A malfunctioning cooling system part on the International Space Station may require an astronaut spacewalk to fix it if the team at
"Any time you have something like this, it's good news-bad news," said NASA astronaut Rick Mastracchio in a video-recorded interview on the agency's site. "Of course, the bad news is, the station's having problems and we have to go out and do a repair. The good news is, we have the spare parts, we have the training, we have the skills."
"And of course," he added, "going out and doing a spacewalk is very exciting -- yet very challenging."
Engineers continued to work on the problem for a third day after a pump in one of two ammonia cooling loops outside the station shut down Wednesday morning, officials said. The problem may come from a malfunctioning valve inside the pump that may not be modulating the temperature correctly.
Affected systems on the Japanese and European modules were moved over to the other cooling loop, officials said, and the space station can run just fine using only one cooling loop.
"Some of the science experiments have been shut down due to the lack of cooling.... We're still very comfortable up here," Mastracchio said.
But a resupply flight initially scheduled for later this month may need to be put off if they can't figure the problem out in time, Kenny Todd, the ISS mission operations integration manager, said in a NASA video interview.
"This is a position we don't want to be in long term," Todd said.
No plans have been announced for an astronaut spacewalk. The team at NASA Johnson is still experimenting with the faulty valve from ground control to see whether any clues, such as changes in temperature and flow rate, will allow them to determine what exactly has gone wrong.
"We're going to kick the can for a little bit," Todd said.
If a spacewalk is scheduled, it would come months after Italian astronaut Luca Parmitano nearly drowned in space after his malfunctioning spacesuit began to fill his helmet with water.
"You can imagine, you're in a fishbowl. ... That's not anything you take lightly," NASA flight director David Korth said at the time.