The first explorers who crossed the ocean in sailing ships didn’t blithely set off without considering the practicalities and logistics. Before they ever left land, they tried to figure out which kind of timber would hold up the best and what kinds of food would keep on a long voyage. They tried to reduce the risks and improve the chances of success by thinking through every aspect of the expedition, beforehand.
The ISS, too, is a testing ground, a place to consider the practicalities and logistics of even more ambitious expeditions. We’re trying to figure out two things: how to make a spaceship that’s fully self-contained so we can safely venture farther into the universe, and how to keep human beings healthy while doing that.
Because of all the exercise we do and because our diet is controlled—no deep-fried food, no alcohol, no sinfully rich cakes and cookies—most of us return to Earth in pretty good shape and with a lower percentage of body fat. But in space, things happen to our bodies that may or may not be bad for our long-term health. When I closed my eyes, for instance, I occasionally saw very faint bursts of light: cosmic rays—high-energy particles from some distant sun racing across the universe and striking my optic nerve like a personal lightning bolt. The flashes were right at the edge of perception, almost as if teasing me to detect them. A lot of astronauts experience this, and it’s not particularly bothersome, more just a minor visual event reminding you you’re not in Kansas anymore. But, of course, it’s related to radiation exposure. On Earth, the atmosphere and magnetic field provide some protection from the radiation of the sun and billions of other stars, but the ISS is constantly bombarded by high-energy particles. So far, there’s no evidence that astronauts have a significantly increased risk of cancer or cataracts, but we do absorb more radiation than we would at sea level, and it’s worth figuring out what to do about that.
Other anatomical changes associated with long-duration space flight are definitely negative: the immune system weakens, the heart shrinks because it doesn’t have to strain against gravity, eyesight tends to degrade, sometimes markedly (no one’s exactly sure why yet). The spine lengthens as the little sacs of fluid between the vertebrae expand, and bone mass decreases as the body sheds calcium. Without gravity, we don’t need muscle and bone mass to support our own weight, which is what makes life in space so much fun but also so inherently bad for the human body, long-term.
Finding out what causes these kinds of changes and coming up with ways to prevent and counteract them will be important in order to, say, get to Mars—a round trip would take two years at least. Turning up there and not being able to see anything would be a problem. Naturally, the best place to study physical changes related to long-duration space flight is on the ISS itself, so that’s an important focus up there.
About half of the scientific experiments our crew did were related to investigating what was happening to our own bodies in space. We ran all kinds of tests to gauge how much our hearts were shrinking, what was happening to our bone density and blood vessels, whether changes were occurring inside our eyes, and so on. We were, to a large extent, lab techs: we didn’t interpret data—usually we just collected it. For one experiment, for instance, I’d put a drop in one of my eyes, then Tom would tap my eyeball very gently 10 times with a small pressure gauge called a tonometer; the measurements and images were relayed back to Earth so experts could check out what was happening to the pressure inside my eyeball. Tom and I also did ultrasounds on one another’s eyes to get accurate images of the optic nerve, lens and cornea (luckily, I was told later that my eyes are just fine). We also performed several skeletal ultrasounds of one another’s spines and hands, remotely guided by experts on the ground, as well as cardiac ultrasounds, which are trickier to do.
It was really gratifying to have reached a skill level where I could get a good image of Tom’s heart and know that a scientist on the ground could actually figure out what, if anything, the image meant. Most of the human biological experiments we participated in outlasted our expedition; more astronauts will need to do those same experiments in order to have a scientifically meaningful sample size, and it will be years before we learn the results.
We know before we go to space that we are going to be human guinea pigs, but we are highly informed, consenting human guinea pigs. Scientists and doctors come to NASA to pitch their tests and experiments to us, explaining what they’re trying to find out and why, and after these briefings, which take days, we’re left with hundreds of pages of information and decisions to make about which experiments to sign up for. Medical scientists will do whatever you allow them to—in the 1990s, crews launched with heart catheters and rectal probes—because there’s never enough data and there’s never a big enough sample of astronauts to study. I signed up for all the experiments except the ones that required biopsies; I’m willing to inconvenience myself and work hard, but not to give away pieces of my flesh.
Urine, however, is another matter, and all of us spent a great deal of time on Station collecting it. The ISS toilet is located in a white booth and consists of a long hose coming out of the wall with a yellow funnel to pee into, just like a mini-urinal. There are foot and hand holds, so you don’t float away; you grab the hose, which is attached to the wall with a bit of Velcro, pop the lid off it and wait for it to start drawing air. There’s about a 15-second spin-up cycle, and you want to be sure there’s good suction or there will be quite a mess to clean up. Even if you pee directly into the tube though, there will always be a few drops left on the funnel. Tracy Caldwell Dyson, who’s been singing with me in Max Q, the all-astronaut band, for more than a decade, left an inspirational message on the wall the last time she was on Station: “Blessed are those who wipe the funnel.” There’s an impressive range of things you can use for that purpose: tissues, baby wipes, gauze, Russian dry wipes and disinfectant wipes. You put whatever you used in a bag, clean your hands with a baby wipe and stick that in the bag too, pinch it closed, put it in the garbage and you’re done.
Unless, that is, you’re taking part in an experiment of some sort and peeing for science, as astronauts are about 25 percent of the time. In that case, you need to cart some paraphernalia into the bathroom. If all you’re doing is testing pH, to check on organ function and body chemistry balance, it’s not so bad. You get yourself set up with a data chart, a color chart, a Q-tip, a pH strip, wet wipes and a little bag—all of which, naturally, are prone to drifting away (for some reason, there is no sim at JSC where you learn to corral a bunch of small, weightless objects while also holding a hose and attempting to relieve yourself). This is where the ingenuity born of decades of sophisticated technical training came into play: After a couple of days I figured out that I could stick all the smaller items into one of the bathroom books, which made a decent little trap. Then, after I was done, I could use the Q-tip to swab a few drops off the funnel, rub the Q-tip on the pH strip, match the strip against the color chart to get a valid reading, enter the data on the chart, then clean up as usual. The first time took 15 minutes, but with practice I was able to get it down to 5 minutes.
Collecting a urine sample was quite a bit more complicated and required a container of test tubes, a whole cleanup kit and a big plastic bag that looked just like a hot water bottle, only at one end there was a condom and, at the other, a long, thin hypodermic-looking tube capped with a blue rubber diaphragm. Already inside the bag was a chemical that needed to be mixed with the urine sample for the whole exercise to work. Full disclosure: I’m not entirely sure how female astronauts go about this, but as will become clear shortly, it’s almost certainly different than the way male astronauts do it.
First you need to stretch that hot water bottle-esque bag to be sure the little septum between the condom and the bag is as open as it can be, so the force of your pee will overcome the little one-way valve and fill up the bag rather than squirting back out and all over you, all over the walls, all over—you get the picture. Once the bag is filled, you put it in a Ziploc bag just in case it
leaks (at least once, it will) and shake it vigorously to make sure the chemical is mixed well with the urine.
At this point, when your hands are covered with blobs of urine and drops are floating around the bathroom, too, it’s usually helpful to remind yourself that you are doing all this in the name of scientific inquiry. Take a minute to clean yourself up and while you’re at it, grab a disinfectant wipe—surely you’ve got a free hand!—and clean the ceilings and walls, too.
All right, it’s time to fill the test tubes: depending on the experiment, sometimes you’ll only need to fill one, but typically it will be five. With a Sharpie, label each test tube with the time, date and your name. While you were shaking up the urine and chemical, bubbles formed in the sack, so now you need to spin it—gently!—like a centrifuge, so all the bubbles collect at the condom end. Then, through the little blue diaphragm, fill each test tube three-quarters full so there’s room for expansion after the sample freezes. Luckily, the tubes have Velcro on them so you can stick them to the wall. Once you’re done, seal up the big bag in the Ziploc, burping out any air, and clean yourself up again.
Now it’s time to fire up the bar code reader and bar code the test tubes, then put them in a mesh bag and place it in a special -140 degree freezer, called a MELFI. It looks like something you’d see in a morgue, complete with sliding drawers that contain long, rectangular boxes. They’re so cold that you have to wear special white gloves to handle them, and you can only keep the freezer open for 60 seconds, so you don’t compromise any of the other biological samples already in there. That’s tricky, though, because as soon as you open a box, a bunch of previously filled mesh bags come floating out. Like a beekeeper, you’ve got to shove them back in the hive along with the new bag and close that drawer cleanly—if even a tiny corner of fabric gets caught, the thing will jam. This is actually something we practiced doing on the ground, where, of course, nothing was weightless and trying to escape. Here comes the fun part (seriously): as you slide the drawer back in, it flushes out ice crystals that envelop your upper body like the coolest cloud.
Take off your gloves: you’re all done! And the whole procedure only took 40 minutes or so. Now you know how much time you’ll need to budget every single time you pee over the next four days, which is typically how long you have to give samples for any one experiment. Oh, and don’t forget to coordinate bathroom trips with crewmates who are also urinating for science—the MELFI can only be opened once every 45 minutes.
The science we were doing didn’t just involve urine juggling, though. Our crew was also testing a device called Microflow, a toaster-sized box that uses fiber optics and a laser to analyze blood samples and provide readings in less than 10 minutes—a wonderful, portable technology that could be a godsend in rural communities. We also worked on RaDI-N 2, a Canadian experiment to detect and measure the levels of neutron radiation in different parts of the ISS. I liked it because it was both simple and elegant: test tubes filled with clear polymer gel were placed in different locations on Station—when a neutron struck a test tube, it created a visible gas bubble. A reader then analyzed the tubes to determine which modules of the ISS were getting higher doses of radiation. (It turns out that some modules are better shielded than others, though it’s not yet clear how big a problem this is or what the long-term health implications are for astronauts and cosmonauts.)
Some of my favorite experiments were the ones attempting to answer really big questions like, What’s the universe made of? The Alpha Magnetic Spectrometer, mounted on the Station’s exterior, is collecting dark matter and high-energy particles to try to provide an answer. Another experiment is looking at the behavior of nanoparticles and how they coalesce without the weight of gravity. Most of the 130 experiments on board are ones that simply cannot be done on Earth: we’re there to make sure that scientists on the ground get the information they need.
It’s a big responsibility and an honor to work in that huge orbiting laboratory. Figuring out how to support life in the hostile environment of space has resulted in thousands of down-to-earth spin-offs, from temperature-regulating underwear to heart pumps that rely on Shuttle fuel-pump technology. The concrete benefits and by-products of the science we do in space have touched fields from agriculture to medicine to robotics. Data gathered on the Shuttle and ISS help power Google Maps; experiments with different dietary and exercise protocols have revealed how to ward off, permanently, one debilitating type of osteoporosis; the robotic machinery now used inside the parts of nuclear power plants that are too hazardous for humans is a direct descendant of Canadarm2—the list goes on and on.
A lot of times the work isn’t glamorous, but that’s okay. The workplace itself is, after all, in a pretty great location.
Every morning on the ISS, NASA sent us a schedule of what we were supposed to accomplish, broken down into five-minute increments. Almost every day had the same three components. First, some basic maintenance—checking systems, cleaning up, inspecting equipment for wear and tear, that sort of thing. Sometimes, there were scheduled repairs, like overhauling the communications system. Another part of each day was devoted to science: I’d be assigned to work on X experiment for Y minutes while Tom was busy with Y experiment for X minutes, and so on. Often we were in different modules, working on completely unrelated tasks. And finally, there was downtime.
It was a regimented existence but, in many respects, easier duty than I’d had on Earth. I wasn’t constantly on the road; I wasn’t endlessly training for contingencies. There was a bit of on board training—practicing robotic skills on a simulator or Canadarm2, conferencing with instructors to prepare for an upcoming vehicle rendezvous—but overall, there were fewer demands on our time, and sometimes we were even able to complete tasks faster than anyone on the ground thought we would.
So what do you do on the ISS if you’re 10 minutes ahead of schedule? Well, you can look out the window—I viewed every spare minute on the ISS as a good opportunity to drink in the view. Another thing we like to do with any unlooked-for free time: take advantage of weightlessness. It was not uncommon to come across a crewmate pirouetting, spinning or flipping around just for the fun of it. We also liked to play with water. Someone would carefully squirt a swirling ball of water out of a drink bag and then, like kids chasing a soap bubble, we’d move around this floating ball and blow on it, gently. If we weren’t careful, of course, it would break apart and make a giant mess; the forced airflow that draws objects toward an air inlet made steering the water bubble more challenging, and sometimes the only way to avoid disaster was to quickly slurp it up. A few times we used dental floss to corral and spin the ball, laughing and chasing it until it got too close to a wall and we had to smother it and soak it up with a towel.
If we felt like living dangerously, we’d play this game with a ball of coffee or juice—you risked a messier mess, but the colors were good for arty photographs. We also took pictures of balls of water, trying to capture our own upside-down reflections in them. The pepper that we put on our food is suspended in oil so it doesn’t fly all over and cause sneezing fits, and once I very cautiously squirted some pepper oil into a floating water ball, creating a delightful sphere within a sphere, held apart by their natural repulsion.
Another game was created spontaneously during one short break in the schedule. The ground support teams use bubble wrap to pack fragile items for launch, so after we unpacked an experiment we put the bubble wrap in a big duffel bag at the farthest end of the Japanese laboratory, where it wouldn’t be in the way. On a semi-regular basis, then, we had to float all the way to a far corner of the Station to deal with leftover bubble wrap. A full-length traverse of the ISS is a natural excuse for testing our prowess as space-movers—efficient elegance is a real source of pride for most astronauts, myself included—and soon we’d made a game of it: Who could fly from the Node 1 dining table to the bubble wrap bag, deposit a scrap of wrap securely and get back the fastest? After a while, we actually started hoarding b
ubble wrap during the day so we could have timed heats at dinner. Watching each other careen down to the Japanese module, arms and legs akimbo, clutching a small, bubbly square of plastic, then swing madly around the corner only to reappear several seconds later, frantic to fly across the finish line in first place, made us laugh every time. I remember being inordinately proud of completing the trip in 42 seconds one day.
There was scheduled free time, too, at the end of most days, and we had a reduced workload on the weekends. Mindful of the need to provide some leisure activities, the space agencies make sure there are DVDs and books on board. There are also musical instruments: a keyboard, ukulele, didgeridoo and guitar. National pride compels me to report that the guitar is a Larrivée, named after its Vancouver maker, Jean Larrivée. Getting it on Station wasn’t as simple as running into the factory and grabbing one: everything we take up has to be tested to ensure it doesn’t emit too much electromagnetic radiation and isn’t off-gassing chemicals, such as benzene, that would be dangerous to inhale in an enclosed space.
That guitar tested me, too. Weightlessness affected the way I played chords: at first my hand overshot the mark, anticipating resistance where none existed, and missed the frets. It took me a while to get the hang of it. On the plus side, I didn’t need a strap; the guitar just hovered in front of me, though I did need to brace it against my body to stop it from escaping altogether. One thing remained the same, though. Music sounded just like it does on Earth, despite the whirs and clunks of the fans and pumps, the creaks and snaps of expanding metal as we went in and out of sunlight. Sometimes the background noise was so loud I felt like I was playing in the back of a bus; it turned out that the best place to make music was my own sleep station. Tom and Roman also play guitar, so most evenings you could hear melodies emanating from one sleep pod or another, like music from a nearby campfire.