by Scott Kelly
The surface of the planet is 250 miles below my face and whizzing by at 17,500 miles per hour. It takes the ground about ten minutes to tell Kjell and me to go outside the hatch, where we can move around better, so I can check over Kjell’s suit for a leak. In the cold of space, a leak would look like snow shooting out of the backpack of the suit. If I don’t see snowflakes, we may be allowed to continue.
I grab both the handrails on either side of my head, getting ready to pull myself out. The airlock’s hatch faces the Earth, which would seem to be the direction we would call “down.” When we trained in the pool, the hatch was facing toward the floor, which always felt like down. Though I was neutrally buoyant in the pool, gravity still forced me toward the center of the Earth, providing a clear sense of up and down. For the hundreds of hours we practiced for this spacewalk, I got used to the idea of this configuration.
Once I’m about halfway through the hatch, though, I have a transition in perspective. Suddenly I have the sensation of climbing up, as if out of the sunroof of a car. The large blue dome of Earth hovers over my head like some nearby alien planet in a sci-fi film, looking as if it could come crashing down upon us. For a moment, I’m disoriented. I’m thinking about where to look for the attachment point, a small ring where I will hook my safety tether, but I don’t know where to look for it.
Like any highly trained pilot, I know how to compartmentalize, to push thoughts out of my mind that aren’t helping me to complete the task at hand. I focus on what is immediately in front of me—my gloves, the handrail, the small labels on the outside of the station I’ve familiarized myself with through countless hours of training—and ignore the looming Earth above and the feeling of disorientation it creates. I don’t have time for it, so I set it aside and get to work. I take the hook from my safety tether off my mini-workstation, a high-tech toolholder attached to the front of my spacesuit, and secure it to one of the rings just outside the airlock, checking to make sure the hook is in fact closed and locked with complete certainty. Like putting an airplane’s landing gear down before landing, this is one of those things you absolutely do not want to screw up.
During my last long-duration mission on ISS, two of the Russian cosmonauts, Oleg Skripochka and Fyodor Yurchikhin, did a spacewalk together to install some new equipment on the outside of the Russian service module. When the two of them came back inside, they both looked shaken, Oleg especially. I assumed at first his reaction was to being outside for the first time, and it wasn’t until this yearlong mission that I learned all the details of what had happened that day: during their spacewalk, Oleg had become untethered from the station and started to float away. The only thing that saved him was hitting an antenna, sending him tumbling back toward the station close enough to grab on to a handrail, saving his life. I’ve often pondered what we would have done if we’d known he was drifting irretrievably away from the station. It probably would have been possible to tie his family into the comm system in his spacesuit so they could say good-bye before the rising CO2 or oxygen deprivation caused him to lose consciousness—not something I wanted to spend a lot of time thinking about as my own spacewalk was approaching.
The U.S. spacesuits include simple propulsive jets we could use to maneuver ourselves in space in case our tether breaks or we screw up, but we would not want to rely on them or, truth be told, try them out at all. The only way we practiced using the jet packs during our training was with virtual reality simulations, during which astronauts sometimes ended up running out of fuel or missing the space station altogether. I’m acutely aware that if I become detached and run out of fuel and the station is just one inch from my glove tips, it may as well be a mile. The result will be the same: I will die.
Once I’m certain my tether is secured, I remove Kjell’s tether from me and attach it to the outside of the station as well, being just as careful to double-check it as I was with my own. Kjell starts handing me bags of equipment we will need for our work, and I secure each of them to the circular handrail outside the airlock. Once we have everything we need, I give Kjell the go to exit. The first thing we do once we are both outside is our “buddy checks,” looking over each other’s suits from head to toe making sure everything is in order. Tracy talks us through it from mission control, telling me step-by-step how to check Kjell’s PLSS (portable life support system, the “backpack” we wear with the spacesuit) for signs of water having frozen in the sublimator. It looks completely normal—there are no snowflakes, I’m happy to report to the ground. Kjell and I both breathe a sigh of relief. Our spacewalk will proceed. (Later we would learn that some of the engineers wanted to call off the spacewalk and the lead flight director overruled them.) We go over each other’s helmet lights, helmet cameras, mini-workstations, jet pack handles, checking to make sure everything is properly stowed. One of Kjell’s jet pack handles is not—it was partially deployed while Kjell was on his way out of the airlock—and one of mine was as well. After fixing them, we check our tethers one more time. You can’t be too careful with tethers. Nearly five hours after getting into our spacesuits, we are ready to get to work.
—
FOR NEARLY as long as human beings have been going into space, we have been determined to climb out of the spacecraft. It’s partly just to achieve the fantasy of a human being floating alone in the immensity of the cosmos, nothing but an umbilical connecting him or her to the mother ship. But spacewalks are also a practical necessity for exploration. The ability to move from one spacecraft to another, to explore the surfaces of planetary bodies, or (especially relevant to the International Space Station) to perform maintenance, repairs, or assembly on the exterior of the spacecraft—all are crucial to long-term space travel.
The first spacewalk was carried out in 1965 by cosmonaut Alexei Arkhipovich Leonov. He opened the hatch of his Voskhod spacecraft, floated out on an umbilical, and reported to Moscow: “The Earth is absolutely round”—probably to the dismay of flat-earthers everywhere. It was a triumphant moment for the Soviet space program, but after twelve minutes, Alexei Arkhipovich found that he could not get back through the hatch. Due to a malfunction or poor design, his spacesuit had inflated to the point that he could no longer fit through the narrow opening; he was forced to let some of the precious air out of his suit in order to struggle back through. Doing so caused the pressure to drop so much he nearly passed out. This was not an auspicious beginning to the history of spacewalks, but since then more than two hundred people have successfully suited up to float out an airlock into the blackness of space.
While some of the challenges of spacewalks have gotten easier, they are no less dangerous. Just a few years ago, astronaut Luca Parmitano’s helmet began filling with water while he was outside, raising the terrifying specter of an astronaut drowning in space. Spacewalks are much riskier than any other part of our time in orbit—there are so many more variables, so many pieces of equipment that can fail and procedures that can go wrong. We are so vulnerable out there.
As pilot and commander of the space shuttle, I never had the chance to do a spacewalk. The mission specialists went through the hundreds of hours of training necessary to work outside the spacecraft while I trained to fly and command the mission. For most of the shuttle era, those of us designated as pilots knew that, because of this division of labor, we would never have the chance to put on a spacesuit and float out into the cosmos. A shuttle could return safely with a missing or injured mission specialist, but a missing pilot or commander would be much more problematic. But we are now in another era of spaceflight, and this mission on ISS has given me the chance.
Getting ready to go outside takes a great deal of time. We plan in advance as thoroughly as we can what we will do and in what order, to minimize problems and to maximize efficiency and performance. We prepare the suits, check and double-check all of the components that will keep us alive in the vacuum of space, and organize and prepare the tools we will use—custom-designed for use in zero gravity with our bulky gloves
.
I’ve been up since five-thirty this morning and have been hurrying to stay ahead of the timeline all day. I got into a diaper and the liquid cooling garment we wear under the spacesuits, like long underwear with built-in air-conditioning once it’s connected to the suit. Then I ate a quick breakfast I’d laid out the night before to save time and made my way to the airlock to start getting suited up. My goal was to be out of the airlock early—my philosophy is that for complicated jobs, if you aren’t ahead of schedule, you’re already behind.
Kjell and I spent an hour breathing pure oxygen to reduce the amount of nitrogen in our blood so we wouldn’t get the bends (decompression sickness). Kimiya is the intravehicular crew member (IV) for this spacewalk, responsible for helping us get dressed, managing the procedure for prebreathing oxygen, and controlling the airlock and its systems. His tasks might seem mundane, running down a checklist with hundreds of steps, but his job is critical for Kjell and me. It’s practically impossible to get in and out of a spacesuit without help, and if Kimiya makes even the smallest mistake—puts on my boot incorrectly, for instance—I could die a horrible death. My suit includes a life support system that keeps oxygen flowing, scrubs the carbon dioxide that I exhale, and keeps cool water flowing through the tubes covering my body so I don’t get overheated. Although weightless, the suit still has mass. It’s also stiff and bulky, making it difficult to maneuver.
I slid into the pants of the suit, and Kimiya helped me squeeze into the hard upper torso. Nearly dislocating my shoulders and hyperextending my elbows, I pushed my arms into the sleeves and my head through the neck ring. Kimiya connected my liquid cooling garment umbilical, then sealed the pants to the torso. Each connection between pieces of the suit is critical. The last step was to put my helmet on. My visor had been fitted with Fresnel lenses to correct my vision without me having to wear glasses or contacts. Glasses can slip, especially when I’m exerting myself and sweating, and I can’t adjust them when I’m wearing my helmet. Contact lenses would be an option, too, but they don’t agree with my eyes.
Once we were suited up, Kimiya floated us into the airlock—first me, then Kjell—allowing us to conserve our energy for what was to come. We floated and waited for the air to be pumped out of the airlock and back into the station. Air is a precious resource, so we don’t like to vent it out into space.
Tracy’s voice breaks the silence: “All right, guys, with Scott leading, we will begin translating out to your respective work sites.”
By “translate,” she means to move ourselves, hand over hand, along a path of rails attached to the outside of the station. On Earth, walking is done with the feet; in space, especially outside the station, it’s done with the hands. This is one of the reasons why the gloves of our spacesuits are so critical.
“Roger that,” I tell Tracy.
I translate out to my first work site, on the right side of the giant truss of the space station, occasionally looking back to see how my tether is routed and making sure it doesn’t get snagged on anything. At first, I feel like I’m crawling hand over hand across a floor. I’m immediately struck by how damaged the outside of the station is. Micrometeoroids and orbital debris have been striking it for fifteen years, creating small pits and scrapes as well as holes that completely penetrate the handrails, creating jagged edges. It’s a little alarming—especially when I’m out here with nothing but a few layers of spacesuit between me and the next strike.
Being outside is clearly an unnatural act. I’m not scared, which I guess is a testament to our training and to my ability to compartmentalize. If I were to take a moment to ponder what I’m doing, I might completely freak out. When the sun is out, I can feel its intense heat. When it sets, forty-five minutes later, I can feel the depths of the cold, from plus to minus 270 degrees Fahrenheit in minutes. We have glove heaters to keep our fingers from freezing but nothing for our toes. (Luckily, my ingrown toenail has healed after a few weeks without any further intervention or this would be even more uncomfortable.)
The color and brilliance of the planet, sprawling out in every direction, are startling. I’ve seen the Earth from spacecraft windows countless times now, but the difference between seeing the planet from inside a spacecraft, through multiple layers of bulletproof glass, and seeing it from out here is like the difference between seeing a mountain from a car window and climbing the peak. My face is almost pressed against the thin layer of my clear plastic visor, my peripheral vision seemingly expanding out in every direction. I take in the stunning blue, the texture of the clouds, the varied landscapes of the planet, the glowing atmosphere edging on the horizon, a delicate sliver that makes all life on Earth possible. There is nothing but the black vacuum of the cosmos beyond. I want to say something about it to Kjell, but nothing I can think of sounds right.
My first task is to remove insulation from a main bus switching unit, a giant circuit breaker that distributes power from the solar arrays to the downstream equipment, so the unit can later be removed by the main robotic arm. This is a job that would normally require a spacewalk, but we are trying to use the robot arms to do more work.
Kjell’s first task is to put a thermal blanket on the Alpha Magnetic Spectrometer, a particle physics experiment. It’s been sending back the kind of data that could alter our understanding of the universe, but it needs to be protected from the sun if it’s going to continue doing its job—it’s getting too hot. The spectrometer was delivered to the station by the last flight of Endeavour in 2011, which was commanded by my brother. Neither of us would have guessed five years ago that I would be leading a spacewalk to extend its lifespan.
The Hubble Space Telescope and other instruments like the AMS have transformed our understanding of the universe in recent years. We had always assumed that the stars and other matter we could observe—200 billion galaxies each with 100 billion stars on average—made up all of the matter that existed. But we now know that less than 5 percent of the matter in the universe is actually observable. Finding dark energy and dark matter (the rest of what’s out there) is the next challenge for astrophysics, and the AMS is searching for them.
Removing and stowing the insulation from the main bus unit is a relatively simple task for a spacewalk, but as with everything we do in zero g, it is harder than you would think—sort of like trying to pack your suitcase if it were nailed to the ceiling. The focus required to do even simple work in space is daunting, similar to the focus required to land an F-14 Tomcat on an aircraft carrier, or land the space shuttle. But in this case I have to maintain that focus all day, rather than only for a matter of minutes.
The three most important things to keep track of today are what I think of as the three T’s: tethers, task, and timeline. From moment to moment, I have to be aware of my tethers and whether they are properly attached. There is nothing more important to my continued survival. In the medium term, I have to focus on the task at hand and on completing it properly. And in the long term, I have to think about the overall timeline for the spacewalk—the scheduled sequence of tasks planned out to make the best use of our finite suit resources and our own energy.
When I finish removing the insulation and stuffing it into a bag, I get congratulations from the ground for a job well done. For the first time in hours, I take a deep breath, stretch as best I can in the stiff spacesuit, and look around. This would normally be a good time to break for lunch, but that’s not on today’s schedule. I can sip water through a straw in my helmet, but that’s it. I’m making good time and still have a lot of energy. We are going to be able to nail this spacewalk, I think to myself. As the day goes on, it will become clear that this is a false sense of confidence.
The next task for me is working on the end effector, the “hand” of the robot arm. Without it, we can’t capture and bring in the visiting vehicles that deliver food and other necessities to the U.S. side of the station. Once I’m secured in a foot restraint, I realize how lucky I am: rather than facing the blank exterior of an
ISS module, as spacewalkers usually do (and as Kjell is at this moment), I am facing out toward the Earth. I can watch the stunning view splayed out below my feet as the Earth goes by while I work, rather than having to turn around and look out the corner of my eye during the rare free moment. I feel like Leonardo DiCaprio at the bow of the Titanic, and I’m king of the world.
While I was training for this mission, I practiced greasing a replica of this end effector, using tools identical to the ones I’m using up here. While I practiced, I wore a duplicate of my spacesuit gloves. But the experience is still disorientingly different now that I, the grease gun, and the grease are all floating in space, the sun rising and setting spectacularly every ninety minutes, the planet spinning majestically underfoot. The grease gun is well designed, like a high-grade version of a caulking gun from a hardware store, but it’s awkward to use with the fat-fingered gloves of the pressurized suit. For several hours, I wield this cumbersome tool like a five-year-old with finger paint. The grease goes everywhere. Small beads of grease jump off the gun as if they have a will of their own to explore the cosmos. Some of them come right toward me, which could pose a serious problem; if grease starts to coat the faceplate of my helmet, I may not be able to see to find my way back in. This task is taking much longer than had been scheduled, and soon my hands are aching to the point where I start to think I might not be able to move them. Of all the things that are tiring about this spacewalk, the amount of effort it takes to manipulate the gloves is by far the worst. My knuckles are rubbed raw, the muscles beyond fatigued, and I still have a great deal left to do. I work with Kimiya as he precisely maneuvers the robot arm to place it exactly where I need it. I put grease on the end of a long wire tool and stick it into the dark hole of the end effector. I can’t see in there and can only hope the grease is going in the right place as I blindly feel around.