ISS crew continues testing to find a small leak aboard the station

The crew aboard the International Space Station is continuing to work to try and find the source of a small leak. Late Monday night, NASA reports that the Expedition 63 crew was awakened by flight controllers to continue troubleshooting a small leak aboard the space station that appeared to grow in size. Ground analysis of the modules tested overnight has isolated the leak location to the Zvezda Service Module's main work area.

Currently, additional work is underway to try to locate the source of the leak precisely. The leak has been under investigation for several weeks, and NASA is clear that it poses no immediate danger to the crew at the current leak rate. The leak has caused a slight deviation to the crew's schedule.

The leak's size has been identified overnight and is attributed to a temporary temperature change aboard the station; the overall rate of the leak is unchanged. The source of the leak has been pinpointed to the Russian module after leak checks were conducted previously in the American, European, and Japanese modules in the US segment of the station.

During the tests, the crew closed hatches between the Zvezda aft and forward sections and the passageways to the Pirs Docking Compartment and the Poisk module. It used an ultrasonic leak detector to collect data. After the checks, the crew opened the hatch between the segments and resumed regular activities.

The crew is also preparing to arrive at an uncrewed Cygnus cargo craft scheduled to launch Thursday night. Three new astronauts will also be heading to the station in the coming weeks. It's unclear at this time how exactly NASA plans to fix the leak permanently.