A simple $3 toothbrush designed by the Indian-American astronaut Sunita Williams and her Japanese colleague has saved the $100-billion International Space Station, after they used it to replace a key power unit.

The decision to use the toothbrush to clean a bolt that gave Williams and Akihiko Hoshide so much trouble during an eight-hour spacewalk last week was made at a brainstorming session between the astronauts and NASA engineers on the ground.

They were trying to replace an electrical switching unit, but they couldn’t bolt it to the outside of the station, NBC News.Com reported. This was actually an extra spacewalk tacked to their mission after the stuck bolt prevented the astronauts from properly installing the power unit ‘MBSUs’ on the outpost’s backbone-like truss on August 30.

The International Space Station has four 100-kg MBSUs that harness power from the outpost’s solar arrays and distribute it throughout the orbiting complex.

The station was unable to relay power from two of the eight solar arrays on the massive orbiting complex without the use of one unit.

“Looks like you guys just fixed the station,” astronaut Jack Fischer radioed from the Mission Control at NASA’s Johnson Space Center in Houston.

At the beginning of the spacewalk, Williams and Hoshide removed the MBSU from where it was temporarily tied down with a tether last week. The spacewalkers undid the bolts, examined them for possible damage and inspected the corresponding receptacles on the MBSU for debris that was suspected to be inside.

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