Emergency spacewalks planned to fix International Space Station

NASA is scrambling to solidify plans to fix the broken down cooling systems on the International Space Station during two spacewalks, currently planned for Friday and Monday. The systems broke down late Saturday July 31, triggering alarms that woke the six astronauts (three Russian and three American) currently onboard the station. NASA's flight controller said the astronauts are not in any danger, but that science experiments are on hold until the problem can be fixed.

The first spacewalk is set to begin Friday at 6:55 a.m. EDT, NASA officials said. The two planned spacewalks will be conducted by astronauts Douglas Wheelock and Tracy Caldwell Dyson. They will replace an ammonia pump module, which shut down Saturday. The pump's failure prompted the astronauts to shut down several other systems as well. The spare pump had been delivered to the station in July 2006, during STS-121.

Normally, major repair spacewalks take weeks of preparation. An unrelated spacewalk had already been planned for this Thursday, which would have been conducted by Wheelock and Dyson, so the space suits and equipment are ready to go. NASA decided late Monday evening that the spacewalk would be postponed to Friday to allow for more preparation.

In October 2010 the space station is expected to break the record for the longest continuously inhabited space station, a record currently held by Mir.