May 17, 2013
NASA Says Ammonia Leak All Plugged Up
Lee Rannals for redOrbit.com — Your Universe Online
According to the Associated Press, NASA confirmed on Thursday that the ammonia leak its astronauts fixed on the International Space Station last week is officially plugged up.
Astronauts aboard the space station had to quickly repair the leaky pump during an impromptu spacewalk over the weekend. The leak forced one of the station's seven power channels to go offline.
"Right now, we're feeling pretty good. We definitely got the big leak," Vareha said in a NASA broadcast from Mission Control in Houston.
He said engineers were not sure whether the pump replacement also took care of a smaller leak that had plagued the system for a few years, and it will take a little more time to know the full status of that.
“Mission Control ran the new pump while the spacewalkers watched for any ammonia snowflakes, but so far there have been no new signs of a leak. Long-term monitoring of the pump will be required to determine whether the pump replacement has fixed the leak,” the US space agency said after astronauts repaired the leak last week.
According to NASA, Expedition 35 Flight Engineers Chris Cassidy and Tom Marshburn successfully completed the spacewalk at 1:14 pm CDT. They set out at 7:44 am CDT, and slightly over two and one-half hours into the spacewalk, they removed the 260-pound pump controller from the P6 truss and replaced it with a spare one.
“Engineers believed the leak most likely was coming from in or around a 260-pound (118-kg) pump that pushes ammonia throughout the system. The coolant dissipates heat from electronics in space station´s solar-powered electrical system,” Reuters reporter Irene Klotz said on Saturday. “The station can be reconfigured to compensate for a system shutdown, but if a second problem should occur, that likely would mean a cutback in power available for the experiments.”
NASA said the P6 truss was the oldest component of the station's backbone, and was launched to the station on board space shuttle in November 2000.
“It was relocated from its original installation position to the far left side of the station during the STS-120 mission of the shuttle Discovery in October/November 2007," NASA said.