2001_ A Space Odyssey - Arthur C. Clarke [40]
It was racing past them at almost thirty miles a second; they had only a few frantic minutes in which to observe it closely. The automatic cameras took dozens of photographs, the navigation radar’s returning echoes were carefully recorded for future analysis — and there was just time for a single impact probe.
The probe carried no instruments; none could survive a collision at such cosmic speeds. It was merely a small slug of metal, shot out from Discovery on a course which should intersect that of the asteroid.
As the seconds before impact ticked away, Poole and Bowman waited with mounting tension. The experiment, simple though it was in principle, taxed the accuracy of their equipment to the limits. They were aiming at a hundred-foot-diameter target, from a distance of thousands of miles…
Against the darkened portion of the asteroid there was a sudden, dazzling explosion of light. The tiny slug had impacted at meteoric speed; in a fraction of a second all its energy had been transformed into heat. A puff of incandescent gas had erupted briefly into space; aboard Discovery, the cameras were recording the rapidly fading spectral lines. Back on Earth, experts would analyze them, looking for the telltale signatures of glowing atoms. And so, for the first time, the composition of an asteroid’s crust would be determined.
Within an hour, 7794 was a dwindling star, showing no trace of a disk. When Bowman next came on watch it had vanished completely.
They were alone again; they would remain alone, until the outermost of Jupiter’s moons came swimming up toward them, three months from now.
Chapter 19
Transit of Jupiter
Even from twenty million miles away, Jupiter was already the most conspicuous object in the sky ahead. The planet was now a pale, salmon-hued disk, about half the size of the Moon as seen from Earth, with the dark, parallel bands of its cloud belts clearly visible. Shuttling back and forth in the equatorial plane were the brilliant stars of Io, Europa, Ganymede, and Callisto — worlds that elsewhere would have counted as planets in their own right, but which here were merely satellites of a giant master.
Through the telescope, Jupiter was a glorious sight — a mottled, multicolored globe that seemed to fill the sky. It was impossible to grasp its real size; Bowman kept reminding himself that it was eleven times the diameter of Earth, but for a long time this was a statistic with no real meaning.
Then, while he was briefing himself from the tapes in Hal’s memory units, he found something that suddenly brought the appalling scale of the planet into focus. It was an illustration that showed the Earth’s entire surface peeled off and then pegged, like the skin of an animal, on the disk of Jupiter. Against this background, all the continents and oceans of Earth appeared no larger than India on the terrestrial globe.
When Bowman used the highest magnification of Discovery’s telescopes, he appeared to be hanging above a slightly flattened globe, looking down upon a vista of racing clouds that had been smeared into bands by the giant world’s swift rotation. Sometimes those bands congealed into wisps and knots and continent-size masses of colored vapor; sometimes they were linked by transient bridges thousands of miles in length. Hidden beneath those clouds was enough material to outweigh all the other planets in the Solar System. And what else, Bowman wondered, was also hidden there?
Over this shifting, turbulent roof of clouds, forever hiding the real surface of the planet, circular patterns of darkness sometimes glided. One of the inner moons was transiting the distant sun, its shadow marching beneath it over the restless Jovian cloudscape.
There were other, and far smaller, moons even out here — twenty million miles