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.'

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.