NASA astronaut Rick Mastracchio, who as of 2014 accumulated nine career spacewalks, during a 2010 spacewalk during shuttle mission STS-131. Credit: NASA
You’d be hardpressed to find somebody with more in-space spacesuit experience than Rick Mastracchio. The NASA astronaut is the fifth-most experienced spacewalker of all time, with 53 hours and 4 minutes of time working “outside” across nine excursions.
Mastracchio, who just landed a week ago from his latest, six-month expedition in space, wasn’t supposed to do any spacewalks at all during that time. All NASA spacesuits are being examined following a serious water leak that happened last summer. Contingency spacewalks can still go forward, however, and that’s what Mastracchio did. Three times, in fact. Two times to replace a malfunctioning ammonia pump, and once to swap out a failed computer.
On his first two extravehicular excursions during Expedition 38, Mastracchio accompanied Mike Hopkins, a first-time flyer. Astronauts receive hours of instructions in NASA’s Neutral Buoyancy Laboratory on spacewalks before going to orbit. Mastracchio, however, did have additional advice for Hopkins.
“The most important thing: go very, very, very slow. We train in a large swimming pool and the pool provides a lot resistance,” Mastracchio said in a brief interview with Spaceshippers carried live on NASA Television today (May 20). While water provides resistance, space does not, he added: “A little bit of a tug and it sends you moving quickly.”
NASA astronauts Rick Mastracchio (left) and Mike Hopkins work on their spacesuits around the time of two contingency spacewalks during Expedition 38 in December 2014. Credit: NASA TV
Hopkins and Mastracchio were supposed to have three spacewalks in December to fix the pump, but ended up completing in two. Mastracchio attributes that success to two factors: Hopkins’ inherent talent as a spacewalker, and the overall organization of “the ground” — the large teams helmed by Mission Control who came up with the procedures quickly for the astronauts on board.
There also was some luck involved, he acknowledged, because everything went relatively smoothly during the replacement. The disconnections and reconnections of ammonia lines, for example, involved a risk of leaks. The astronauts did face a brief shower of snowflakes during their final spacewalk in December, but after a brief decontamination by “baking off” the ammonia in the sun and remaining inside the airlock for a few extra minutes, returned to station without further incident.
Although six months gives astronauts time to plan out procedures and experiments, there are moments when things get more hectic. One of them was the arrival of the Dragon spacecraft before Mastracchio and Expedition 39 crewmate Steve Swanson were to do a spacewalk in April to replace a broken backup computer, known as a multiplexer/demultiplexer (MDM).
Expedition 38 astronaut Rick Mastracchio (NASA) works with the free-flying satellites called Synchronized Position Hold, Engage, Reorient, Experimental Satellites, (SPHERES) in the Kibo laboratory on the International Space Station. Picture taken in January 2014. Credit: NASA
First there was the time the astronauts needed to grab the spacecraft with the Canadarm2, a robotic arm on station. Also, Dragon carries time-sensitive life experiments on board that need to be stored quickly in a freezer, or be performed relatively quickly, lest the work be lost.
The packers for the spacecraft are pretty smart when it comes to priority experiments, Mastracchio said. Those tended to be near the front, making it easy for the astronauts to store them away or activate them, as needs required. “Those are very, very busy days when a cargo ship comes full of science,” he said, but called these times some of the most enjoyable days in orbit since there’s so much interaction with crewmates.
When asked what were some of the most memorable experiments while on station, Mastracchio mentioned a couple. One was SPHERES ( Synchronized Position Hold, Engage, Reorient, Experimental Satellites), free-flying satellites that were used in the Japanese Kibo laboratory. Mastracchio and his crewmates placed stereoscopic goggles aboard one of the SPHERES pair, which mapped the other and attempted to do navigation around it.
He also cited Antibiotic Effectiveness in Space-1, which is supposed to look at how well certain antibiotics perform against bacteria — which appear to be somewhat stronger in space than they are on Earth.