It was the night of December 20 and NASA Astronaut Mike Hopkins couldn’t sleep.
The next day he’d be making his first space walk, stepping out of the airlock to replace a refrigerator-sized piece of equipment on the outside of the International Space Station.
“The night before, all your training is done,” Hopkins says. “You’re prepared, you’ve got your tools ready, your suit’s ready, it’s really just a matter of now going out and executing. Yet it’s very difficult to get to sleep.”
He was just about halfway through a 166-day stint on the ISS.
Hopkins, 45, grew up near Lake of the Ozarks in Missouri. He attended the University of Illinois, where he studied engineering and captained the football team, before getting his masters at Stanford University. From there he joined the Air Force. The
n, in July 2009, NASA selected Hopkins as one of the 14 members of the 20th astronaut class.
He finished Astronaut Candidate Training in November 2011, which, according to NASA, includes “scientific and technical briefings, intensive instruction in International Space Station systems, Extravehicular Activity (EVA), robotics, physiological training, T 38 flight training and water and wilderness survival training.”
But the night before the spacewalk, he fell back on his days of captaining the Fighting Illini: When you’ve got a big game the next day, you have to keep your mind from mentally rehearsing the day’s performance.
So, as an astronaut does, he watched the finest in science fiction television: an episode of the cult hit “Firefly.”
Then the next day came. It was time to perform.
The prep process is a long one. Knowing that he wouldn’t be able to eat once he got his space suit on, Hopkins loaded up on cereal, fruit, and granola bars. After eating comes the clothing.
It takes four to five hours for an astronaut to get suited up and out the door. You don three layers of apparel. First you put on a pair of long underwear and breathe through a mask supplying pure oxygen — this prevents you from getting dizzy when air pressure changes. You add a tube-filled cooling garment to keep you chill during the whole process. Then comes the 300-lb. suit.
That’s where the whole outer space thing comes in handy.
“The microgravity makes doing some things harder,” Hopkins says, “but sometimes it makes it a little bit easier as well — once you have those pants on, it makes getting into the upper torso a little easier.”
After connecting the suit, you put the gloves and helmet on. Then more oxygen. You gather up all your tools for the job. You put on a safety pack, which is like a jet pack, just in case you drift away from the station while you’re working.
You head into the airlock, closing the hatch behind you. You pump all the air back into the station, turning the airlock into a vacuum. This takes a while, since you have to clear your ears and check your equipment and make sure there aren’t any leaks.
Then you crank the handle of the outer hatch, take it into an unlock position, release the latching mechanism, and let the hatch pop in and slide up.
You float out.
“All of a sudden you look out there and there’s nothing between you and the Earth,” Hopkins says. “It just takes your breath away.”
That’s when the training — done in a zero-gravity-mimicking pool back on Earth — kicks in.
“It’s like, ‘OK, I’ve got a job to do here,'” Hopkins says.
Outside, Hopkins works with his colleague Rick Mastracchio to replace a failed pump module on the side of the International Space Station. It’s a refrigerator-sized unit that circulates a coolant around the station, allowing for all the computers (and experiments) to run at their fullest capacity.
Once you’re outside, you have to be very deliberate with your movements, Hopkins says. That 300-lb. suit might not weigh anything in microgravity, but “that mass, once it’s going in one direction, it wants to keep going in one direction,” he says.
Because of that, you have to be controlled and methodical with the way you move, which can be difficult, given that being in a spacesuit is like wearing the most gigantic parka you can find and wearing the thickest sky gloves you can get your hands in.
Aside from the microgravity and the space suit, the job is pretty straightforward: Hopkins and Mastracchio disconnect the fluid lines and electrical lines to the failed unit, undo the bolts, and then grab the backup unit attached to the ISS and install that.
They started the job on the 21st and would finish it on the 24th.
“You just start walking through the procedures that you’ve trained in,” Hopkins says, “and all of a sudden it’s seven and half hours later and you’re coming back in.”
Back inside the station, it’s the reverse of the earlier process: unsuiting.
Replacing the cooling unit, Hopkins explains, is part of one of an astronaut’s main three duties: science, maintenance, and exercise. The spacewalk was like keeping a house in order, the orbital equivalent of cleaning out the gutters.
But first and foremost, he and the rest of the ISS team are scientists, often acting as the eyes, ears, and hands of experimenters on the ground. The third duty is exercise. Since microgravity does weird things to the human body, every astronaut schedules at least an hour of exercise per day.
Then there’s downtime: communicating with his wife and sons back home, updating social media, and taking pictures.
“The vantage point of seeing the earth from 260 miles up never gets old,” Hopkins says. “You can see these clouds from the horizon, from the rim of the Earth. They stand up out in the atmosphere.
The oceans and the mountains and the deserts, the way the sand dunes form these amazing geometric patterns by the wind. It’s really incredible. The city lights at night. The storms, you see lightning from above. Then you get these scenes of the moon coming up — it takes your breath away.”
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