host without particularly noticing the meal. Worse, if it remained inside Negrav, the asteroid would disappear entirely. Van Noon did not much fancy being known for the rest of his career as the man who lost a whole asteroid.
In an agony of indecision, he called for the orbit of the asteroid to be monitored continuously, while he searched through the ship’s stocks hoping to find sufficient explosive to kick the asteroid’s velocity up and bring the black hole again to the outside. A trip to New Australia for fresh supplies was out of the question because of the time involved. By the time they returned, Negrav would have been swallowed whole.
He was unlucky. The explosives he had brought from New Australia had been carefully calculated for the job, and the entire stock had been used. Nor did the ship carry any stocks of its own. He briefly thought of trying to nudge the asteroid with the ship itself, but concluded that the vessel was unlikely to survive the ordeal.
Disconsolate, he sat down again to check the results of the orbital monitoring. As he did so, he began to brighten considerably. When Jacko found him, he was chuckling uncontrollably, and tears of laughter were streaming down his face.
‘You’re the first person I ever saw get a belly-laugh out of a computer printout,’ said Jacko warily. ‘We don’t have a strait-jacket, so I’d better give you a shot of tranquillizer. I’d advise you not to struggle.’
‘Knock it off, Jacko! I’ve just received proof of the theorem that the deserving don’t always get what they deserve. Alternatively, the unorthodox looks after its own.’
‘Crazy like two foxes!’
‘Look at these orbital figures, Jacko. And tell me what it was about the original problem we forgot.’
Jacko took the sheets of printout and looked through them wonderingly. Then he, too, began to smile.
‘Negrav’s speeding up. If it continues to do that, the black hole’ll come outside again of its own accord— and soon.’
‘Right! We forgot about conservation of momentum. As the black hole removes some of Negrav’s mass, the asteroid gets lighter but its initial momentum remains. Therefore it has to go faster, and climb into a higher orbit. It’s a self-stabilizing system because whenever the black hole removes some mass from the asteroid, Negrav itself automatically retreats from the attack.’
‘So what’re we left with? The same problem only with a slightly smaller Negrav?’
‘No. Unless my figures are wrong, the black hole’s been in there long enough to give us a concentric ball and shell effect—like a marble in a table-tennis ball. The increase in Negrav’s speed is running up an exponential curve, so that when the black hole does come out it should do so at some considerable angle. With luck it’ll only puncture the shell as it comes, not eat it away. And do you realize the implications of
‘We were lucky?’ asked Jacko uncertainly.
‘Yes, but not only that. It means that Negrav will be safer from attack by the black hole than ever before. And if that cavity’s the size I think it is, they’ll be able to build a major base in there, not just an observatory. They can mine Leda at their leisure, and use Negrav as an on the spot refinery and transfer station from which they can load hyper ships direct. It’ll be the most valuable space facility on the Rim.’
As the figures had predicted, the black hole did come out of Negrav. It reappeared some thirty-two hours later and finally stabilized with an orbital separation of eleven kilometres. This new orbital distance was a measure of the amount of mass which had been removed from Negrav.
The next part of the exercise was to explore the cavity itself. This was aided by the fact that they could now anchor a structure permanently on to the surface to give them safe working conditions without fear of being eaten by the black hole. With this new facility, the work progressed rapidly. Twenty metres in, they broke into free space inside the asteroid. Van Noon was first through, followed by Jacko and an assemblage of powerful lamps. Once inside, they gazed into the vastness with amazement.
Fritz’s ball and shell concept was substantially true, but random deviations in the rotation of Negrav had not produced a completely clean cavity, but rather one populated here and there with crazy spires and towers and bridges, and many vast columns which rose up to support the central core nearly a kilometre above the inner surface. Every line was curved in representation of some complex mathematical equation, as though designed by a mammoth computer programmed to seek out the ultimate in form and shape; and everything was cleanly cut and polished in flawless nickel iron alloy.
They made a tour of inspection which lasted nearly twelve hours, and came out so impressed with the wonder of it all that it was difficult to believe that these fantasies had been the results of interference with their own hands. As an STA base, the situation was, and would be always, without parallel. Had it not been situated on the Rim, it would have been a tourist attraction with no conceivable opposition. They had juggled precariously with Nature, and been rewarded with a marvellous demonstration of natural design that made them feel humbled and just a little bit afraid.
They found the points by which the black hole had entered and left the cavity, and had these sealed. Over their original entry point they built a docking hatch and an airlock. They then radioed New Australia for the STA to come and take possession of the prize. Captain-Administrator Wilson was the first STA man to arrive. He went in with a disbelieving sneer, and came out so passionately impressed that he couldn’t speak.
From then on, the more orthodox engineers took charge, ferrying gases to provide a breathable atmosphere in the cavity, bringing in power plants and treatment plants and all the paraphernalia necessary to support existence in the far reaches of space. Their task done, the unorthodox engineers returned in triumph back to Terra.
‘You don’t have to rub it in, Fritz,’ said Colonel Belling, when next they met. ‘I admit I was wrong and you were right. Unorthodoxy
‘Actually we’re only arguing about definitions,’ said Van Noon. ‘Orthodoxy for us is the tools and techniques which have been evolved for dealing with our local Terran situation. We can’t expect these to be the optimum for a completely altered set of conditions. What’s orthodox in one part of the galaxy may be unorthodox in another. All that I’m saying is that the most useful thing we can take to any problem is an open mind.’
‘Well you’ve certainly proved your point. The STA are so delighted with their acquisition that they’ve asked permission to call their Negrav installation Base Van Noon. I thought it only fair to let you make your own refusal.’
‘Refusal?’
‘That’s what I said, Fritz. While you’ve been journeying back, I’ve been analysing your figures. As I read it, this was a battle you actually lost, but were saved by a most fantastic stroke of luck. D’you really mean to claim it as a victory?’
‘In the circumstances, I take your point. But I claim the right to nominate my own alternative.’
‘Which is?’ asked Belling ominously.
‘How about Serendipity?’
The Colonel’s face broke into a smile. ‘I’ll go along with that, Fritz. I’ll even buy you a drink on it. And while you’re here, there’s another matter I want to discuss. It concerns the tunnelling problem on Eggar III. Now I’ve been thinking that if you can find another black hole…’
