Who’s the ace among aces?

New tool helps identify astronauts with better spatial skills. On Oct. 30, 2007, astronauts aboard the Space Shuttle Discovery set out on a routine mission: installing two solar panels on the truss, or backbone, of the International Space Station. While the first panel deployed successfully, astronauts noticed a two-foot-wide tear in the second panel. To repair the tear, crewmembers devised a risky plan, sending an astronaut on a spacewalk while tethered to the shuttle's inspection arm. The mission marked the first time an astronaut had used the robotic arm in such a way - a potentially dangerous undertaking, as a wrong move could have electrocuted the spacewalker. In the end, the mission was a success, due partly to the robotic arm's operators, who were trained to maneuver the multijointed arm with high precision.