I’M NOT SURE HOW MUCH time passed, maybe five minutes, maybe twenty. All I know is that the sky had begun to lighten and that it was Eddy who spoke first, saying, “Hydrogen. They feed on hydrogen. We’re safe.” I must have looked at him, because I remember clearly how pale he looked, how ill. “Jupiter 6?” I said, although I already knew the answer. “Why not?” He laughed a little to himself. “Cosmos. Carl Sagan. Hunters and floaters.” “Someone needs to toggle the propane,” said Karen, absently, it seemed, as though she were a million miles away. I looked at her to see a woman clearly in shock. “I’ll do it. Okay? You—just relax.” I looked at the apparatus for controlling the balloon. “The red lever?” She nodded and sniffed, like a helpless little girl, and I climbed to my feet. Eddy gra