He could not leave the ship, if there was no deputy commander to take over from him. Athena knew the present state of affairs; it was no use trying to fool her. She would not let him go-and, without her cooperation, he could not even open the airlocks.
It was a maddening situation, and illustrated perfectly the lack of initiative shown by even the most advanced computers. He had spent almost an hour with Athena analyzing this mission, and not once had she reminded him that he could not carry it out....
The captain of the Discovery was a stubborn man, particularly when he was frustrated. He looked at his chronometer; there was still plenty of time. Then, angry at Athena and at himself, yet coolly determined on his plan of action, he climbed out of the capsule, shucked off his spacesuit, and returned to the Control Deck.
The laws governing Athena's behavior were not inviolable; like any computer, she could be reprogrammed. But this was a skilled job, and it took time. When Bowman had consulted the logic diagrams, decided which steps could be cut out, checked that he had not introduced undesired side-reactions, run the new program through several times, and corrected a number of trivial mistakes, he had wasted more than an hour. Yet this was one operation that certainly could not be hurried; if the revised program was faulty, Athena might let him out of the ship-but she might not allow him to return.
Before he left the Control Center, he checked the position of the drifting antenna once more, both visually and by radar. It was now considerably further away, and when he recomputed the mission he was alarmed to find that he would have only about an hour of working time when he caught up with the runaway hardware. But that should be sufficient, all he had to do was to make contact with the antenna and push it gently back toward the ship. It seemed a straightforward enough operation, and he did not anticipate any difficulty.
There were no protests from Athena, and no further delays in the airlock. At his command, the door swung open into space.
Like a tiny, complex toy, surrounded by stars and the distant glow of the Milky Way, Discovery hung in space between Mars and Jupiter. She seemed absolutely motionless, not even rotating, but in reality she was still leaving the Sun at almost a million miles a day. The tiny, shrunken Sun, whose pale rays had long lost the power of bringing warmth.
One might have watched the ship for hours, even for days, and seen no sign of life. Yet now a black circle had appeared in the hull, as a door swung out into nothingness. From that circle slowly emerged the glittering, ungainly shape of a space capsule. Bowman and Poole were leaving Discovery.
With great difficulty Bowman had sealed Poole into his suit, for he did not wish to see the transformation which the body of an unprotected man undergoes in a vacuum. It was an extremely expensive coffin, this armor that had been built to guard him in life. But it was of no use to anyone else; it had been tailored to fit Poole, and now would perform this last service for him.
He set the timer for a five-second burst, and punched the firing key. With a faint hiss, the jet burst into life; he felt the momentary surge of weight as the pod's seat pressed against him with its fifth-of-a-gee acceleration. Then it was over-but he was moving away from Discovery at twenty miles an hour.
For one horrible instant, it seemed that the metal hands of the space pod had become entangled in the harness of the suit, but he managed to get them loose. Then the body was floating beside him, no longer in contact, but still sharing his speed as they both drifted away from the ship.
And now Kelvin Poole was following the road along which Peter Whitehead had already traveled. Both of them, in strange and literal truth, were on their way to the stars. For they were moving fast enough to escape from the Solar System; though they would sweep past Jupiter, even its giant gravity could never capture them. They would sail onward through the silence, passing the orbits of the outer planets one by one; and only then would their journey really begin-a journey that would never end, and might outlast Earth itself.
It was well that David Bowman had other work to do; he had no time for sorrow or regret. With great care, he aimed the pod toward its goal, now more than five hundred miles away, and signaled for the calculated twenty-five seconds of firing time.
He was only a quarter of a mile away, but moving at over a hundred miles an hour, when the period of powered flight ended. Discovery already looked too small and remote for comfort, she would soon grow smaller still. About a thousand feet from the ship, a just-identifiable package was hanging in space, apparently motionless. But Bowman knew that it was traveling steadily outward, and that when he returned Kelvin Poole would no longer be in sight. Now there was nothing he could do, except sit and wait for five hours while Alice coasted to her destination.
After a few minutes, he had to look hard to find Discovery; she was a rather dull star, easily lost against her more brilliant companions. Before the voyage was half completed, he could no longer see her with the unaided eye, and he was glad that he had programmed Athena to send him a regular situation report, running through the main instrument readings over and over again. That calm voice quoting temperatures and pressures and radiation levels was an assurance of normalcy and stability in me little world from which he had temporarily exiled himself. He might have chosen music, but had decided against it: it would have reminded him too closely of Whitehead's last moments.
When Discovery was no longer visible, he tried to concentrate on his destination; though the drifting antenna was easy enough to locate by the capsule's radar, and he knew the exact moment when he would intercept it, he nevertheless felt a surge of relief when he saw one star becoming brighter in the sky ahead. Soon he could make out the details of the structure-and then, quite suddenly, it was time to decelerate, with another twenty-five-second burst of power.
He brought the pod almost to rest while it was still a hundred yards from the antenna, for he dared not risk damaging it by his jet blast. As he drifted slowly toward it, he studied its condition, and planned his line of attack.
The six delicate, curving rods of metal that formed the main elements of the parabolic dish were shaped like the ribs of an umbrella, and were almost as fragile. They were covered by a fine, metallic net, that looked quite beautiful as it sparkled in the sun like a giant spider's web. Around the rim of the parabola smaller antennas sprouted; some of them had snapped off and hung dangling in space. One of the main ribs had also been broken, but on the whole there was surprisingly little damage.
At the center of the big dish was the universal joint mechanism which could aim it with fractional- degree accuracy to any quarter of the sky; about ten feet of supporting mast, snapped cleanly, and trailing wires and cables, was attached to this. The initial impact had started the system pinwheeling, at the rate of about two revolutions a minute, and Bowman realized that he would have to kill this spin before he could attempt any towing.
At close quarters, this whirling umbrella was uncomfortably impressive, and he was not sure how to tackle it. Bowman had done very little work in space itself, and was not skilled in extravehicular operations-for no man could become an expert in all astronautical techniques. In theory, he could carry out any maneuver with his control jets, and even perform such remarkable feats as tying knots with the mechanical fingers of the remote manipulator, or "waldoes." But that was theory, he lacked the practice, and as he slowly drifted up toward the rotating mass of wires and spars he began to realize that he might have bitten off more than he could chew. To make matters worse, he was now desperately tired.
He brought Alice completely to rest about fifty feet from the antenna, braking the pod with a gentle puff from the retros, and considered his next move. If he tried to grab this slowly turning buzz saw, it would donate some of its momentum to him, and he would start to spin with it. True, he could de-spin it with his side jets-but this was exactly the sort of situation in which even a skilled space construction worker could become hopelessly disoriented.
First he thought of lassoing the thing with his safety line, b
ut then he realized that this would only make matters worse-the antenna would simply wind him in until he collided with it. The impact would be negligible, but he might be in grave danger if the pod became entangled in this spinning mass, and he could not extricate himself again.
Time was steadily running out, but he dared not hurry. He had to think calmly and clearly, tired though he was. In principle, the answer to his problem in dynamics was quite straightforward; it was rather like docking at a spinning space station. If he approached along the axis of rotation, and matched the antenna's spin before he made contact with it, the impact would be as gentle and as harmless as a kiss. He could then clutch the main spars of the antenna with his waldoes, and now that it was firmly attached to the pod, could start to kill the spin. When that had been done he could begin his cosmic bulldozer act, cancel the outward velocity of all this priceless wreckage, and head it back toward home.
But this was not a neatly symmetrical structure like a space station, with a clearly defined axis about which it was turning. It was a huge, shallow dish, badly warped at one side, with some heavy equipment dangling from its center-the whole thing tumbling over and over in space. He maneuvered slowly around it, keeping his distance and trying to locate the spin axis.
Before long, he was hopelessly confused. His mind became full of a slowly rotating montage of curved rods and wires and glittering metallic mesh, through which the stars appeared and disappeared, until he could not be sure what was turning and what was stationary. If he ignored the background of the universe and concentrated on the antenna, there would be no problem, but the universe was not easy to ignore.
Even if he had been in good condition, not exhausted and depressed, he might have succumbed sooner or later. No one is wholly immune to space sickness, however experienced he may be, if the circumstances are right. And in this case, the circumstances were perfect.
The attack hit suddenly, without warning. The stars and the antenna blurred, and Bowman had an overwhelming conviction that he was spinning rapidly in space. He gritted his teeth together as that cold, clammy sensation- never forgotten once it had been experienced-swept over his body. With all the strength of will he could muster, he tried to regain control of his rebellious entrails.
The first urgent task was to close his eyes, and shut out the vision of that spinning chaos-shut it out mentally as well as physically. This was a great help; after a few minutes he felt that he had averted an immediate catastrophe. Presently he dared to look at his instrument panel- that, after all, was one fixed thing in his universe, and he tried to concentrate his attention upon it.
Slowly the dials and numbers came back into focus, and presently he began to feel a little better. The queasy sensation in the pit of his stomach ebbed away, but he dared not risk a relapse by looking out of the window. He was still coming back to normal when Athena suddenly reminded him of the inexorable passage of time.
"fifteen minutes to return sequence," she called, from the now far-distant and steadily receding ship.
Only fifteen minutes! It was incredible. Bowman glanced at his watch to confirm the fact, but he did not really doubt that Athena was telling the truth.
He must make the effort now, or not at all. It was inconceivable to have come all this way, and to be frustrated by a brief spasm of bodily weakness. Slowly, he raised his eyes from the instrument board and stared out the window.
Let's see, he told himself firmly. That point just in front of the servo-motor seems to be almost stationary. If I move in and grab it there . . .
He fed a gentle burst to the rear jet, and Alice drifted toward the turning saucer. At the same time, he flexed the pod's mechanical arms, opening and closing the claws so that they would be ready to grip as soon as the opportunity arose.
He made contact; the claws snapped shut. After that, things began to happen rather quickly.
There was a twisting sensation, as the antenna tried to impart its spin to the pod. Then, almost like some willful living creature-a bucking bronco that did not wish to be ridden-it started to flip over, changing its direction of rotation completely.
Bowman knew at once what had happened, but that did not help him in the least. The diabolical thing was like a gyroscope that had started to precess, because torque had been applied to it. It was tumbling in space, and he was tumbling with it.
In a few seconds it would take up a new, stable mode of rotation, turning more slowly now because of his parasitic mass. But in those few seconds, he would be completely incapacitated.
He released the claws; the antenna gave him a final, gentle swipe and Alice broke away, turning over and over with the spin she had acquired in the transaction. Bowman just managed to find the EMERGENCY DESPIN button; then he had to fight his own private battle again.
He felt and heard the brief stabbing of the jets as the pod's gyros and autopilot, unaffected by visceral confusion, straightened things out. After that there was a long silence, broken only by Athena's emotionless voice saying: "Ten minutes to return sequence. Repeat, ten minutes to return sequence." But still he did not open his eyes.
Not until Athena had called: "Five minutes to return sequence. Repeat, five minutes to return sequence" did he risk a look at the external world again. The stars were reassuringly motionless; he glanced very quickly at the antenna-so quickly that he had no time to grasp its current antics. He merely noted, with satisfaction, that it was a good hundred feet away.
He knew when he was beaten, and was too tired even to feel much sense of disappointment. Slowly he turned Alice toward the now invisible star of the ship, and checked and rechecked the direction in which she was aimed, and fed just less than half his remaining fuel to the motor. Then, as soon as he was well on his homeward journey, he ordered Athena: "Wake me up in three hours," and made her repeat back her instructions.
That was all he knew until he saw the ship again, still a hundred miles away. It began to grow minute by minute, from a star to a tiny world; and presently he could see the open airlock.
One loneliness was almost over; another was about to begin.
[In this version, Bowman managed to revive the three remaining sleepers, Kaminski, Hunter and Kimball. Discovery made rendezvous with Jupiter, and went into orbit round the giant planet.]
JOVEDAY
The parking orbit in which the ship now moved was a million-mile-long ellipse, coming to within only fifty thousand miles of Jupiter and then swinging out to the orbit of Callisto. Discovery could retrace it forever, if she pleased, making one complete circuit every seven days until the end of time. Sooner or later she would pass within a few thousand miles of each of the inner moons, and could survey them all in detail. And though she would be unable to land on any of them, she still carried enough fuel to make any orbit changes that would improve opportunities for observation.
That seven-day period was very convenient. The first turn around Jupiter had been on a Sunday morning, by the Earth calendar; they would skim past Jupiter, therefore, every Sunday for the whole of the mission. By Wednesday evening they would be out at their far point, the orbit of Callisto, and then the fall back to Jupiter would begin again. It was not surprising that Sunday was soon informally christened "Joveday."
On the very first Monday, on the outward leg of their first orbit, Discovery passed within thirty thousand miles of the satellite Europa. There would be closer approaches later, but this was a good opportunity for the crew to practice with their battery of instruments. They had to learn to make the most of the precious moments when the worlds they had come so far to study grew from points to disks and then to swiftly passing globes.
A group of telescopic cameras mounted in a kind of gun turret outside the Control Deck produced images which could be inspected on monitors inside the ship; then they were stored in a solid-state memory unit which could hold several million high-quality pictures. After a fly-by had been completed, these could be played back and examined at leisure under the different degrees of magnification.<
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There were also several spectrometers, operating from the short ultraviolet out into the far infrared. These should give dues to the chemical composition of the worlds that were being examined, but their records could be fully interpreted only by the experts back on Earth.
The infrared scanner, on the other hand, provided information of immediate value, which could be understood at a glance. It reproduced a "heat map" of the body at which it was pointed, and so would reveal at once any sources of thermal energy. Originally developed for military purposes, it could spot a power plant even if it was buried under a thousand feet of ice. Since any conceivable civilization or technology-or indeed any living creature- must produce heat, the infrared scanner was one of the most promising instruments at Discovery's command.
The most spectacular, and controversial, instrument that the ship carried was a laser spectrograph, which had been developed especially for the mission, despite the protests of a large section of the scientific community. One critic had said sarcastically, "Why not drop an atom bomb and photograph the debris?"
The idea behind the instrument was very simple. An extremely powerful laser beam was focused through a system of mirrors, on to a target which might be an asteroid or satellite a few hundred miles away. In a fraction of a second, the object receiving the laser pulse was heated to incandescence, producing its characteristic spectrum. The optical system that sent out the beam caught the returning flash of light, which was then photographed and analyzed. And so it was possible to find the composition of a cold, dark, and inaccessible body that might be racing past at thousands of miles an hour.