He had been focusing all of his attention in the other direction, on Peach Pit and its iron-rich "children." These were still visible, through increasingly thick clouds of rocky debris. When the White Sky happened they would vanish into a cloud of dirt, and he might not see them for a while. So he had been looking at PP1, PP2, and PP3 while the looking was still good, nailing down their exact orbital parameters, taking high-res photographs. PP3 was especially interesting. It was a congealed glob of mostly iron, similar in composition to Amalthea. It was some fifty kilometers in diameter. And it had a deep cleft on one side, comparable in size to the Grand Canyon, apparently formed by a collision that had rent its outer skin while it was partly congealed. Doob had begun calling PP3 Cleft.