The car, its blue-white beams providing a narrow wedge of light on the surface ahead, trundled along at a sedate five kilometers an hour. The ship had landed close to the planetary equator, and the calm heavens wheeled steadily overhead. The pattern would repeat every twenty-nine hours, with no promise ever of returning day. Although the air felt perfectly still, at some time after the cold began there had been strong winds. The carbon dioxide snow had here and there blown into banks and deep drifts. Hans avoided them and kept his eyes fixed on the edge of the zone of visibility provided by the car’s lights. He could detect objects only to a distance of perhaps two hundred meters. After the three-kilometer mark he found himself impatiently trying to see beyond the narrow illuminated cone. He was filled with a combination of excitement and uneasiness. It was one thing to believe that you were right, and quite another to have proof to show to others.
At last, he saw far ahead a change in the landscape. The frozen drifts rose higher and beyond them stood a regular, sawtoothed barrier. He had been waiting for this, but the others must have been keeping their own close watch. Before Hans was sure of what he saw, Lara Quistner said “What is that?” At the same moment Darya Lang put a hand on Rebka’s arm. “Hans, we should stop until we know what’s ahead.”
“I know what it is.” Rebka kept the vehicle moving forward at the same slow pace. “I saw hundreds of these on the high-resolution orbital images. They were all partly covered by blown snow, but they are too regular in shape to be natural.”
“Regular how?”
“Nature often makes circles, but it seldom makes right angles. What we are seeing is a wall. I’d say it’s close to ten meters high, and it forms almost a perfect square.”
“A walled town?” Ben Blesh had been perched on an uncomfortable rear seat. He pressed forward between Hans Rebka and Darya Lang, too interested to be either critical or argumentative. “Back in the Orion arm a fortification like this would mean at least a Level Two civilization.”
Darya added, “But no higher than a Level Three. Walled cities go away as soon as the means to destroy them are developed. So these people didn’t have explosives and artillery.”
“Also, they didn’t expect attacks from the air.” Rebka halted the vehicle thirty meters short of the wall. “We’re talking pre-industrial here. No aircraft, so no spacecraft. An intelligent species—we’ll want to confirm that by looking inside the wall—but without the technology needed to escape. These people were in the worst possible situation. They knew what was happening to them, and they had plenty of time to worry about it. But without spaceflight, and pretty advanced spaceflight at that, there was no chance at all of their survival.”
The others were silent for a while. At last Ben Blesh said, “Captain Rebka, how long do you think it took?”
“I’ve been trying to answer that question. So far I’ve been unsuccessful. The
Lara Quistner said softly, “Left to die slowly, in the cold and dark. It’s an awful tragedy. If only some spacefaring species in the Sag Arm had known about it, these people could have been helped.”
“Some spacefaring species did know. Stars can explode and stars can kill you off with a solar flare big enough to wipe out all planetary life. We’ve all heard of cases where that happened. But stars do not simply
Hans Rebka had been studying the wall on their left as the car drove along parallel to it. He stopped where the drifted snow was less deep and formed a shallow V-shaped cut like a valley leading right up to the wall.
“A fortified town must have a way for people and goods to get in and out. It’s time to use our digging equipment. I suspect that we have reached one of the entry gates.”
He was starting to climb down, but Darya again put a hand on his suited arm. “Hans, do we really need to go through with this?”