Around the rim of the carrousel were five tiny cubicles, fitted out by each astronaut according to taste and containing his personal belongings. Only Bowman’s and Poole’s were now in use, while the future occupants of the other three cabins reposed in their electronic sarcophagi next door.
The spin of the carrousel could be stopped if necessary; when this happened, its angular momentum had to be stored in a flywheel, and switched back again when rotation was restarted. But normally it was left running at constant speed, for it was easy enough to enter the big, slowly turning drum by going hand-over-hand along a pole through the zero-gee region at its center. Transferring to the moving section was as easy and automatic, after a little experience, as stepping onto a moving escalator.
The spherical pressure hull formed the head of a flimsy, arrow-shaped structure more than a hundred yards long. Discovery, like all vehicles intended for deep space penetration, was too fragile and unstreamlined ever to enter an atmosphere, or to defy the full gravitational field of any planet. She had been assembled in orbit around the Earth, tested on a translunar maiden flight, and finally checked out in orbit above the Moon.
She was a creature of pure space – and she looked it. Immediately behind the pressure hull was grouped a cluster of four large liquid hydrogen tanks – and beyond them, forming a long, slender V, were the radiating fins that dissipated the waste heat of the nuclear reactor. Veined with a delicate tracery of pipes for the cooling fluid, they looked like the wings of some vast dragonfly, and from certain angles gave Discovery a fleeting resemblance to an old-time sailing ship,
At the very end of the V, three hundred feet from the crew-compartment, was the shielded inferno of the reactor, and the complex of focusing electrodes through which emerged the incandescent star-stuff of the plasma drive. This had done its work weeks ago, forcing Discovery out of her parking orbit round the Moon. Now the reactor was merely ticking over as it generated electrical power for the ship’s services, and the great radiating fins, that would glow cherry red when Discovery was accelerating under maximum thrust, were dark and cool.
Although it would require an excursion out into space to examine this region of the ship, there were instruments and remote TV cameras which gave a full report on conditions here. Bowman now felt that he knew intimately every square foot of radiator, panels, and every piece of plumbing associated with them.
By 1600, he would have finished his inspection, and would make a detailed verbal report to Mission Control, talking until the acknowledgment started to come in. Then he would switch off his own transmitter, listen to what Earth had to say, and send back his reply to any queries. At 1800 hours, Poole would awaken, and he would hand over command.
He would then have six off-duty hours, to use as he pleased. Sometimes he would continue his studies, or listen to music, or look at movies. Much of the time he would wander at will through the ship’s inexhaustible electronic library. He had become fascinated by the great explorations of the past – understandably enough, in the circumstances. Sometimes he would cruise with Pytheas out through the Pillars of Hercules, along the coast of a Europe barely emerging from the Stone Age, and venture almost to the chill mists of the Arctic. Or, two thousand years later, he would pursue the Manila galleons with Anson, sail with Cook along the unknown hazards of the Great Barrier Reef, achieve with Magellan the first circumnavigation of the world. And he began to read the Odyssey, which of all books spoke to him most vividly across the gulfs of time.
For relaxation he could always engage Hal in a large number of semi-mathematical games, including checkers, chess, and polyominoes. If Hal went all out, he could win anyone of them; but that would be bad for morale. So he had been programmed to win only fifty percent of the time, and his human partners pretended not to know this.
The last hours of Bowman’s day were devoted to general cleaning up and odd jobs, followed by dinner at 2000 – again with Poole. Then there would be an hour during which he would make or receive any personal call from Earth.
Like all his colleagues, Bowman was unmarried; it was not fair to send family men on a mission of such duration, though numerous ladies had promised to wait until the expedition returned, no one had really believed this. At first, both Poole and Bowman had been making rather intimate personal calls once a week, though the knowledge that many ears must be listening at the Earth end of the circuit tended to inhibit them. Yet already, though the voyage was scarcely started, the warmth and frequency of the conversations with their girls on Earth had begun to diminish. They had expected this; it was one of the penalties of an astronaut’s way of life, as it had once been of a mariner’s.
It was true – indeed, notorious – that seamen had compensations at other ports; unfortunately there were no tropical islands full of dusky maids beyond the orbit of Earth. The space medics, of course, had tackled this problem with their usual enthusiasm; the ship’s pharmacopoeia provided adequate, though hardly glamorous, substitutes.
Just before he signed off Bowman would make his final report, and check that Hal had transmitted all the instrumentation tapes for the day’s run. Then, if he felt like it, he would spend a couple of hours either reading or looking at a movie; and at midnight he would go to sleep – usually without any help from electronarcosis. Poole’s program was a mirror image of his own, and the two schedules dovetailed together without friction.
Both men were fully occupied, they were too intelligent and well-adjusted to quarrel, and the voyage had settled down to a comfortable, utterly uneventful routine, the passage of time marked only by the changing numbers on the digital clocks.
The greatest hope of Discovery’s little crew was that nothing would mar this peaceful monotony in the weeks and months that lay ahead.
18 – Through the Asteroids
Week after week, running like a streetcar along the tracks of her utterly predetermined orbit, Discovery swept past the orbit of Mars and on toward Jupiter. Unlike all the vessels traversing the skies or seas of Earth, she required not even the most minute touch on the controls. Her course was fixed by the laws of gravitation; there were no uncharted shoals, no dangerous reefs on which she would run aground. Nor was there the slightest danger of collision with another ship; for there was no vessel – at least of Man’s making – anywhere between her and the infinitely distant stars.
Yet the space which she was now entering was far from empty. Ahead lay a no-man’s land threaded by the paths of more than a million asteroids – less than ten thousand of which had ever had their orbits precisely determined by astronomers. Only four were over a hundred miles in diameter; the vast majority were merely giant boulders, trundling aimlessly through space.
There was nothing that could be done about them; though even the smallest could completely destroy the ship if it slammed into it at tens of thousands of miles an hour, the chance of this happening was negligible.
On the average, there was only one asteroid in a volume a million miles on a side; that Discovery should also happen to occupy this same point, and at the same time, was the very least of her crew’s worries.
On Day 86 they were due to make their closest approach to any known asteroid, It had no name – merely the number 7794 – and was a fifty-yard-diameter rock that had been detected by the Lunar Observatory in 1997 and immediately forgotten except by the patient computers of the Minor Planet Bureau.
When Bowman came on duty, Hal promptly reminded hint of the forthcoming encounter – not that he was likely to have forgotten the only scheduled in-flight event of the entire voyage, The track of the asteroid against the stars, and its coordinates at the moment of closest approach, had already been printed out on the display screens. Listed also were the observations to be made or attempted; they were going to be very busy when 7794 flashed past them only nine hundred miles away, at a relative speed of eighty thousand miles an hour.
When Bowman asked Hal for the telescopic display, a sparsely sprinkled star field flashed onto the screen. There was nothing that looked like an asteroid; all the images, even under the highest magnification, were dimensionless points of light.
“Give me the target reticule,” asked Bowman. Immediately four faint, narrow lines appeared, bracketing a tiny and undistinguished star. He stared at it for many minutes, wondering if Hal could possibly be mistaken; then he saw that the pinpoint of light was moving, with barely perceptible slowness, against the background of the stars. It might still be half a million miles away – but its movement proved that, as cosmic distances went, it was almost near enough to touch.