ARTICLE CONTINUES BELOW “You want to be like a rock climber,” Williams said. “You want to have a lot of upper extremity strength and endurance, but you don’t want to bulk up and not be able to fit in your spacesuit.” You also have to rethink everything you know. Say you’re trying to use a pistol grip tool — basically an electric drill — to loosen a bolt. You press the trigger. If you don’t stabilize yourself first, sometimes by locking yourself into a restraint system, the bolt won’t spin. You will. And you do everything wearing what amounts to bulky, cumbersome hockey mitts. The Polaris Dawn astronauts did not have the same, extensive task list as a spacewalk on the I.S.S. would. Instead, they spent only about 10 minutes each outside the capsule, performing a choreographed sequence of movements that tested the new suits. But during a spacewalk, you’re always on edge. A little mistake can mean a whole lot of trouble. “If you have a problem spacewalking, you may have the rest of your life to solve the problem,” Williams said. “It’s an environment that really does get your attention.” Things can always go wrong On Hadfield’s first spacewalk, he went temporarily blind. The anti-fog treatment on his visor got into both his eyes, but because he had trained multiple times in the pool on what to do if a crew member was incapacitated, he kept calm. “It was just a thing,” he said coolly. “I was more irritated that I wasn’t maybe going to be able to complete all of the objectives of the spacewalk, because you’re taking an enormous risk to go do one.” Likewise, the Polaris Dawn crew trained extensively, Hadfield said. They had backup plans to backup plans, and the spacewalk happened largely without a hitch. While Isaacman had to manually open the capsule hatch, something that should have happened with the press of a button, and Gillis spotted bulges in the hatch seal, neither hitch presented a problem for the mission. The astronauts will be exhausted Even with only a few minutes outside the capsule, the Polaris Dawn crew is guaranteed to be exhausted afterwards. “It’s a marathon of focus, in a way. You just make sure you don’t make a mistake,” MacLean said. “I was spent. I slept right through the night.”