The result was not encouraging. In the three hours remaining, there was simply no way that Ymir ’s attitude control thrusters—designed for tiny adjustments over long spans of time—could neutralize her tumble. The tumble wasn’t especially fast—the crew in the command module could barely sense that they were rotating—but it was enough to make the next rocket burn impossible. And if they couldn’t make that burn in three hours, they’d scrape the atmosphere again in an additional four, and again eight hours after that. They might survive one more ride like the first one, but they couldn’t survive two.