observation in a field which did not even concern van der Berg directly. His job, as a member of the Planetary Engineering Task Force, was to survey and catalogue the natural resources of Ganymede; he had little business fooling around with the forbidden satellite next door.
   But Europa was an enigma which no-one – least of all its immediate neighbours – could ignore for long. Every seven days it passed between Ganymede and the brilliant minisun that had once been Jupiter, producing eclipses which could last as long as twelve minutes. At its closest, it appeared slightly smaller than the Moon as seen from Earth, but it dwindled to a mere quarter of that size when it was on the other side of its orbit.
   The eclipses were often spectacular. Just before it slid between Ganymede and Lucifer, Europa would become an ominous black disc, outlined with a ring of crimson fire, as the light of the new sun was refracted through the atmosphere it had helped to create.
   In less than half a human lifetime, Europa had been transformed. The crust of ice on the hemisphere always facing Lucifer had melted, to form the Solar System's second ocean. For a decade it had foamed and bubbled into the vacuum above it, until equilibrium had been reached. Now Europa possessed a thin but serviceable – though not to human beings – atmosphere of water vapour, hydrogen sulphide, carbon and sulphur dioxides, nitrogen, and miscellaneous rare gases. Though the somewhat misnamed 'nightside' of the satellite was still permanently frozen, an area as large as Africa now had a temperate climate, liquid water, and a few scattered islands.
   All this, and not much more, had been observed through telescopes in Earth orbit. By the time that the first full-scale expedition had been launched to the Galilean moons, in 2028, Europa had already become veiled by a permanent mantle of clouds. Cautious radar probing revealed little but smooth ocean on one face, and almost equally smooth ice on the other; Europa still maintained its reputation as the flattest piece of real estate in the Solar System. Ten years later, that was no longer true: something drastic had happened to Europa. It now possessed a solitary mountain, almost as high as Everest, jutting up through the ice of the twilight zone. Presumably some volcanic activity – like that occurring ceaselessly on neighbouring Io – had thrust this mass of material skywards. The vastly increased heat-flow from Lucifer could have triggered such an event.
   But there were problems with this obvious explanation. Mount Zeus was an irregular pyramid, not the usual volcanic cone, and radar scans showed none of the characteristic lava flows. Some poor-quality photographs obtained through telescopes on Ganymede, during a momentary break in the clouds, suggested that it was made of ice, like the frozen landscape around it. Whatever the answer, the creation of Mount Zeus had been a traumatic experience for the world it dominated, for the entire crazy-paving pattern of fractured ice floes over the nightside had changed completely.
   One maverick scientist had put forward the theory that Mount Zeus was a 'cosmic iceberg' – a cometary fragment that had dropped upon Europa from space; battered Callisto gave ample proof that such bombardments had occurred in the remote past. The theory was very unpopular on Ganymede, whose would-be colonists already had sufficient problems.
   They had been much relieved when van der Berg had refuted the theory convincingly; any mass of ice this size would have shattered on impact – and even if it hadn't, Europa's gravity, modest though it was, would have quickly brought about its collapse. Radar measurements showed that though Mount Zeus was indeed steadily sinking, its overall shape remained completely unaltered. Ice was not the answer.
   The problem could, of course, have been settled by sending a single probe through the clouds of Europa. Unfortunately, whatever was beneath that almost permanent overcast did not encourage curiosity.

   ALL THESE WORLDS ARE YOURS – EXCEPT EUROPA.
   ATTEMPT NO LANDINGS THERE.

   That last message relayed from the spaceship Discovery just before its destruction had not been forgotten, but there had been endless arguments about its interpretation. Did 'landings' refer to robot probes, or only to manned vehicles? And what about close flybys – manned or unmanned? Or balloons floating in the upper atmosphere?
   The scientists were anxious to find out, but the general public was distinctly nervous. Any power that could detonate the mightiest planet in the Solar System was not to be trifled with. And it would take centuries to explore and exploit Io, Ganymede, Callisto and the dozens of minor satellites; Europa could wait.
   More than once, therefore, van der Berg had been told not to waste his valuable time on research of no practical importance, when there was so much to be done on Ganymede. ('Where can we find carbon – phosphorus – nitrates for the hydroponic farms? How stable is the Barnard Escarpment? Is there any danger of more mudslides in Phrygia?' And so on and so forth...) But he had inherited his Boer ancestors' well-deserved reputation for stubbornness: even when he was working on his numerous other projects, he kept looking over his shoulder at Europa.
   And one day, just a few hours, a gale from the nightside cleared the skies about Mount Zeus.

7 – Transit

   'I too take leave of all 1 ever had...'
   From what depths of memory had that line come swimming up to the surface? Heywood Floyd closed his eyes, and tried to focus on the past. It was certainly from a poem – and he had hardly read a line of poetry since leaving college. And little enough then, except during a short English Appreciation Seminar.
   With no further clues, it might take the station computer quite a while – perhaps as much as ten minutes – to locate the line in the whole body of English literature. But that would be cheating (not to mention expensive) and Floyd preferred to accept the intellectual challenge.
   A war poem, of course – but which war? There had been so many in the twentieth century.
   He was still searching through the mental mists when his guests arrived, moving with the effortless, slow-motion grace of longtime one-sixth gravity residents. The society of Pasteur was strongly influenced by what had been christened 'centrifugal stratification'; some people never left the zero gee of the hub, while those who hoped one day to return to Earth preferred the almost normal-weight regime out on the rim of the huge, slowly revolving disc.
   George and Jerry were now Floyd's oldest and closest friends – which was surprising, because they had so few obvious points in common. Looking back on his own somewhat chequered emotional career – two marriages, three formal contracts, two informal ones, three children – he often envied the long-term stability of their relationship, apparently quite unaffected by the 'nephews' from Earth or Moon who visited them from time to time.
   'Haven't you ever thought of divorce?' he had once asked them teasingly.
   As usual, George – whose acrobatic yet profoundly serious conducting had been largely responsible for the comeback of the classical orchestra – was at no loss for words.
   'Divorce – never,' was his swift reply. 'Murder – often.'
   'Of course, he'd never get away with it,' Jerry had retorted. 'Sebastian would spill the beans.'
   Sebastian was a beautiful and talkative parrot which the couple had imported after a long battle with the hospital authorities. He could not only talk, but could reproduce the opening bars of the Sibelius Violin Concerto, with which Jerry – considerably helped by Antonio Stradivari – had made his reputation half a century ago.
   Now the time had come to say goodbye to George, Jerry and Sebastian – perhaps only for a few weeks, perhaps for ever. Floyd had already made all his other farewells, in a round of parties that had gravely depleted the station's wine cellar, and could think of nothing he had left undone.
   Archie, his early-model but still perfectly serviceable comsec, had been programmed to handle all incoming messages, either by sending out appropriate replies or by routing anything urgent and personal to him aboard Universe. It would be strange, after all these years, not to be able to talk to anyone he wished – though in compensation he could also avoid unwanted callers. After a few days into the voyage, the ship would be far enough from Earth to make real-time conversation impossible, and all communication would have to be by recorded voice or teletext.
   'We thought you were our friend,' complained George. 'It was a dirty trick to make us your executors – especially as you're not going to leave us anything.'
   'You may have a few surprises,' grinned Floyd. 'Anyway, Archie will take care of all the details. I'd just like you to monitor my mail, in case there's anything he doesn't understand.'
   'If he won't, nor will we. What do we know about all your scientific societies and that sort of nonsense?'
   'They can look after themselves. Please see that the cleaning staff doesn't mess things up too badly while I'm away – and, if I don't come back – here are a few personal items I'd like delivered – mostly family.'
   Family! There were pains, as well as pleasures, in living as long as he had done.
   It had been sixty-three – sixty-three! – years since Marion had died in that air crash. Now he felt a twinge of guilt, because he could not even recall the grief he must have known. Or at best, it was a synthetic reconstruction, not a genuine memory.
   What would they have meant to each other, had she still been alive? She would have been just a hundred years old by now.
   And now the two little girls he had once loved so much were friendly, grey-haired strangers in their late sixties, with children – and grandchildren! – of their own. At last count there had been nine on that side of the family; without Archie's help, he would never be able to keep track of their names. But at least they all remembered him at Christmas, through duty if not affection.
   His second marriage, of course, had overlain the memories of his first, like the later writing on a medieval palimpsest. That too had ended, fifty years ago, somewhere between Earth and Jupiter. Though he had hoped for a reconciliation with both wife and son, there had been time for only one brief meeting, among all the welcoming ceremonies, before his accident exiled him to Pasteur.
   The meeting had not been a success; nor had the second, arranged at considerable expense and difficulty aboard the space hospital itself – indeed, in this very room. Chris had been twenty then, and had just married; if there was one thing that united Floyd and Caroline, it was disapproval of his choice.
   Yet Helena had turned out remarkably well: she had been a good mother to Chris II, born barely a month after the marriage. And when, like so many other young wives, she was widowed by the Copernicus Disaster, she did not lose her head.
   There was a curious irony in the fact that both Chris I and II had lost their fathers to space, though in very different ways. Floyd had returned briefly to his eight-year-old son as a total stranger; Chris II had at least known a father for the first decade of his life, before losing him for ever.
   And where was Chris these days? Neither Caroline nor Helena – who were now the best of friends – seemed to know whether he was on Earth or in space. But that was typical; only postcards date-stamped CLAVIUS BASE had informed his family of his first visit to the Moon.
   Floyd's card was still taped prominently above his desk. Chris II had a good sense of humour – and of history. He had mailed his grandfather that famous photograph of the Monolith, looming over the spacesuited figures gathered round it in the Tycho excavation, more than half a century ago. All the others in the group were now dead, and the Monolith itself was no longer on the Moon. In 2006, after much controversy, it had been brought to Earth and erected – an uncanny echo of the main building – in the United Nations Plaza. It had been intended to remind the human race that it was no longer alone; five years later, with Lucifer blazing in the sky, no such reminder was needed.
   Floyd's fingers were not very steady – sometimes his right hand seemed to have a will of its own – as he unpeeled the card and slipped it into his pocket. It would be almost the only personal possession he would take when he boarded Universe.
   'Twenty-five days – you'll be back before we've noticed you're gone,' said Jerry. 'And by the way, is it true that you'll have Dimitri onboard?'
   'That little Cossack!' snorted George. 'I conducted his Second Symphony, back in '22.'
   'Wasn't that when the First Violin threw up, during the largo?'

   'No – that was Mahler, not Mihailovich. And anyway it was the brass, so nobody noticed – except the unlucky tuba player, who sold his instrument the next day.'
   'You're making this up!'
   'Of course. But give the old rascal my love, and ask him if he remembers that night we had out in Vienna. Who else have you got aboard?'
   'I've heard horrible rumours about press gangs,' said Jerry thoughtful1y.
   'Greatly exaggerated, I can assure you. We've all been personally chosen by Sir Lawrence for our intelligence, wit, beauty, charisma, or other redeeming virtue.'
   'Not expendability?'
   'Well, now that you mention it, we've all had to sign a depressing legal document, absolving Tsung Spacelines from every conceivable liability. My copy's in that file, by the way.'
   'Any chance of us collecting on it?' asked George hopefully.
   'No – my lawyers say it's iron-clad. Tsung agrees to take me to Halley and back, give me food, water, air, and a room with a view.'
   'And in return?'
   'When I get back I'll do my best to promote future voyages, make some video appearances, write a few articles – all very reasonable, for the chance of a lifetime. Oh yes – I'll also entertain my fellow passengers – and vice versa.'
   'How? Song and dance?'
   'Well, I hope to inflict selected portions of my memoirs on a captive audience. But I don't think I'll be able to compete with the professionals. Did you know that Yva Merlin will be on board?'
   'What! How did they coax her out of that Park Avenue cell?'
   'She must be a hundred and – oops, sorry, Hey.' 'She's seventy, plus or minus five.'
   'Forget the minus. I was just a kid when Napoleon came out.'
   There was a long pause while each of the trio scanned his memories of that famous work. Although some critics considered her Scarlett O'Hara to be her finest role, to the general public Yva Merlin (née Evelyn Miles, when she was born in Cardiff, South Wales) was still identified with Josephine. Almost half a century ago, David Griffin's controversial epic had delighted the French and infuriated the British – though both sides now agreed that he had occasionally allowed his artistic impulses to trifle with the historical record, notably in the spectacular final sequence of the Emperor's coronation in Westminster Abbey.
   'That's quite a scoop for Sir Lawrence,' said George thoughtfully.
   'I think I can claim some credit for that. Her father was an astronomer – he worked for me at one time – and she's always been quite interested in science. So I made a few video calls.'
   Heywood Floyd did not feel it necessary to add that, like a substantial fraction of the human race, he had fallen in love with Yva ever since the appearance of GWTW Mark II.
   'Of course,' he continued, 'Sir Lawrence was delighted – but I had to convince him that she had more than a casual interest in astronomy. Otherwise the voyage could be a social disaster.'
   'Which reminds me,' said George, producing a small package he had been not very successfully hiding behind his back. 'We have a little present for you.'
   'Can I open it now?'
   'Do you think he should?' Jerry wondered anxiously.
   'In that case, I certainly will,' said Floyd, untying the bright green ribbon and unwrapping the paper.
   Inside was a nicely framed painting. Although Floyd knew little of art, he had seen it before; indeed, who could ever forget it?
   The makeshift raft tossing on the waves was crowded with half-naked castaways, some already moribund, others waving desperately at a ship on the horizon. Beneath it was the caption:

   THE RAFT OF THE MEDUSA
   (Theodore Géricault, 1791-1824)

   And underneath that was the message, signed by George and Jerry: 'Getting there is half the fun.'
   'You're a pair of bastards, and I love you dearly,' said Floyd, embracing them both. The ATTENTION light on Archie's keyboard was flashing briskly; it was time to go.
   His friends left in a silence more eloquent than words. For the last time, Heywood Floyd looked around the little room that had been his universe for almost half his life.
   And suddenly he remembered how that poem ended:

   'I have been happy: happy now I go.'

8 – Starfleet

   Sir Lawrence Tsung was not a sentimental man, and was far too cosmopolitan to take patriotism seriously – though as an undergraduate he had briefly sported one of the artificial pigtails worn during the Third Cultural Revolution. Yet the planetarium re-enactment of the Tsien disaster moved him deeply, and caused him to focus much of his enormous influence and energy upon space.
   Before long, he was taking weekend trips to the Moon, and had appointed his son Charles (the thirty-two-million-so! one) as Vice-President of Tsung Astrofreight. The new corporation had only two catapult-launched, hydrogen-fuelled ramrockets of less than a thousand tons empty mass; they would soon be obsolete, but they could provide Charles with the experience that, Sir Lawrence was quite certain, would be needed in the decades ahead. For at long last, the Space Age was truly about to begin.
   Little more than half a century had separated the Wright Brothers and the coming of cheap, mass air transportation; it had taken twice as long to meet the far greater challenge of the Solar System.
   Yet when Luis Alvarez and his team had discovered muon-catalysed fusion back in the 1950s, it had seemed no more than a tantalizing laboratory curiosity, of only theoretical interest. Just as the great Lord Rutherford had pooh-poohed the prospects of atomic power, so Alvarez himself doubted that 'cold nuclear fusion' would ever be of practical importance. Indeed, it was not until 2040 that the unexpected and accidental manufacture of stable muonium-hydrogen 'compounds' had opened up a new chapter of human history – exactly as the discovery of the neutron had initiated the Atomic Age.
   Now small, portable nuclear power plants could be built, with a minimum of shielding. Such enormous investments had already been made in conventional fusion that the world's electrical utilities were not – at first – affected, but the impact on space travel was immediate; it could be paralleled only by the jet revolution in air transport of a hundred years earlier.
   No longer energy-limited, spacecraft could achieve far greater speeds; flight times in the Solar System could now be measured in weeks rather than months or even years. But the muon drive was still a reaction device – a sophisticated rocket, no different in principle from its chemically fuelled ancestors; it needed a working fluid to give it thrust. And the cheapest, cleanest, and most convenient of all working fluids was – plain water.
   The Pacific Spaceport was not likely to run short of this useful substance. Matters were different at the next port of call – the Moon. Not a trace of water had been discovered by the Surveyor, Apollo, and Luna missions. If the Moon had ever possessed any native water, aeons of meteoric bombardment had boiled and blasted it into space.
   Or so the selenologists believed; yet clues to the contrary had been visible, ever since Galileo had turned his first telescope upon the Moon. Some lunar mountains, for a few hours after dawn, glitter as brilliantly as if they are capped with snow. The most famous case is the rim of the magnificent crater Aristarchus, which William Herschel, the father of modem astronomy, once observed shining so brightly in the lunar night that he decided it must be an active volcano. He was wrong; what he saw was the Earthlight reflected from a thin and transient layer of frost, condensed during the three hundred hours of freezing darkness.
   The discovery of the great ice deposits beneath Schroter's Valley, the sinuous canyon winding away from Anstarchus, was the last factor in the equation that would transform the economics of space-flight. The Moon could provide a filling station just where it was needed, high up on the outermost slopes of the Earth's gravitational field, at the beginning of the long haul to the planets.
   Cosmos, first of the Tsung fleet, had been designed to carry freight and passengers on the Earth-Moon-Mars run, and as a test-vehicle, through complex deals with a dozen organizations and governments, of the still experimental muon drive. Built at the Imbriurn shipyards, she had just sufficient thrust to lift off from the Moon with zero payload; operating from orbit to orbit, she would never again touch the surface of any world. With his usual flair for publicity, Sir Lawrence arranged for her maiden flight to commence on the hundredth anniversary of Sputnik Day, 4 October 2057.
   Two years later, Cosmos was joined by a sister ship. Galaxy was designed for the Earth-Jupiter run, and had enough thrust to operate directly to any of the Jovian moons, though at considerable sacrifice of payload. If necessary, she could even return to her lunar berth for refitting. She was by far the swiftest vehicle ever built by man: if she burned up her entire propellant mass in one orgasm of acceleration, she would attain a speed of a thousand kilometres a second – which would take her from Earth to Jupiter in a week, and to the nearest star in not much more than ten thousand years.
   The third ship of the fleet – and Sir Lawrence's pride and joy – embodied all that had been learned in the building of her two sisters. But Universe was not intended primarily for freight. She was designed from the beginning as the first passenger liner to cruise the space lanes – right out to Saturn, the jewel of the Solar System.
   Sir Lawrence had planned something even more spectacular for her maiden voyage, but construction delays caused by a dispute with the Lunar Chapter of the Reformed Teamsters' Union had upset his schedule. There would just be time for the initial flight tests and Lloyd's certification in the closing months of 2060, before Universe left Earth orbit for her rendezvous. It would be a very close thing: Halley's Comet would not wait, even for Sir Lawrence Tsung.

9 – Mount Zeus

   The survey satellite Europa VI had been in orbit for almost fifteen years, and had far exceeded its design life; whether it should be replaced was a subject of considerable debate in the small Ganymede scientific establishment.
   It carried the usual collection of data-gathering instruments, as well as a now virtually useless imaging system. Though still in perfect working order, all that this normally showed of Europa was an unbroken cloudscape. The overworked science team on Ganymede scanned the recordings in 'Quick Look' mode once a week, then squirted the raw data back to Earth. On the whole, they would be rather relieved when Europa VI expired and its torrent of uninteresting gigabytes finally dried up.
   Now, for the first time in years, it had produced something exciting.
   'Orbit 71934,' said the Deputy Chief Astronomer, who had called van der Berg as soon as the latest data-dump had been evaluated. 'Coming in from the nightside – heading straight for Mount Zeus. You won't see anything for another ten seconds, though.'
   The screen was completely black, yet van der Berg could imagine the frozen landscape rolling past beneath its blanket of clouds a thousand kilometres below. In a few hours the distant Sun would be shining there, for Europa revolved on its axis once in every seven Earth-days. 'Nightside' should really be called 'Twilight-side', for half the time it had ample light – but no heat. Yet the inaccurate name had stuck, because it had emotional validity: Europa knew Sunrise, but never Lucifer-rise.
   And the Sunrise was coming now, speeded up a thousandfold by the racing probe. A faintly luminous band bisected the screen, as the horizon emerged from darkness.
   The explosion of light was so sudden that van der Berg could almost imagine he was looking into the glare of an atomic bomb. In a fraction of a second, it ran through all the colours of the rainbow, then became pure white as the Sun leapt above the mountain – then vanished as the automatic filters cut into the circuit.
   'That's all; pity there was no operator on duty at the time – he could have panned the camera down and had a good view of the mountain as we went over. But I knew you'd like to see it – even though it disproves your theory.'
   'How?' said van der Berg, more puzzled than annoyed.
   'When you go through it in slow motion, you'll see what I mean. Those beautiful rainbow effects – they're not atmospheric – they're caused by the mountain itself. Only ice could do that. Or glass – which doesn't seem very likely.'
   'Not impossible – volcanoes can produce natural glass – but it's usually black... of course!'
   'Yes?'
   'Er – I won't commit myself until I've been through the data. But my guess would be rock crystal – transparent quartz. You can make beautiful prisms and lenses out of it. Any chance of some more observations?'
   'I'm afraid not – that was pure luck – Sun, mountain, camera all lined up at the right time. It won't happen again in a thousand years.'
   'Thanks, anyway – can you send me over a copy? No hurry – I'm just leaving on a field trip to Perrine, and won't be able to look at it until I get back.'
   Van der Berg gave a short, rather apologetic laugh.
   'You know, if that really is rock crystal, it would be worth a fortune. Might even help solve our balance of payments problem...'
   But that, of course, was utter fantasy. Whatever wonders – or treasures – Europa might conceal, the human race had been forbidden access to them, by that last message from Discovery. Fifty years later, there was no sign that the interdiction would ever be lifted

10 – Ship of Fools

   For the first forty-eight hours of the voyage, Heywood Floyd could not really believe the comfort, the spaciousness – the sheer extravagance of Universe's living arrangements. Yet most of his fellow passengers took them for granted; those who had never left Earth before assumed that all spaceships must be like this.
   He had to look back at the history of aeronautics to put matters in the right perspective. In his own lifetime, he had witnessed – indeed, experienced – the revolution that had occurred in the skies of the planet now dwindling behind him. Between the clumsy old Leonov and the sophisticated Universe lay exactly fifty years. (Emotionally, he couldn't really believe that – but it was useless arguing about arithmetic.)
   And just fifty years had separated the Wright Brothers from the first jet airliners. At the beginning of that half-century, intrepid aviators had hopped from field to field, begoggled and windswept on open chairs; at its end, grandmothers had slumbered peacefully between continents at a thousand kilometres an hour.
   So he should not, perhaps, have been astonished at the luxury and elegant decor of his stateroom, or even the fact that he had a steward to keep it tidy. The generously sized window was the most startling feature of his suite, and at first he felt quite uncomfortable thinking of the tons of air pressure it was holding in check against the implacable, and never for a moment relaxing, vacuum of space.
   The biggest surprise, even though the advance literature should have prepared him for it, was the presence of gravity. Universe was the first spaceship ever built to cruise under continuous acceleration, except for the few hours of the mid-course 'turnaround'. When her huge propellant tanks were fully loaded with their five thousand tons of water, she could manage a tenth of a gee – not much, but enough to keep loose objects from drifting around. This was particularly convenient at mealtimes – though it took a few days for the passengers to learn not to stir their soup too vigorously.
   Forty-eight hours out from Earth, the population of Universe had already stratified itself into four distinct classes.
   The aristocracy consisted of Captain Smith and his officers. Next came the passengers; then crew – non-commissioned and stewards. And then steerage...
   That was the description that the five young space scientists had adopted for themselves, first as a joke but later with a certain amount of bitterness. When Hoyd compared their cramped and jury-rigged quarters with his own luxurious cabin, he could see their point of view, and soon became the conduit of their complaints to the Captain.
   Yet all things considered, they had little to grumble about; in the rush to get the ship ready, it had been touch and go as to whether there would be any accommodation for them and their equipment. Now they could look forward to deploying instruments around – and on – the comet during the critical days before it rounded the Sun, and departed once more to the outer reaches of the Solar System. The members of the science team would establish their reputations on this voyage, and knew it. Only in moments of exhaustion, or fury with misbehaving instrumentation, did they start complaining about the noisy ventilating system, the claustrophobic cabins, and occasional strange smells of unknown origin.
   But never the food, which everyone agreed was excellent. 'Much better,' Captain Smith assured them, 'than Darwin had on the Beagle.'
   To which Victor Willis had promptly retorted:
   'How does he know? And by the way, Beagle's commander cut his throat when he got back to England.'
   That was rather typical of Victor, perhaps the planet's best-known science communicator – to his fans – or 'pop-scientist' – to his equally numerous detractors. It would be unfair to call them enemies; admiration for his talents was universal, if occasionally grudging. His soft, mid-Pacific accent and expansive gestures on camera were widely parodied, and he had been credited (or blamed) for the revival of full-length beards. 'A man who grows that much hair,' critics were fond of saying, 'must have a lot to hide.'
   He was certainly the most instantly recognizable of the six VIPs – though Floyd, who no longer regarded himself as a celebrity, always referred to them ironically as 'The Famous Five'. Yva Merlin could often walk unrecognized on Park Avenue, on the rare occasions when she emerged from her apartment. Dimitri Mihailovich, to his considerable annoyance, was a good ten centimetres below average height; this might help to explain his fondness for thousand-piece orchestras – real or synthesized -but did not enhance his public image.
   Clifford Greenburg and Margaret M'Bala also fell into the category of 'famous unknowns' – though this would certainly change when they got back to Earth. The first man to land on Mercury had one of those pleasant, unremarkable faces that are very hard to remember; moreover the days when he had dominated the news were now thirty years in the past. And like most authors who are not addicted to talk shows and autographing sessions, Ms M'Bala would be unrecognized by the vast majority of her millions of readers.
   Her literary fame had been one of the sensations of the forties. A scholarly study of the Greek pantheon was not usually a candidate for the best-seller lists, but Ms M'Bala had placed its eternally inexhaustible myths in a contemporary space-age setting. Names which a century earlier had been familiar only to astronomers and classical scholars were now part of every educated person's world picture; almost every day there would be news from Ganymede, Callisto, Io, Titan, Japetus – or even more obscure worlds like Carme, Pasiphaë, Hyperion, Phoebe...
   Her book would have been no more than modestly successful, however, had she not focused on the complicated family life of Jupiter-Zeus, Father of all the Gods (as well as much else). And by a stroke of luck, an editor of genius had changed her original title, The View from Olympus, to The Passions of the Gods. Envious academics usually referred to it as Olympic Lusts, but invariably wished they had written it.
   Not surprisingly, it was Maggie M – as she was quickly christened by her fellow passengers – who first used the phrase Ship of Fools. Victor Willis adopted it eagerly, and soon discovered an intriguing historical resonance. Almost a century ago, Katherine Anne Porter had herself sailed with a group of scientists and writers aboard an ocean liner to watch the launch of Apollo 17, and the end of the first phase of lunar exploration.
   'I'll think about it,' Ms M'Bala had remarked ominously, when this was reported to her. 'Perhaps it's time for a third version. But I won't know, of course, until we get back to Earth...'

11 – The Lie

   It was many months before Rolf van der Berg could once again turn his thoughts and energies towards Mount Zeus. The taming of Ganymede was a more than full-time job, and he was away from his main office at Dardanus Base for weeks at a time, surveying the route of the proposed Gilgamesh-Osiris monorail.
   The geography of the third and largest Galilean moon had changed drastically since the detonation of Jupiter – and it was still changing. The new sun that had melted the ice of Europa was not as powerful here, four hundred thousand kilometres further out – but it was warm enough to produce a temperate climate at the centre of the face forever turned towards it. There were small, shallow seas – some as large as Earth's Mediterranean – up to latitudes forty north and south. Not many features still survived from the maps generated by the Voyager missions back in the twentieth century. Melting permafrost and occasional tectonic movements triggered by the same tidal forces operating on the two inner moons made the new Ganymede a cartographer's nightmare.
   But those very factors also made it a planetary engineer's paradise. Here was the only world, except for the arid and much less hospitable Mars, on which men might one day walk unprotected beneath an open sky. Ganymede had ample water, all the chemicals of life, and – at least while Lucifer shone – a warmer climate than much of Earth.
   Best of all, full-body spacesuits were no longer necessary; the atmosphere, though still unbreathable, was just dense enough to permit the use of simple face-masks and oxygen cylinders. In a few decades – so the microbiologists promised, though they were hazy about specific dates – even these could be discarded. Strains of oxygen-generating bacteria had already been let loose across the face of Ganymede; most had died but some had flourished, and the slowly rising curve on the atmospheric analysis chart was the first exhibit proudly displayed to all visitors at Dardanus.
   For a long time, van der Berg kept a watchful eye on the data flowing in from Europa VI, hoping that one day the clouds would clear again when it was orbiting above Mount Zeus. He knew that the odds were against it, but while the slightest chance existed he made no effort to explore any other avenue of research. There was no hurry, he had far more important work on his hands – and anyway, the explanation might turn out to be something quite trivial and uninteresting.
   Then Europa VI suddenly expired, almost certainly as a result of a random meteoric impact. Back on Earth, Victor Willis had made rather a fool of himself – in the opinion of many – by interviewing the 'Euronuts' who now more than adequately filled the gap left by the UFO-enthusiasts of the previous century. Some of them argued that the probe's demise was due to hostile action from the world below: the fact that it had been allowed to operate without interference for fifteen years – almost twice its design life – did not bother them in the least. To Victor's credit, he stressed this point and demolished most of the cultists' other arguments; but the consensus was that he should never have given them publicity in the first place.
   To van der Berg, who quite relished his colleagues' description of him as a 'stubborn Dutchman' and did his best to live up to it, the failure of Europa VI was a challenge not to be resisted. There was not the slightest hope of funding a replacement, for the silencing of the garrulous and embarrassingly long-lived probe had been received with considerable relief.
   So what was the alternative? Van der Berg sat down to consider his options. Because he was a geologist, and not an astrophysicist, it was several days before he suddenly realized that the answer had been staring him in the face ever since he had landed on Ganymede.
   Afrikaans is one of the world's best languages in which to curse; even when spoken politely, it can bruise innocent bystanders. Van der Berg let off steam for a few minutes; then he put through a call to the Tiamat Observatory – sitting precisely on the equator, with the tiny, blinding disc of Lucifer forever vertically overhead.

   Astrophysicists, concerned with the most spectacular objects in the Universe, tend to patronize mere geologists who devote their lives to small, messy things like planets. But out here on the frontier, everyone helped everyone else, and Dr Wilkins was not only interested but sympathetic.
   The Tiamat Observatory had been built for a single purpose, which had indeed been one of the main reasons for establishing a base on Ganymede. The study of Lucifer was of enormous importance not only to pure scientists but also to nuclear engineers, meteorologists, oceanographers – and, not least, to statesmen and philosophers. That there were entities which could turn a planet into a sun was a staggering thought, and had kept many awake at night. It would be well for mankind to learn all it could about the process; one day there might be need to imitate it – or prevent it.
   And so for more than a decade Tiamat had been observing Lucifer with every possible type of instrumentation, continually recording its spectrum across the entire electromagnetic band, and also actively probing it with radar from a modest hundred-metre dish, slung across a small impact crater.
   'Yes,' said Dr Wilkins, 'we've often looked at Europa and Io. But our beam is fixed on Lucifer, so we can only see them for a few minutes while they're in transit. And your Mount Zeus is just on the dayside, so it's hidden from us then.'
   'I realize that,' said van der Berg a little impatiently. 'But couldn't you offset the beam by just a little, so you could have a look at Europa before it comes in line? Ten or twenty degrees would get you far enough into dayside.'
   'One degree would be enough to miss Lucifer, and get Europa full-face on the other side of its orbit. But then it would be more than three times further away, so we'd only have a hundredth of the reflected power. Might work, though: we'll give it a try. Let me have the specs on frequencies, wave envelopes, polarization and anything else your remote-sensing people think will help. It won't take us long to rig up a phase-shifting network that will slew the beam a couple of degrees. More than that I don't know – it's not a problem we've ever considered. Though perhaps we should have done so – anyway, what do you expect to find on Europa, except ice and water?'
   'If I knew,' said van der Berg cheerfully, 'I wouldn't be asking for help, would I?'
   'And I wouldn't be asking for full credit when you publish. Too bad my name's at the end of the alphabet; you'll be ahead of me by only one letter.'
   That was a year ago: the long-range scans hadn't been good enough, and offsetting the beam to look on to Europa's dayside just before conjunction had proved more difficult than expected. But at last the results were in; the computers had digested them, and van der Berg was the first human being to look at a mineralogical map of post-Lucifer Europa.
   It was, as Dr Wilkins had surmised, mostly ice and water, with outcroppings of basalt interspersed with deposits of sulphur. But there were two anomalies.
   One appeared to be an artefact of the imaging process; there was an absolutely straight feature, two kilometres long, which showed virtually no radar echo. Van der Berg left Dr Wilkins to puzzle over that; he was only concerned with Mount Zeus.
   It had taken him a long time to make the identification, because only a madman – or a really desperate scientist – would have dreamed that such a thing was possible. Even now, though every parameter checked to the limits of accuracy, he still could not really believe it. And he had not even attempted to consider his next move.
   When Dr Wilkins called, anxious to see his name and reputation spreading through the data banks, he mumbled that he was still analysing the results. But at last he could put it off no longer.
   'Nothing very exciting,' he told his unsuspecting colleague. 'Merely a rare form of quartz – I'm still trying to match it from Earth samples.'
   It was the first time he had ever lied to a fellow scientist, and he felt terrible about it.
   But what was the alternative?

12 – Oom Paul

   Rolf van der Berg had not seen his Uncle Paul for a decade, and it was not likely that they would ever again meet in the flesh. Yet he felt very close to the old scientist – the last of his generation, and the only one who could recall (when he wished, which was seldom) his forefathers' way of life.
   Dr Paul Kreuger – 'Oom Paul' to all his family and most of his friends – was always there when he was needed, with information and advice, either in person or at the end of a half-billion-kilometre radio link. Rumour had it that only extreme political pressure had forced the Nobel Committee – with great reluctance – to overlook his contributions to particle physics, now once more in desperate disarray after the general house-cleaning at the end of the twentieth century.
   If this was true, Dr Kreuger bore no grudge. Modest and unassuming, he had no personal enemies, even among the cantankerous factions of his fellow exiles. Indeed, he was so universally respected that he had received several invitations to re-visit the United States of Southern Africa, but had always politely declined – not, he hastened to explain, because he felt he would be in any physical danger in the USSA, but because he feared that the sense of nostalgia would be overwhelming.

   Even using the security of a language now understood by less than a million people, van der Berg had been very discreet, and had used circumlocutions and references that would be meaningless except to a close relative. But Paul had no difficulty in understanding his nephew's message, though he could not take it seriously. He was afraid young Rolf had made a fool of himself, and would let him down as gently as possible. Just as well he hadn't rushed to publish: at least he had the sense to keep quiet...

   And suppose – just suppose – it was true? The scanty hairs rose on the back of Paul's head. A whole spectrum of possibilities – scientific, financial, political – suddenly opened up before his eyes, and the more he considered them, the more awesome they appeared.
   Unlike his devout ancestors, Dr Kreuger had no God to address in moments of crisis or perplexity. Now, he almost wished he had; but even if he could pray, that wouldn't really help. As he sat down at his computer and started to access the data banks, he did not know whether to hope that his nephew had made a stupendous discovery – or was talking utter nonsense. Could the Old One really play such an incredible trick on mankind? Paul remembered Einstein's famous comment that though He was subtle, He was never malicious.
   Stop daydreaming, Dr Paul Kreuger told himself. Your likes or dislikes, your hopes or fears, have absolutely nothing to do with the matter.
   A challenge had been flung to him across half the width of the Solar System; he would not know peace until he had uncovered the truth.

13 – 'No-one told us to bring swimsuits...'

   Captain Smith kept his little surprise until day five, just a few hours before turnaround. His announcement was received, as he had expected, with stunned incredulity.
   Victor Willis was the first to recover.
   'A swimming pool! In a spaceship! You must be joking!'
   The Captain leaned back and prepared to enjoy himself. He grinned at Heywood Floyd who had already been let into the secret.
   'Well, I suppose Columbus would have been amazed at some of the facilities on the ships that came after him.'
   'Is there a diving board?' asked Greenburg wistfully. 'I used to be college champion.'
   'As a matter of fact – yes. It's only five metres – but that will give you three seconds of free fall, at our nominal tenth of a gee. And if you want a longer time, I'm sure Mr Curtis will be happy to reduce thrust.'
   'Indeed?' said the Chief Engineer dryly. 'And mess up all my orbit calculations? Not to mention the risk of the water crawling out, Surface tension, you know...
   'Wasn't there a space station once that had a spherical swimming pool?' somebody asked.
   'They tried it at the hub of Pasteur, before they started the spin,' answered Floyd. 'It just wasn't practical. In zero gravity, it had to be completely enclosed. And you could drown rather easily inside a big sphere of water, if you panicked.'
   'One way of getting into the record books – first person to drown in space...'
   'No-one told us to bring swimsuits,' complained Maggie M'Bala.
   'Anyone who has to wear a swimsuit probably should,' Mihailovich whispered to Floyd.
   Captain Smith rapped on the table to restore order. 'This is more important, please. As you know, at midnight we reach maximum speed, and have to start braking. So the drive will shut down at 23.00, and the ship will be reversed. We'll have two hours of weightlessness before we commence thrust again at 01.00.
   'As you can imagine, the crew will be rather busy – we'll use the opportunity for an engine check and a hull inspection, which can't be done while we're under power. I strongly advise you to be sleeping then, with the restraint straps lightly fastened across your beds. The stewards will check that there aren't any loose articles that could cause trouble when weight comes on again. Questions?'
   There was a profound silence, as if the assembled passengers were still somewhat stunned by the revelation and were deciding what to do about it.
   'I was hoping you'd ask me about the economics of such a luxury – but as you haven't, I'll tell you anyway. It's not a luxury at all – it doesn't cost a thing, but we hope it will be a very valuable asset on future voyages.
   'You see, we have to carry five thousand tons of water as reaction mass, so we might as well make the best use of it. Number One tank is now three-quarters empty; we'll keep it that way until the end of the voyage. So after breakfast tomorrow – see you down at the beach...

   Considering the rush to get Universe spaceborne, it was surprising that such a good job had been done on something so spectacularly non-essential.
   The 'beach' was a metal platform, about five metres wide, curving around a third of the great tank's circumference. Although the far wall was only another twenty metres away, clever use of projected images made it seem at infinity. Borne on the waves in the middle distance, surfers were heading towards a shore which they would never reach, Beyond them, a beautiful passenger clipper which any travel agent would recognize instantly as Tsung Sea-Space Corporation's Tai-Pan was racing along the horizon under a full spread of sail.
   To complete the illusion, there was sand underfoot (slightly magnetized, so it would not stray too far from its appointed place) and the short length of beach ended in a grove of palm trees which were quite convincing, until examined too closely. Overhead, a hot tropical sun completed the idyllic picture; it was hard to realize that just beyond these walls the real Sun was shining, now twice as fiercely as on any terrestrial beach.
   The designer had really done a wonderful job, in the limited space available. It seemed a little unfair of Greenburg to complain: 'Pity there's no surf...'

14 – Search

   It is a good principle in science not to believe any 'fact' – however well-attested – until it fits into some accepted frame of reference. Occasionally, of course, an observation can shatter the frame and force the construction of a new one, but that is extremely rare. Galileos and Einsteins seldom appear more than once per century, which is just as well for the equanimity of mankind.
   Dr Kreuger fully accepted this principle: he would not believe his nephew's discovery until he could explain it, and as far as he could see that required nothing less than a direct Act of God. Wielding Occam's still highly serviceable razor, he thought it somewhat more probable that Rolf had made a mistake; if so, it should be fairly easy to find it.
   To Uncle Paul's great surprise, it proved very difficult indeed. The analysis of radar remote-sensing observations was now a venerable and well-established art, and the experts that Paul consulted all gave the same answer, after considerable delay. They also asked: 'Where did you get that recording?'
   'Sorry,' he had answered. 'I'm not at liberty to say.'
   The next step was to assume that the impossible was correct, and to start searching the literature. This could be an enormous job, for he did not even know where to begin. One thing was quite certain: a brute-force, head-on attack was bound to fail. It would be just as if Roentgen, the morning after he had discovered X-rays, had started to hunt for their explanation in the physics journals of his day. The information he needed still lay years in the future.
   But there was at least a sporting chance that what he was looking for was hidden somewhere in the immense body of existing scientific knowledge. Slowly and carefully, Paul Kreuger set up an automatic search programme, designed for what it would exclude as much as what it would embrace. It should cut out all Earth-related references – they would certainly number in the millions – and concentrate entirely on extraterrestrial citations.
   One of the benefits of Dr Kreuger's eminence was an unlimited computer budget: that was part of the fee he demanded from the various organizations who needed his wisdom. Though this search might be expensive, he did not have to worry about the bill.
   As it turned out, this was surprisingly small. He was lucky: the search came to an end after only two hours thirty-seven minutes, at the 21,456th reference.
   The title was enough. Paul was so excited that his own comsec refused to recognize his voice, and he had to repeat the command for a full print-out.
   Nature had published the paper in 1981 – almost five years before he was born! – and as his eyes swept swiftly over its single page he knew not only that his nephew had been right all along – but, just as important, exactly how such a miracle could occur.
   The editor of that eighty-year-old journal must have had a good sense of humour. A paper discussing the cores of the outer planets was not something to grab the usual reader: this one, however, had an unusually striking title. His comsec could have told him quickly enough that it had once been part of a famous song, but that of course was quite irrelevant.
   Anyway, Paul Kreuger had never heard of the Beatles, and their psychedelic fantasies.

II – THE VALLEY OF THE BLACK SNOW

15 – Rendezvous

   And now Halley was too close to be seen; ironically, observers back on Earth would get a far better view of the tail, already stretching fifty million kilometres at right angles to the comet's orbit, like a pennant fluttering in the invisible gale of the solar wind.
   On the morning of the rendezvous, Heywood Floyd woke early from a troubled sleep. It was unusual for him to dream – or at least to remember his dreams – and doubtless the anticipated excitements of the next few hours were responsible. He was also slightly worried by a message from Caroline, asking if he had heard from Chris lately. He had radioed back, a little tersely, that Chris had never bothered to say thank you when he had helped him get his current position on Universe's sister ship Cosmos; perhaps he was already bored with the Earth-Moon run and was looking for excitement elsewhere.
   'As usual,' Floyd had added, 'we'll hear from him in his own good time.'
   Immediately after breakfast, passengers and science team had gathered for a final briefing from Captain Smith. The scientists certainly did not need it, but if they felt any irritation, so childish an emotion would have been quickly swept away by the weird spectacle on the main viewscreen.
   It was easier to imagine that Universe was flying into a nebula, rather than a comet. The entire sky ahead was now a misty white fog – not uniform, but mottled with darker condensations and streaked with luminous bands and brightly glowing jets, all radiating away from a central point. At this magnification, the nucleus was barely visible as a tiny black speck, yet it was clearly the source of all the phenomena around it.
   'We cut our drive in three hours,' said the Captain. 'Then we'll be only a thousand kilometres away from the nucleus, with virtually zero velocity. We'll make some final observations, and confirm our landing site.'
   'So we'll go weightless at 12.00 exactly. Before then, your cabin stewards will check that everything's correctly stowed. It will be just like turnaround, except that this time it's going to be three days, not two hours, before we have weight again.
   'Halley's gravity? Forget it – less than one centimetre per second squared – just about a thousandth of Earth's. You'll be able to detect it if you wait long enough, but that's all. Takes fifteen seconds for something to fall a metre.
   'For safety, I'd like you all here in the observation lounge, with your seat belts properly secured, during rendezvous and touchdown. You'll get the best view from here anyway, and the whole operation won't take more than an hour. We'll only be using very small thrust corrections, but they may come from any angle and could cause minor sensory disturbances.'
   What the Captain meant, of course, was spacesickness – but that word, by general agreement, was taboo aboard Universe. It was noticeable, however, that many hands strayed into the compartments beneath the seats, as if checking that the notorious plastic bags would be available if urgently required.
   The image on the viewscreen expanded, as the magnification was increased. For a moment it seemed to Floyd that he was in an aeroplane, descending through light clouds, rather than in a spacecraft approaching the most famous of all comets. The nucleus was growing larger and clearer; it was no longer a black dot, but an irregular ellipse – now a small, pockmarked island lost in the cosmic ocean – then, suddenly, a world in its own right.
   There was still no sense of scale. Although Floyd knew that the whole panorama spread before him was less than ten kilometres across, he could easily have imagined that he was looking at a body as large as the Moon. But the Moon was not hazy around the edges, nor did it have little jets of vapour – and two large ones – spurting from its surface.
   'My God!' cried Mihailovich, 'what's that?'
   He pointed to the lower edge of the nucleus, just inside the terminator. Unmistakably – impossibly -a light was flashing there on the nightside of the comet with a perfectly regular rhythm: on, off, on, off, once every two or three seconds.
   Dr Willis gave his patient 'I can explain it to you in words of one syllable' cough, but Captain Smith got there first.
   'I'm sorry to disappoint you, Mr Mihailovich. That's only the beacon on Sampler Probe Two – it's been sitting there for a month, waiting for us to come and pick it up.'
   'What a shame; I thought there might be someone – something – there to welcome us.'
   'No such luck, I'm afraid; we're very much on our own out here. That beacon is just where we intend to land – it's near Halley's south pole and is in permanent darkness at the moment. That will make it easier on our life-support systems. The temperature's up to 120 degrees on the Sunlit side – way above boiling point.'
   'No wonder the comet's perking,' said the unabashed Dimitri. 'Those jets don't look very healthy to me. Are you sure it's safe to go in?'
   'That's another reason we're touching down on the nightside; there's no activity there. Now, if you'll excuse me, I must get back to the bridge. This is the first chance I've ever had of landing on a new world – and I doubt if I'll get another.'
   Captain Smith's audience dispersed slowly, and in unusual silence. The image on the viewscreen zoomed back to normal, and the nucleus dwindled once more to a barely visible spot. Yet even in those few minutes it seemed to have grown slightly larger, and perhaps that was no illusion. Less than four hours before encounter, the ship was still hurtling towards the comet at fifty thousand kilometres an hour.
   It would make a crater more impressive than any that Halley now boasted, if something happened to the main drive at this stage of the game.