By David Shiga
After the International Space Station started losing air pressure in January 2004, astronauts hunted for 2 weeks before finding the leak near a porthole. Though it worried mission controllers, the leak never endangered the people on board.
Since then, NASA’s been searching for a fast way to find such leaks. Now, NASA-funded researchers have discovered that listening for high-frequency sound waves rippling through a spacecraft’s hull can do that job.
The metal skin of the International Space Station is constantly threatened by micrometeorites and by debris from previously launched satellites and spacecraft. Zipping toward the station as fast as 15 kilometers per second, even a millimeter-size fragment can punch a hole through the hull.