"Hello, Leonov," said Curnow at last. "Sorry to keep you waiting, but we've been rather busy."
"Here's a quick assessment, judging from what we've seen so far. The ship's in much better shape than I feared. Hull's intact, leakage negligible - air pressure eighty-five per cent nominal. Quite breathable, but we'll have to do a major recycling job because it stinks to high heaven.
"The best news is that the power systems are okay. Main reactor stable, batteries in good shape. Almost all the circuit-breakers were open - they'd jumped or been thrown by Bowman before he left - so all vital equipment's been safeguarded. But it will be a very big job checking everything before we have full power again."
"How long will that take - at least for the essential systems: life-support, propulsion?"
"Hard to say, skipper. How long before we crash?"
"Minimum present prediction is ten days. But you know how that's changed up - and down."
"Well, if we don't run into any major snags, we can haul Discovery up to a stable orbit away from this hellhole - oh, I'd say inside a week."
"Anything you need?"
"No - Max and I are doing fine. We're going into the carousel now, to check the bearings. I want to get it running as soon as possible."
"Pardon me, Walter - but is that important? Gravity's convenient, but we've managed without any for quite a while."
"I'm not after gravity, though it will be useful to have some aboard. If we can get the carousel running again, it will mop up the ship's spin - stop it tumbling. Then we'll be able to couple our airlocks together, and cut out EVAs. That will make work a hundred times easier."
"Nice idea, Walter - but you're not going to mate my ship to that... windmill. Suppose the bearings seize up and the carousel jams? That would tear us to pieces."
"Agreed. We'll cross that bridge when we come to it. I'll report again as soon as I can."
No one had much rest for the next two days. By the end of that time, Curnow and Brailovsky had practically fallen asleep in their suits, but had completed their survey of Discovery and found no unpleasant surprises. Both the Space Agency and the State Department were relieved by the preliminary report; it allowed them to claim, with some justification, that Discovery was not a derelict but a 'temporarily decommissioned United States Spacecraft'. Now the task of reconditioning had to begin.
Once power had been restored, the next problem was the air; even the most thorough housecleaning operations had failed to remove the stink. Curnow had been right in identifying its source as food spoiled when refrigeration had failed; he also claimed, with mock seriousness, that it was quite romantic. "I've only got to close my eyes," he asserted, "and I feel I'm back on an old-time whaling ship. Can you imagine what the Pequod must have smelled like?"
It was unanimously agreed that, after a visit to Discovery, very little effort of the imagination was required. The problem was finally solved - or at least reduced to manageable proportions - by dumping the ship's atmosphere. Fortunately, there was still enough air in the reserve tanks to replace it.
One piece of very welcome news was that ninety per cent of the propellant needed for the return journey was still available; choosing ammonia instead of hydrogen as working fluid for the plasma drive had paid off handsomely. The more efficient hydrogen would have boiled off into space years ago, despite the insulation of the tanks and the frigid temperature outside. But almost all the ammonia had remained safely liquified, and there was enough to get the ship back to a safe orbit around the Earth. Or at least around the Moon.
Checking Discovery's propellerlike spin was perhaps the most critical step in getting the ship under control. Sasha Kovalev compared Curnow and Brailovsky to Don Quixote and Sancho Panza, and expressed the hope that their windmill-tilting expedition would end more successfully.
Very cautiously, with many pauses for checking, power was fed to the carousel motors and the great drum was brought up to speed, reabsorbing the spin it had long ago imparted to the ship. Discovery executed a complex series of precessions, until eventually its end-over-end tumble had almost vanished. The last traces of unwanted rotation were neutralized by the attitude-control jets, until the two ships were floating motionless side by side, the squat, stocky Leonov dwarfed by the long, slender Discovery.
Transfer from one to the other was now safe and easy, but Captain Orlova still refused to permit a physical linkup. Everyone agreed with this decision, for Io was coming steadily closer; they might yet have to abandon the vessel they had worked so hard to save.
The fact that they now knew the reason for Discovery's mysterious orbital decay did not help in the least. Every time the ship passed between Jupiter and Io, it sliced through the invisible flux-tube linking the two bodies - the electric river flowing from world to world. The resulting eddy currents induced in the ship were continually slowing it down, braking it once every revolution.
There was no way to predict the final moment of impact, for the current in the flux-tube varied wildly according to Jupiter's own inscrutable laws. Sometimes there were dramatic surges of activity accompanied by spectacular electric and auroral storms around Io. Then the ships would lose altitude by many kilometres, at the same time becoming uncomfortably hot before their thermal control systems could readjust.
This unexpected effect had scared and surprised everyone before the obvious explanation was realized. Any form of braking produces heat, somewhere; the heavy currents induced in the hulls of Leonov and Discovery turned them briefly into low-powered electric furnaces. It was not surprising that some of Discovery's food supply had been ruined during the years the ship had been alternately cooked and cooled.
The festering landscape of Io, looking more than ever like an illustration from a medical textbook, was only five hundred kilometres away when Curnow risked activating the main drive, while Leonov stood off at a very respectful distance. There were no visible effects - none of the smoke and fire of the old-time chemical rockets - but the two ships drew slowly apart as Discovery gained speed. After a few hours of very gentle manoeuvring, both ships had raised themselves a thousand kilometres; now there was time to relax briefly, and to make plans for the next stage in the mission.
"You've done a wonderful job, Walter," said Surgeon-Commander Rudenko, putting her ample arm around the exhausted Curnow's shoulders. "We're all proud of you."
Very casually, she broke a small capsule under his nose. It was twenty-four hours before he woke up, annoyed and hungry.
20
Guillotine
What is it?" asked Curnow with mild distaste, hefting the little mechanism in his hand. "A guillotine for mice?"
"Not a bad description - but I'm after bigger game." Floyd pointed to a flashing arrow on the display screen, which was now showing a complicated circuit diagram.
"You see this line?"
"Yes - the main power supply. So?"
"This is the point where it enters Hal's central processing unit. I'd like you to install this gadget here. Inside the cable trunking, where it can't be found without a deliberate search."
"I see. A remote control, so you can pull the plug on Hal whenever you want to. Very neat - and a non-conducting blade, too, so there won't be any embarrassing shorts when it's triggered. Who makes toys like this? The CIA?"
"Never mind. The control's in my room - that little red calculator I always keep on my desk. Put in nine nines, take the square root, and press TNT. That's all. I'm not sure of its range - we'll have to test that - but as long as Leonov and Discovery are within a couple of kilometres of each other, there'll be no danger of Hal running amok again."
"Who are you going to tell about this... thing?"
"Well, the only person I'm really hiding it from is Chandra."
"I guessed as much."
"But the fewer who know, the less likely it is to be talked about. I'll tell Tanya that it exists, and if there's an emergency you can show her how to operate it."
"What kind of emergency?"
/> "That's not a very bright question, Walter. If I knew, I wouldn't need the damn thing."
"Guess you're right. When do you want me to install your patented Hal-zapper?"
"As soon as you can. Preferably tonight. When Chandra's sleeping."
"Are you kidding? I don't think he ever sleeps. He's like a mother nursing a sick baby."
"Well, he's got to come back to Leonov to eat, occasionally."
"I've news for you. The last time he went across, he tied a little sack of rice to his suit. That will keep him going for weeks."
"Then we'll have to use one of Katerina's famous knockout drops. They did a pretty good job on you, didn't they?"
Curnow was joking about Chandra - at least, Floyd assumed that he was, though one could never be quite sure: he was fond of making outrageous statements with a perfectly straight face. It had been some time before the Russians had fully realized that; soon, in self-defence, they were prone to pre-emptive laughs even when Curnow was being perfectly serious.
Curnow's own laugh, mercifully, had much abated since Floyd had first heard it in the upward-bound shuttle; on that occasion, it had obviously been primed by alcohol. He had fully expected to cringe from it again at the end-of-orbit party, when Leonov had finally made rendezvous with Discovery. But even on that occasion, though Curnow had drunk a good deal, he had remained as much under control as Captain Orlova herself.
The one thing he did take seriously was his work. On the way up from Earth, he had been a passenger. Now he was crew.
21
Resurrection
We are, Floyd told himself, about to awaken a sleeping giant. How will Hal react to our presence, after all these years? What will he remember of the past - and will he be friendly, or hostile?
As he floated just behind Dr Chandra in the zero-gravity environment of Discovery's flight deck, Floyd's mind was seldom far from the cut-off switch, installed and tested only a few hours earlier. The radio control was mere centimetres from his hand, and he felt somewhat foolish to have brought it with him. At this stage, Hal was still disconnected from all the ship's operational circuits. Even if he was reactivated, he would be a brain without limbs though not without sense organs. He would be able to communicate, but not to act. As Curnow had put it, "The worst he can do is swear at us."
"I'm ready for the first test, Captain," said Chandra. "All the missing modules have been replaced, and I've run diagnostic programs on all circuits. Everything appears normal, at least on this level."
Captain Orlova glanced at Floyd, who gave a nod. At Chandra's insistence, only the three of them were present for this critical first run, and it was quite obvious that even this small audience was unwelcome.
"Very well, Dr Chandra." Ever conscious of protocol, the captain added quickly: "Dr Floyd has given his approval, and I have no objections myself."
"I should explain," said Chandra, in a tone that clearly conveyed disapproval, "that his voice-recognition and speech-synthesis centres have been damaged. We'll have to teach him to speak all over again. Luckily, he learns several million times faster than a human being."
The scientist's fingers danced over the keyboard as he typed out a dozen words, apparently at random, carefully pronouncing each one as it appeared on the screen. Like a distorted echo, the words came back from the speaker grille - lifeless, indeed mechanical, with no sense of any intelligence behind them. This isn't the old Hal, thought Floyd. It's no better than the primitive speaking toys that were such a novelty when I was a kid.
Chandra pressed the REPEAT button, and the series of words sounded once again. Already, there was a noticeable improvement, though no one could have mistaken the speaker for a human being.
"The words I gave him contain the basic English phonemes; about ten iterations, and he'll be acceptable. But I don't have the equipment to do a really good job of therapy."
"Therapy?" asked Floyd. 'You mean that "he's - well, brain-damaged?"
"No," snapped Chandra. "The logic circuits are in perfect condition. Only the voice output may be defective, though it will improve steadily. So check everything against the visual display, to avoid misinterpretations. And when you do speak, enunciate carefully."
Floyd gave Captain Orlova a wry smile, and asked the obvious question.
"What about all the Russian accents around here?"
"I'm sure that won't be a problem with Captain Orlova and Dr Kovalev. But with the others - well, we'll have to run individual tests. Anyone who can't pass will have to use the keyboard."
"That's still looking a long way ahead. For the present, you're the only person who should attempt communication. Agreed, Captain?"
"Absolutely."
Only the briefest of nods revealed that Dr Chandra had heard them. His fingers continued to fly over the keyboard, and columns of words and symbols flashed across the display screen at such a rate that no human being could possibly assimilate them. Presumably Chandra had an eidetic memory, for he appeared to recognize whole pages of information at a glance.
Floyd and Orlova were just about to leave the scientist to his arcane devotions when he suddenly acknowledged their presence again, holding up his hand in warning or anticipation. With an almost hesitant movement, in marked contrast with his previous swift actions, he slid back a locking bar and pressed a single, isolated key.
Instantly, with no perceptible pause, a voice came from the console, no longer in a mechanical parody of human speech. There was intelligence - consciousness - self-awareness here, though as yet only on a rudimentary level.
"Good morning, Dr Chandra, This is Hal. I am ready for my first lesson."
There was a moment of shocked silence; then, acting on the same impulse, the two observers left the deck.
Heywood Floyd would never have believed it. Dr Chandra was crying.
IV: LAGRANGE
22
Big Brother
"... What delightful news about the baby dolphin! I can just imagine how excited Chris was when the proud parents brought it into the house. You should have heard the ohs and ahs of my shipmates when they saw the videos of them swimming together, and Chris riding on its back. They suggest we call it Sputnik, which means companion as well as satellite.
"Sorry it's been quite a while since my last message, but the newscasts will have given you an idea of the huge job we've had to do. Even Captain Tanya's given up all pretence of a regular schedule; each problem has to be fixed as it comes along, by whoever is on the spot. We sleep when we can't stay awake any longer.
"I think we can all be proud of what we've done. Both ships are operational and we've nearly finished our first round of tests on Hal. In a couple of days we'll know if we can trust him to fly Discovery when we leave here to make our final rendezvous with Big Brother.
"I don't know who first gave it that name - the Russians, understandably, aren't keen on it. And they've waxed quite sarcastic about our official designation TMA-2, pointing out to me - several times - that it's the best part of a billion kilometres from Tycho. Also that Bowman reported no magnetic anomaly, and that the only resemblance to TMA-1 is the shape. When I asked them what name they preferred, they came up with Zagadka, which means enigma. It's certainly an excellent name; but everyone smiles when I try to pronounce it, so I'll stick to Big Brother.
"Whatever you call the thing, it's only ten thousand kilometres away now, and the trip won't take more than a few hours. But that last lap has us all nervous, I don't mind telling you.
"We'd hoped that we might find some new information aboard Discovery. That's been our only disappointment, though we should have expected it. Hal, of course, was disconnected long before the encounter, and so has no memories of what happened; Bowman has taken all his secrets with him. There's nothing in the ship's log and automatic recording systems that we didn't already know.
"The only new item we discovered was purely personal - a message that Bowman had left for his mother. I wonder why he never sent it; obviously, he did ex
pect - or hope - to return to the ship after that last EVA. Of course, we've had it forwarded to Mrs Bowman - she's in a nursing home, somewhere in Florida, and her mental condition is poor, so it may not mean anything to her.
"Well, that's all the news this time. I can't tell you how much I miss you... and the blue skies and green seas of Earth. All the colours here are reds and oranges and yellows - often as beautiful as the most fantastic sunset, but after a while one grows sick for the cool, pure rays at the other end of the spectrum.
"My love to you both - I'll call again just as soon as I can."
23
Rendezvous
Nikolai Temovsky, Leonov's control and cybernetics expert, was the only man aboard who could talk to Dr Chandra on something like his own terms. Although Hal's principal creator and mentor was reluctant to admit anyone into his full confidence, sheer physical exhaustion had forced him to accept help. Russian and Indo-American had formed a temporary alliance, which functioned surprisingly well. Most of the credit for this went to the good-natured Nikolai, who was somehow able to sense when Chandra really needed him, and when he preferred to be alone. The fact that Nikolai's English was much the worst on the ship was totally unimportant, since most of the time both men spoke a computerese wholly unintelligible to anyone else.
After a week's slow and careful reintegration, all of Hal's routine, supervisory functions were operating reliably. He was like a man who could walk, carry out simple orders, do unskilled jobs, and engage in low-level conversation. In human terms, he had an Intelligence Quotient of perhaps 50; only the faintest outlines of his original personality had yet emerged.