Without a doubt, the most awe-inspiring and visually stunning movie of 2013 was Gravity, a movie concerning space starring George Clooney and Sandra Bullock. In Alfonso Cuarón's film, both Clooney's and Bullock's characters are sent hurtling through space after their spacewalk goes awry following collision from space debris. Luckily for NASA, Saturday's spacewalk saw none of the complications Clooney and Bullock faced.
Saturday's spacewalk was the first of three planned missions to replace a faulty unit on the exterior of the International Space Station. Ten days ago, a flow control valve malfunctioned inside of a pump module which controls the external and internal temperatures of the ISS. After the initial malfunction, NASA attempted to fix the situation from the ground by rerouting the mechanism through a different valve.
While the solution worked temporarily, the situation was urgent enough that NASA elected to schedule a series of spacewalks to resolve the issue. The urgency to make the repair stems from the fact that the ISS is about to reach the point in the year where it receives the most direct sunlight, which runs from December 30 to January 9 this year. During this time, the ISS must perform barrel rolls (hopefully by tapping Z twice) in order to avoid overheating. Due to these evasive maneuvers, spacewalks and cargo shipments are not permitted, and hence the urgency of the situation.
Originally, the astronauts were simply supposed to prep the pump module for module. Astronauts Rick Mastracchio and Mike Hopkins were able to finish the prep work in 3 hours, though, and were given permission to actually remove the module with their remaining 3.5 scheduled hours.
Leaving the astronauts out much longer than necessary was a potentially difficult decision for NASA, seeing as Hopkins was wearing the same suit which sprung a water leak last June when worn by Italian astronaut Luca Parmitano. Luckily for NASA and Hopkins, the repairs made to Parmitano's suit held up and were of no concern.
The only concern which did occur during the spacewalk had to do with temperature control: “The only issue that I personally am having is it's very, very cold,” stated Mastracchio. In particular, it was Mastracchio's toes that were cold. While Houston was able to warm Mastracchio's little piggies by blowing warm air into his boots, Mastracchio ultimately called it quits 1.5 hours early due to the chilly conditions.
.@Nester540 It's +150 in the sun, and -120 in the shade - Centigrade! A wicked place to work.
— Chris Hadfield (@Cmdr_Hadfield) December 21, 2013
The situation faced by Mastracchio and Hopkins Saturday was not unique. In 2010, astronauts Doug Wheelock and Tracy Caldwell Dyson performed an almost identical procedure to repair the ISS's cooling system. Due to their prior experience, Wheelock and Dyson were in Houston aiding Mastracchio and Hopkins during the repair efforts: "It's a little bit [of] a different failure we're facing this time around, but the spacewalks to remove the old pump module and replace it with a new spare is exactly the same as what we did in 2010. We've had a lot of lessons learned back then, and so we've implemented those changes into our procedure in the way that we prepare our suits and our tools, so we'll be ready to go on Saturday," stated Wheelock.
Wheelock also spoke about the familiarity of the situation for Mastracchio and Hopkins, adding, "We practice all of these skills, just rehearse them over and over again in the pool. The crew has done these particular skills. The skills are the same, but space always has surprises for us, especially when we go outside."
Space may have had some unusual surprises for Hopkins as this was his first-ever spacewalk. Fortunately, he had an experienced partner to help out. This spacewalk marked Mastracchio's seventh. His previous 6 spacewalks have totaled 38 hours and 30 minutes, placing him 14th on the lists of astronauts documenting the most hours of spacewalking.
The next spacewalk is scheduled for Monday, December 23rd, while the third is currently scheduled for Christmas. However, due to currently being ahead of schedule, the third walk may not be necessary. If it does occur, the spacewalk on December 25 will be the first spacewalk to ever occur on Christmas.
Images via YouTube