Spacewalking astronauts lose piece of shielding that floats away CAPE CANAVERAL — Spacewalking astronauts lost an important piece of cloth shielding needed for the International Space Station on Thursday when it floated away. The entire 250-mile-high space station is protected, in some fashion, against possible debris strikes. The docking port was disconnected during a spacewalk last Friday by Kimbrough, the space station’s commander and a six-time spacewalker. The spacewalkers hooked up vital heater cables to the docking port and removed a cover from the top.