Air leak continues despite repairs on Zvezda module of ISS
According to a report today in the Russian press, the air in the Zvezda module of ISS continued to leak away slowly during a test, following this week’s repair of two cracks in the module’s hull.
At about 07:00 GMT on Saturday, ISS cosmonaut Sergei Ryzhikov told a specialist at the Mission Control Center, located near Moscow, that the pressure in the intermediate chamber of the Zvezda module was 678 millimetres of mercury. The pressure stood at 730 millimetres of mercury on Friday evening, right after the hatch of the compartment was closed. Thus, the pressure in the chamber decreased by 52 millimetres of mercury over 11.5 hours.
Based on the thorough nature of the two repairs, this leak must be coming from another very tiny leak that has not yet been detected. Though the leak is very slow and thus not an immediate threat to the astronauts on board, it suggests once again that the leaks are coming from stress fractures resulting from Zvezda’s 20-plus years in orbit. If so, the problem is very serious indeed. Zvezda is the central module for ISS. Replacing it will not be simple or easy.
According to a report today in the Russian press, the air in the Zvezda module of ISS continued to leak away slowly during a test, following this week’s repair of two cracks in the module’s hull.
At about 07:00 GMT on Saturday, ISS cosmonaut Sergei Ryzhikov told a specialist at the Mission Control Center, located near Moscow, that the pressure in the intermediate chamber of the Zvezda module was 678 millimetres of mercury. The pressure stood at 730 millimetres of mercury on Friday evening, right after the hatch of the compartment was closed. Thus, the pressure in the chamber decreased by 52 millimetres of mercury over 11.5 hours.
Based on the thorough nature of the two repairs, this leak must be coming from another very tiny leak that has not yet been detected. Though the leak is very slow and thus not an immediate threat to the astronauts on board, it suggests once again that the leaks are coming from stress fractures resulting from Zvezda’s 20-plus years in orbit. If so, the problem is very serious indeed. Zvezda is the central module for ISS. Replacing it will not be simple or easy.