But now, with that building far behind, the time between clicks was down to five seconds. I must be getting close, Glen thought as he drove. With one hand on the wheel, he grabbed Salerno’s notebook and checked the map. It looks like I’m headed for the northeast area of the moon. He continued driving, listening for the clicks to guide his path. They were now coming every four seconds . . . three . . . two . . . one . . . until at last, Glen couldn’t tell when one ended and another began. The trouble was, he didn’t see anything. There was no obelisk, no building, no Salerno. Instead, there was just the barren, rocky grayness of the moon. Hearing the space between clicks return to one second, Glen circled back but still saw nothing. “It should be right here,” he said as he allowed the rover to slowly drift forward. “Why don’t I—?” Just then, Glen felt one of his front tires hit something. He backed up and got out to see what it was. It didn’t look like much, just a small triangular rock.
