A bit beyond Earth’s atmosphere, NASA’s International Space Station (ISS) orbits high above the continents. Those who may have glimpsed it reflecting light on Saturday night might have also known that floating nearby out in space, two NASA astronauts were working frantically to conduct dangerous repairs to the station.
Ten days ago, one of two cooling loops which kept external and internal equipment aboard the station from overheating failed and forced a shutdown of all nonessential systems, leaving the station vulnerable and reliant upon a single cooling system. Nearly all scientific research in progress on the station has been stopped in an effort to limit strain the remaining cooling loop.
An earlier attempt was made to repair the loop via remote command, but failed. A second attempt at repairing the loop called for astronauts to use another valve to monitor the temperature of the loop, which worked to a small degree but was not considered a good enough solution. NASA then decided to go ahead with spacewalks to solve the problem by entirely replacing the pump by hand.
Saturday, American astronauts Michael Hopkins and Rick Mastracchio were sent out to remove the ammonia pump and prep the area for a replacement pump with a working valve. Mastracchio appeared to have little problem working on his end of the assignment, unhooking the electrical lines as well as the ammonia fluid line from the pump. However, midway into the operation, he reported having to up the heat in his boots because his feet were freezing. Mission Control hesitated in continuing the spacewalk, but went on until about two hours later, when Mastracchio pulled the pump, which is about the size of a double refrigerator door, away from the space station and requested that they call it a day.
When Mastracchio returned to the station, it was found that his suit was accumulating water, which led to the chill in his toes. NASA is still trying to figure out why the suit malfunctioned. The astronauts’ suits are nearly as old as the space shuttles, so NASA can expect some breakdown, making these repairs all the more dangerous to conduct. The spacewalk went on for five hours and 28 minutes in total, about an hour shorter than previously planned.
Spacewalks had been suspended in July when another space suit issue arose, nearly killing the astronaut wearing it. Italian Luca Parmitano nearly drowned when water from the suit’s cooling system flooded into his helmet. Hopkins wore that same space suit on this exercise out, though it and Mastracchio’s were fitted with several additional safety features, such as absorbent pads and snorkels.
The next spacewalk has been postponed until a spare space suit can be reconfigured. NASA engineers say that the July near drowning and Saturday’s water problem are entirely different issues.
At least two more spacewalks are needed to complete repairs to the cooling loop, and one has been planned for Christmas Day, which, if conducted, would make it the first spacewalk ever done on the holiday. However, it could be dangerous to allow the space station to rely on only one cooling loop indefinitely, NASA has elected to have ISS astronauts continue to conduct the dangerous repairs as soon as their suits are available.
By Marisa Corley