‘How dare I what?’ Pitt frowned.

‘How dare you order me out of here as though I were a computer-puncher? If I hadn't found Nemesis, we wouldn't be here. You wouldn't be Commissioner-elect. Nemesis is mine. I have a say in it.’

‘Nemesis isn't yours. It's Rotor's. So please leave now and let me get on with the business of the day.’

‘Janus,’ she said, raising her voice. ‘I tell you again that, in all likelihood, Nemesis is moving toward our Solar System.’

‘And I tell you again that it is only a fifty-fifty chance that it is. And even if it were heading toward the Solar System - not our Solar System any longer, by the way, but their Solar System - don't tell me it's going to hit the Sun. I won't believe you if you do. In its whole nearly five-billion-year history, the Sun has never been struck by a star, or even come close. The odds against stellar collisions even in relatively crowded parts of the Galaxy are enormous. I may not be an astronomer, but I know that much.’

‘Odds are just odds, Janus, not certainties. It's conceivable , however unlikely, that Nemesis and the Sun might collide, but I recognize that it's very unlikely they will. The trouble is that a close approach, even without collision, might be fatal to Earth.’

‘How close is a close approach?’

‘I don't know. It will take a great deal of computation.’

‘All right, then. You suggest that we take the trouble to make the necessary observations and computations and, if we find out that the situation is indeed fraught with danger to the Solar System, then what? Do we warn the Solar System?’

‘Well, yes. What choice would we have?’

‘And how would we warn them? We have no means of hypercomrnunication and, even if we had, they have no system for receiving hypermessages. If we sent out a luminal message of some sort - light, micro-waves, modulated neutrinos - it would take over two years to reach Earth, assuming we have a beam powerful enough, or sufficiently coherent. And even then, how would we know if they had received it? If they had and bothered to answer, that answer would take another two years to return. And what will be the final result of the warning? We will have to tell them where Nemesis is and they will see that the information is coming from that direction. The whole point of our secrecy, the whole plan for establishing a homogeneous civilization around Nemesis, free of interference, would be lost.’

‘Whatever the cost, Janus, how could you consider not warning them?’

‘Where's your concern? Even if Nemesis is moving toward the Sun, how long would it take for it to reach the Solar System?’

‘It could reach the neighborhood of the Sun in five thousand years.’

Pitt sat back in his chair and regarded Insigna with a kind of wry amusement. ‘Five thousand years. Only five thousand years? Look, Eugenia, two hundred and fifty years ago, the first Earthman stood on the Moon. Two and a half centuries have passed and here we are at the nearest star. Where will we be in another two and a half centuries, at this rate? At any star we wish. And in five thousand years, fifty centuries, we will be all over the Galaxy, barring the presence of other intelligent forms of life. We will be reaching out to other galaxies. Within five thousand years, technology will have advanced to the point where, if the Solar System were really in trouble, all its Settlements and its entire planetary population could take off for deep space and other stars.’

Insigna shook her head. ‘Don't think that technological advance means that you can empty the Solar System by a mere wave of the hand, Janus. To remove billions of people without chaos and without tremendous loss of life would require long preparation. If they are in mortal danger five thousand years from now, they must know now . It is not too soon to begin to plan.’

Pitt said, ‘You have a good heart, Eugenia, so I'll offer a compromise. Suppose we take a hundred years in which to establish ourselves here, to multiply, to build a cluster of Settlements that will be strong enough and stable enough to be secure. Then we can investigate Nemesis' destination and - if necessary - warn the Solar System. They will still have nearly five thousand years in which to prepare. Surely a small delay of a century will not be fatal.’

Insigna sighed. ‘Is that your vision of the future? Humanity squabbling endlessly over the stars? Each little group trying to establish itself as supreme over this star or that? Endless hatred, suspicion, and conflict, of the kind we had on Earth for thousands of years, expanded into the Galaxy for thousands more?’

‘Eugenia, I have no vision. Humanity will do as it pleases. It will squabble as you say, or it will perhaps set up a Galactic Empire, or do something else. I can't dictate what humanity will do, and I don't intend to try to shape it. For myself, I have only this one Settlement to care for, and this one century in which to establish it at Nemesis. By then, you and I will be safely dead, and our successors will handle the problem of warning the Solar System - if that should be necessary. I'm trying to be reasonable, not emotional, Eugenia. You are a reasonable person, too. Think about it.’

Insigna did. She sat there, looking somberly at Pitt, while he waited with almost exaggerated patience.

Finally she said, ‘Very well. I see your point. I will get on with analyzing Nemesis' motion relative to the Sun. Perhaps we can forget the whole thing.’

‘No.’ Pitt raised an admonishing finger. ‘Remember what I said earlier. These observations will not be made. If it turns out that the Solar System is not in danger, we will have gained nothing. We will then merely do what I insist we do in any case - spend a century strengthening the civilization of Rotor. If, however, you find that there is danger, then your conscience will hurt and you will be consumed with apprehensions and fears and guilt. The news will somehow get out and it will weaken the resolve of Rotorians, many of whom may be as sentimental as you are. We would then lose a great deal. Do you understand me?’

She was silent, and he said, ‘Good. I see you do.’ Again, the wave of his hand made it clear that she was to leave.

This time she left, and Pitt, looking after her, thought: She is really becoming insupportable.