14 DAY TRIAL // Officials at NASA reported on Wednesday, December 11, that they are assessing an issue with a faulty valve in a pump powering up the cooling system aboard the International Space Station (ISS). A similar situation occurred a couple of years ago, when the possibility of evacuating the station was proposed.
The orbital facility, which took 11 years and $100 billion (€72.5 billion) to complete, has two separate cooling loops, so that the system continues to operate even in case of emergency. However, it is not recommended for the entire facility to depend on a single cooling loop.
Due to its altitude of 402 kilometers (250 miles) above Earth's surface, servicing the ISS is not as simple as calling Triple A. This was made painfully obvious on August 1, 2010, when Loop A of its cooling system failed. Three spacewalks were required to fix the issue at the time, MSN reports.
According to Josh Byerly, a spokesman for the NASA Johnson Space Center (JSC), in Houston, Texas, the American space agency is investigating the autonomous shutdown of the pump valve. The component was turned off after sensors within the cooling loop detected abnormal temperature levels.
The NASA official also said that fixing this issue might require an unscheduled extravehicular activity (EVA), similar to the ones that occurred in 2010. “If it's a software problem, they could just do a software update or do a patch. If it's a hardware issue, that's something else,” he said.
“We'll know more in the next day or so,” Byerly told the media, adding that the six members of the Expedition 38 crew aboard the ISS are not in any immediate danger. “Some of the news reports that I've seen out there have been like ‘catastrophic shutdown.’ That's not at all what this is,” he said.
The International Space Station has not one, but three spare cooling pumps on shelves alongside its outer hull. As NASA prepared to retire its shuttles, it sent a wide variety of spare parts to the facility, in order to ensure that any possible contingency is covered.
If the situation degrades rapidly, and the ISS crew needs to be evacuated, this can be easily achieved through the two Russian-built Soyuz spacecraft that are always attached to the station. These vehicles can hold three astronauts each.
Since all ISS crewmembers arrive in groups of three on their dedicated spacecraft, evacuating the station is merely a matter of going inside the Soyuz and sealing the hatch between the capsule and the ISS. Astronauts aboard the station have rehearsed this emergency procedure innumerable times.