Which, in this case, was not very many. Apart from any other consideration, the proto-Wan-To hadn't been very smart then—well, he had been an infant, after all! His entire network had hardly amounted to more than two or three hundred billion particles altogether, and none of them fully integrated with the others as yet. But as he had grown over the eons to be very smart indeed, and, quite curious, he had spent a lot of thought in deducing how that event had had to be.
As his galaxy (the old one, the one Wan-To had left when it became uninhabitable) turned on its axis, the leading edge of one of its spiral arms passed through a "density wave," and a patch of ionized gases was compressed by the shock of contact.
That was just the beginning. It didn't create Wan-To's predecessor. It only made it possible for the next nearby event to do so.
That event came when a particular star of a rather rare kind came to the end of its hydrogen-burning life. It had been a very large star, so it used up its hydrogen quite quickly. Then, with most of its hydrogen turned into helium, it was running out of its best fusion fuel and destined for trouble.
The star could, to be sure, go on burning the helium into heavier elements still. But it took four hydrogen nuclei to make one helium, so when you got down to helium there was only a quarter as much fuel to begin with. Worse than that, helium burning doesn't yield as much energy. Energy was what that old star was beginning to run out of. Energy was what it needed to keep its shape, because it was only the pressure of the terrible heat from within that kept the immense pressure of its outer layers from collapsing into its core.
When the energy from the hydrogen at last ran out, it did collapse.
All that vast mass dropped—"like a stone," a human being might say, but much faster, and with far vaster impact, than any stone ever dropped on Earth. It struck the core, squeezing it from all directions at once. The core rebounded. Four-fifths of the mass of the star blasted itself into space in that great bursting, with floods of X rays and gammas and neutrinos, as well as ten-million-million-degree heat and blinding light; and as that furiously energetic mass raced through space it struck the already compacted mass of gas that was the womb that held the not-yet-existent precursor of Wan-To.
That was what Earthly astronomers would have called a "supernova." The humans, too, had wondered about how things began, and they had worked out that their own sun and most others had been born in that way. They rarely saw a real supernova, of course—especially not one in their own galaxy—because human beings didn't live long enough for that. But they knew that such events happened, over and over, hundreds of millions of times in each galaxy.
They did not, however, ordinarily give rise to anything like a Wan-To.
The supernova that gave birth to Wan-To's forebear was not any ordinary Type I or Type II. It was of the rare kind Earthly astronomers had named an "Urtrobin supernova," after the Soviet astronomer who had found the first of its kind in an obscure galaxy in the constellation Perseus. Urtrobin supernovae don't start with any ordinary supergiant star, a mere twenty or a hundred times as massive as the Earth's sun. What is required for an Urtrobin supernova is that very rare celestial object, a star that masses as much as two thousand suns put together.
There aren't many stars like that. A lot of Earthly astronomers refused to believe that any such overbloated body could ever form—at least, they refused until they began to calculate in the relativistic effects and saw that those did in fact make it possible. But when such a supermassive star collapses its explosion does not last for a mere matter of months. It takes as much as a year for it to reach peak brightness. Then it declines to obscurity only over a period of decades.
It was in just such a godlike hammer blow that Wan-To's ancestor's wisp of gas was squeezed and drenched. It was enough. The ancestor was born.
Such an event, affecting such a scarce collection of ionized gases, was very rare indeed in the universe. There could not have been very many such beings formed, not in all the dozen billion years since the Big Bang.
Indeed, Wan-To would have thought his unfortunate parent had been very likely the only one … if he had not observed the wreck of some distant galaxies and realized that creatures like himself must have done the wrecking.
He did not want his present galaxy wrecked. It was such a chore to move.
CHAPTER 12
It was a long trip to Nebo, a hundred and twenty hard days, tough times for any small group of people locked into each other's company. For Viktor the trip was grim.
Black worry began creeping over him as soon as they pulled out of Low Newmanhome Orbit. It got worse. First it was the radio; the surprised, then frantic, then furious calls began to come in from the surface. It got worse still when his sister Edwina got on to plead with him, worst of all when she turned the microphone over to little Tanya. That was pretty close to heartbreaking, the sweet, worried little voice, begging. "Mommy? Daddy Jake? Daddy Viktor? Won't you please come home?" It sent Reesa fleeing into a dark and empty cargo compartment, and when Viktor found her she was weeping uncontrollably. Then she closed up, would hardly talk at all. Not just Reesa, either. Everyone was having second thoughts; everyone was in a touchy, grouchy mood. By the time Captain Rodericks had inserted Ark into its parking orbit around Nebo and the lander was stocked and ready to take a crew down to the surface, hardly anyone was speaking to anyone else.
In Viktor's black cloud of worry he kept turning their decision over and over in his mind, asking himself the same nagging questions. Did the kids really need them at home? Well, of course they did, but … And did the people need them there, for that matter? Wasn't it, maybe, their duty to be there, sharing whatever came of this unexpected, this unexplained new calamity that was (maybe) threatening the colony's very survival? Well, maybe that was so, but still …
But still what they were doing was necessary! They had to find out what was happening on Nebo! Didn't they?
And even if they didn't, if the whole thing was criminal folly, it was long too late to be asking any of those questions. They were committed.
The other part of Viktor's black cloud was the unhappy state of his relations with Reesa. Something had gone very wrong. In all those hundred and twenty days they did not make love once. True, there wasn't any privacy to speak of in the stripped-down ship. True, Captain Rodericks (who took as an article of faith that only a busy crew could possibly be a happy crew—however laughable it was to use the word "happy" in the present circumstances) had set up an elaborate routine of drills and practice emergencies, Captain Bu backing him up all the way, and everybody was exhausted most of the time. But Reesa hardly even talked to Viktor any more.
What made that particularly hard to accept was that there were people she did talk to, and one of them was Jake Lundy. So to all Viktor's doubts and discomforts there was added the thing he had never wanted to believe himself capable of. He was jealous.
Four people were to go down to the surface of Nebo in the ship's lander. No one volunteered. No one refused, either; they drew lots.
When Jake Lundy turned out to be one of the chosen ones—and Viktor and Reesa were not—Viktor didn't rejoice, exactly, but it certainly did not break his heart.