An Iowan played a key role in this morning’s high-flying space repair job. Astronaut Jim Kelly of Burlington used the shuttle Discovery’s robotic arm to help two fellow astronauts install a new steering gyroscope on the International Space Station. It’s the mission’s second of three scheduled spacewalks, but NASA is considering whether to add a fourth spacewalk to do repairs on Discovery’s heat shield. Several strips of ceramic cloth are sticking out between the thick thermal tiles on the belly of the shuttle. NASA engineers are still mulling whether those strips pose a risk to Discovery upon fiery re-entry into the atmosphere.