A voice called from below. Hunt rose to his feet, his movements slow and clumsy in his encumbering space suit, and clambered through the floor hatch and down a short ladder to the control cabin. The driver was stretching back in his seat, taking a long drink from a flask of hot coffee. Behind him, the sergeant in command of the vehicle was at a videoscreen, reporting back to base via comsat that they had reached their destination without mishap. The third crew member, a corporal who was to accompany Hunt and Alberts outside and who was already fitted out, was helping the professor secure his helmet. Hunt took his own helmet from the storage rack by the door and fixed it in place. When the three were ready, the sergeant supervised the final checkout of life-support and communications systems and cleared them to pass, one by one, through the airlock to the outside.

"Well, there you are, Vic. Really on the Moon now." Albert's voice came through the speaker inside Hunt's helmet. Hunt felt the spongy dust yield beneath his boots and tried a few experimental steps up and down.

"It's like Brighton Beach," he said.

"Okay, you guys?" asked the voice of the UNSA corporal.

"Okay."

"Sure."

"Let's go, then."

The three brightly colored figures—one orange, one red, and one green—began moving slowly along the well-worn groove that ran up the center of the mound of rubble. At the top they stopped to gaze down at the survey vehicle, already looking toylike in the gorge below.

They moved into the cleft, climbing between vertical walls of rocks that closed in on both sides as they approached the bend. Above the bend the cleft straightened, and in the distance Hunt could see a huge wall of jagged buttresses towering over the foothills above them—evidently the ridge described in Charlie's note. He could picture vividly the scene in this very place so long ago, when two other figures in space suits had toiled onward and upward, their eyes fixed on that same feature. Above it, the red and black portent of a tormented planet had glowered down on their final agony like . . .

Hunt stopped, puzzled. He looked up at the ridge again, then turned to stare at the bright disk of Earth, shining far behind his right shoulder. He turned to look one way, then back again the other.

"Anything wrong?" Alberts, who had continued on a few paces, had turned and was staring back at him.

"I'm not sure. Hang on there a second." Hunt moved up alongside the professor and pointed up and ahead toward the ridge. "You're more familiar with this place than I am. See that ridge up ahead there—At any time in the year, could the Earth ever appear in a position over the top of it?"

Alberts followed Hunt's pointing finger, glanced briefly back at the Earth, and shook his head decisively behind his facepiece.