spacetoday.net: ISS power unit installed

Posted: Thu, Sep 6, 2012, 7:20 AM ET (1120 GMT)
ISS EVA 2012 September 5 (NASA)

Spacewalking astronauts successfully installed a power switching unit on the exterior of the International Space Station during a spacewalk Wednesday, less than a week after failing to do so during a previous EVA. Sunita Williams and Akihiko Hoshide spent six hours and 28 minutes outside the ISS on an EVA that ended at 1:34 pm EDT (1734 GMT). The two had attempted to install a new Main Bus Switching Unit (MBSU) last week but were stymied by a stuck bolt. On Wednesday's EVA the astronauts used tools, including a toothbrush, to clean metal shavings from the bolt hole before successfully installing a new bolt to latch the MBSU into place. The MBSU is used to route power from the station's solar arrays; without it installed, the station was able to use power from only six of its eight large arrays. The astronauts also installed a new camera on the station's Canadarm2 robotic arm, a task planned for last week's spacewalk but deferred because of problems with the MBSU installation.