فصل 34

CHAPTER THIRTY FOUR

The Orbiting Ice

Discovery was now deep inside the system of Saturn’s moons. The ship had passed inside the wide orbit of Phoebe. Ahead of it lay Japetus, Hyperion, Titan, Rhea, Dione, Tethys, Encaladus, Mimas - and the rings themselves. All the moons showed great detail through the telescope, and Bowman had sent back to Earth as many photographs as he could take.

But Japetus held most of his attention. One half of the satellite - which, like its companions, turned the same face always towards Saturn - was extremely dark and showed very little surface detail. In complete contrast, the other was largely covered by a brilliant white oval, about six hundred kilometers long and three hundred wide. It sat in the middle of Japetus, with its narrow ends pointing to the poles. It was so even and so sharp-edged that it looked as if it had been painted there. Because it looked so flat, Bowman wondered if it might be a lake of frozen liquid, but that would not explain its even appearance.

However, Bowman had little time to study it in detail; the most dangerous part of the voyage was rapidly approaching. As it flew past Jupiter, the ship had used the planet’s gravity to increase her speed. Now she must do the opposite. She had to slow down as much as possible so she did not escape from the Solar System and fly on to the stars. Her present path was designed to trap her, so she would become another moon of Saturn, going round on a three-million-kilometer-long oval orbit. At its near point she would come close to the planet; at its far point she would touch the orbit of Japetus.

The computers back on Earth, though their information was always three hours late, had told Bowman that everything was in order. The ship had to fly over the dark side of Saturn, out of radio contact with Earth and losing speed all the time, then rise up again into the sunlight and fly on for another three million kilometers. It would take her fourteen days to make that climb, crossing the paths of all the inside moons. Then she would meet Japetus.

If she failed, she would fall back towards Saturn and repeat her twenty-eight day orbit. But the next time round, Japetus would be far away, almost on the other side of the planet.

It was true that they would meet again, when the orbits of ship and moon came together for a second time. But that would be so many years ahead that, whatever happened, Bowman knew he would not see it.