Rendezvous With Rama - Arthur C. Clarke Page 0,4

metal plain. The northern face of Rama was a gigantic sundial, measuring the swift passage of its four-minute day.

Landing a five-thousand-ton spaceship at the center of a spinning disc was the least of Norton’s worries. It was no different from docking at the axis of a large space station; Endeavour’s lateral jets had already given her a matching spin, and he could trust Lieutenant Joe Calvert to put her down as gently as a snowflake, with or without the aid of the navigation computer.

“In three minutes,” said Calvert, without taking his eyes from the display screen, “we’ll know if it’s made of antimatter.”

Norton grinned, recalling some of the more hair-raising theories about Rama’s origin. If that unlikely speculation was true, in a few seconds there would be the biggest bang since the solar system had been formed. The total annihilation of ten thousand tons would, briefly, provide the planets with a second sun.

Yet the mission profile had allowed for even this remote contingency. Endeavour had squirted Rama with one of her jets from a safe thousand kilometers away. Nothing whatsoever had happened when the expanding cloud of vapor arrived on target, and a matter-antimatter reaction involving even a few milligrams would have produced an awesome fireworks display.

Norton, like all space commanders, was a cautious man. He had looked long and hard at the northern face of Rama in choosing the point of touch-down. After much thought, he had decided to avoid the obvious spot—the exact center, on the axis itself. A clearly marked circular disc, a hundred meters in diameter, was centered on the pole, and he had a strong suspicion that this must be the outer seal of an enormous air lock. The creatures who had built this hollow world must have had some way of taking their ships inside. This was the logical place for the main entrance, and he thought it might be unwise to block the front door with his own vessel.

But this decision generated other problems. If Endeavour touched down even a few meters from the axis, Rama’s rapid spin would start her sliding away from the pole. At first, the centrifugal force would be very weak, but it would be continuous and inexorable. Norton did not relish the thought of his ship slithering across the polar plain, gaining speed minute by minute until she was slung off into space at a thousand kilometers an hour when she reached the edge of the disc.

It was possible that Rama’s minute gravitational field—about one-thousandth of Earth’s—might prevent this from happening. It might hold Endeavour against the plain with a force of several tons, and if the surface was sufficiently rough, the ship might stay near the pole. But Norton had no intention of balancing an unknown frictional force against a quite certain centrifugal one.

Fortunately, Rama’s designers had provided an answer. Equally spaced around the polar axis were three low pillbox-shaped structures, about ten meters in diameter. If Endeavour touched down between any two of these, the centrifugal drift would fetch her up against them, and she would be held firmly in place, like a ship glued against a quayside by the incoming waves.

“Contact in fifteen seconds,” said Calvert.

As he tensed himself above the duplicate controls, which he hoped he would not have to touch, Norton became acutely aware of all that had come to focus on this instant of time. This, surely, would be the most momentous landing since the first touch-down on the Moon, over a century and a half ago.

The gray pillboxes drifted slowly upward outside the control port. There was the last hiss of a reaction jet, and a barely perceptible jar.

In the weeks that had just passed, Commander Norton had often wondered what he would say at this moment. But now that it was upon him, history chose his words, and he spoke almost automatically, barely aware of the echo from the past:

“Rama Base. Endeavour has landed.”

As recently as a month ago, he would never have believed it possible. The ship had been on a routine mission, checking and emplacing asteroid warning beacons, when the order came. Endeavour was the only spacecraft in the solar system that could possibly make a rendezvous with the intruder before it whipped around the Sun and hurled itself back toward the stars. Even so, it had been necessary to rob three other ships of the Solar Survey, which were now drifting helplessly until tankers could refuel them. Norton was afraid that it would be a long time