Dave Scott was not about to pass by an interesting rock without stopping. It was July 31, 1971, and he and Jim Irwin, his fellow Apollo 15 astronaut, were the first to drive on the moon. After a six-hour inaugural jaunt in the new lunar rover, the two were heading back to their lander, the Falcon, when Scott made an unscheduled pit stop.
West of a crater called Rhysling, Scott scrambled out of the rover and quickly picked up a black lava rock, full of holes formed by escaping gas. Scott and Irwin had been trained in geology and knew