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Authors: Mary Roach

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Here’s how bad it got, as reported in NASA Contractor Report 3943: “Reportedly, astronauts aboard the current STS mission (41-F) have resorted to use of Apollo-style adhesive bags. On previous missions, clouds of fecal dust generated by the zero-gravity toilet have caused some astronauts to stop eating in order that they reduce their needs to use the facility.” The same report elsewhere pointed out that fecal dust was not merely disgusting, but could result in “an unhealthy growth of E. coli bacteria in the mouth,” as used to happen on board submarines plagued by sewage vapor “blowback.”

The macerator has long since disappeared, but escapees still occasionally plague the crews. The culprit these days is a phenomenon you will read about in space agency waste collection papers and, one hopes, nowhere else: “fecal popcorning.” Broyan gamely elaborates: “Because everything else is frozen, the material that’s going in, depending on how hard the stool is, has a tendency to bounce off the walls. You’ve seen the old air-pop popcorn machines? There’s an air flow in there and it’s kind of circulating. That material’s just floating around in the air stream, and it tends to come back up the tube.” Howdy, doody.

Fecal popcorning is the reason Space Shuttle toilets were equipped with rearview mirrors. “We ask them to take a look back there as they shut that slider,” Broyan says, “in case there’s a piece that’s on its way up the tube.” Fecal popcorning is the gateway phenomenon to fecal decapitation. You do not want fecal decapitation taking place aboard your ship. If a crew member closes the sliding gate at the top of the toilet transport tube just as a popcorning piece is crowning, the slider gate may decapitate it on its way shut. This is a heinous scenario for two reasons. Any material smeared on the top side of the slider is sharing the cabin along with the crew, and, quoting Broyan, “they’re going to smell it.” Also, the smearage on the underside will freeze-dry the slider gate shut. Now the toilet’s out of order, and everyone has to use the shuttle’s contingency fecal waste collection system: the Apollo bag. If you’re the boob responsible, you are in for some blowback from your crewmates.

 

THERE IS NO WAY to anticipate a phenomenon like fecal popcorning. Some things you can’t know until you get into orbit. That’s why toilets, like everything else that flies in space, get hauled up on a parabolic flight for testing. In this case, the testing poses unique challenges.

Along these lines. Late yesterday afternoon, I got the idea that I wanted to try out the Space Shuttle training toilet. I was already scheduled to meet Broyan and Weinstein and my escort from the public affairs office at noon the next day. Nine A.M., absolute latest I can do, said my colon. I called Gayle Frere, my public affairs escort, to try to explain my dilemma and reschedule for first thing in the morning. I caught her at her grandson’s graduation, where she had to yell over the noise. I pictured her husband turning away from the festivities to ask what was going on. I imagined Gayle shouting into his ear. It’s that writer. She wants to crap in the shuttle toilet! I apologized and quickly hung up.

My meandering point being that to schedule an evacuation even within a matter of hours can be awkward. Imagine trying to do so on cue within a twenty-second window of weightlessness. Retired NASA food scientist Charles Bourland was once on board a parabolic flight with a group of engineers testing a zero-gravity-toilet prototype. The toilet had a partial screen set up around it, but Bourland could see the man. “It was number two,” he told me. “He was all primed to do his thing but couldn’t deliver at the appropriate time. There was a lot of joking and yelled words of encouragement,” though not from Bourland, who was fighting motion sickness while testing and sampling seventy-two new Skylab foods, including creamed peas and beef hash, and did not need any additional inducement to throw up.

Some of the testing done in weightlessness has been of a more exploratory nature. “As queer as it sounds, if you want to manage what comes out the back end, you gotta understand what it’s doing,” said Hamilton Sundstrand engineer Tom Chase, whom I ran into on a simulated moon expedition in the Arctic. Chase was wearing his spacesuit hat that week rather than his toilet hat, but he was game to chat shit. “For instance…” Chase began drawing on a pad of Hamilton Sundstrand graph paper balanced on his knee. “Without gravity to pull things straight, they tend to curl as they’re coming out.”* This was documented by NASA and Hamilton Sundstrand toilet engineers that day in a series of 16-mm films. Thanks to this work, aerospace waste collection systems engineers are not only aware of the curl, they know its range of curvature and most likely direction (backward). They know that the softer ones, up to a point, curl more. Why would they need to know all this? Because the curl can gum up the top of the transfer tube and compromise your air flow.

The films featured both male and female volunteers, the latter consisting of, said Chase, “some gals in the nurses’ corps.” The footage was classified as limited distribution but, according to Hamilton Sundstrand folklore, regularly traveled beyond its prescribed limits. Pretty much “anybody with a buddy in waste management design” saw them, said one of Chase’s colleagues. “They were very, very popular, those films.”

Eventually someone who saw the shit also saw the potential for it to hit the fan. “You can imagine the reaction,” said Chase—What if someone does a FOIA on these! (FOIA stands for Freedom of Information Act, whereby journalists and the public can request copies of unclassified government documents.) The films were destroyed. Chase waxed melancholy about their demise. He is part of the team that had been working on toilets for lunar missions. “It’s unfortunate because we were going through this phase here where it would be highly useful to us.”

Don Rethke said that the far trickier engineering problems—and thus the bulk of the footage—involved urination. For one thing, liquid tends to adhere to the body in space. “When gravity goes away,” says Rethke, “surface tension is the next physical force.” Even on a human hair, surface tension makes liquids cling. Rethke said that people with longer hair can, in zero gravity, hold two to three liters of water in their hair. NASA needed to know the extent to which pubic hair was compromising female “velocity potential.” (Scott Weinstein helpfully describes this as how easy it is to “write your name in the snow.”)

Chase began sketching again. “You don’t just urinate and get a perfect cylindrical outflow, if you’ve ever kind of observed what’s going on. With gals, there’s more in the way of getting a pure stream.” I.e., labia and pubic hair. And a weakened stream tends to break apart and form floating blobs. Then Chase told me something quite stunning. He said he’d known women who, while out hiking or backpacking, are “able to take their pants down to their ankles and kind of lean back against a tree and just by moving things around a little bit, getting some room there, be able to fire away and direct it.” There was a silence while I contemplated this new and life-changing information. Chase went on. “I’m telling you, women can pee harder than men. But you got to be willing to manipulate the anatomy. There’s just some ladies who are more comfortable exploring what is possible than other ladies.”

No kind of lady, regardless of comfort level, wants an audience of male toilet engineers and their cronies. Eventually the nurses got wind of what was happening and refused to participate in any more filming. Hamilton Sundstrand was forced to get creative. “One of the guys had a really hairy stomach,” said Chase, and here he leaned back in his chair and stuck out his belly. “If he went like this…” He placed a palm on either side of his stomach and pushed in toward his belly button, such that it was possible to imagine a vertical fold appearing in the flesh beneath his shirt. “…he got about the right look. So in zero G they could spray him with ersatz [urine] solution and film it and they could understand about the droplet formation.” Chase released his gut. “That’s good thinkin’.”

 

THERE ARE OTHER WAYS to test a zero-gravity toilet. “At NASA Ames Research Center, we have undertaken the task of developing human fecal simulants,” writes Kanapathipillai “Wiggy” Wignarajah in a 2006 technical paper. Wignarajah is surely the most sophisticated thinker in this realm, but he is not the first. Others before him—in, for instance, the commercial diaper industry—have employed brownie mix, peanut butter, pumpkin pie filling, and mashed potatoes. Wignarajah pooh-poohs these efforts, as none of these substances comes close to approximating, as he puts it, “how human feces will behave”—i.e., its water-holding properties and its rheology. Rheology, in food science, refers to the study of consistency. Consistency is determined by things like viscosity and elasticity. Food technologists have special equipment designed specifically to measure these things, and if they are smart, they will not lend them out to anyone at NASA Ames.

A simulant made from refried beans gets respectable scores from Wignarajah. Though the protein content is too high and thus the water-holding properties are off, the beans are said to look and behave so much like human stool that future visits to the tacqueria have, in my mind anyway, been forevermore altered. The bean-based simulant designers hail from “Umpqua,” and by this I assume Wignarajah means Umpqua Community College and not the Umpqua Bank or the Umpqua Indian Tribe.

The NASA Ames simulant blew the Umpqua dump out of the water. The recipe features eight ingredients, including miso, peanut oil, psyllium, cellulose, and “dried coarsely ground vegetable matter.” It may not taste as good as the Umpqua simulant but is in every other respect a vastly superior product. The main ingredient is the fecal bacteria E. coli, accounting for—as it does in real human feces—30 percent of the weight of the material. I don’t know whether the Ames toilet division has colonies of fecal bacteria on site—other than the ones inside the gut of every living employee—or whether they are procured by mail order. Wignarajah did not answer my email.

The one feature lacking in the Ames simulant was fecal odor. To be sure future toilets’ odor control measures are living up to expectations, Wignarajah plans to add malodorous compounds to the Ames simulant. Which leads one to wonder, Why bother with a simulant? If they need something that smells like the real thing, why not use the real thing? They do, but only at the very end. “Final testing can be completed with limited experiments on real human feces.” So powerful is the taboo against contact with human excrement that NASA researchers have, in days past, run simulations with monkey or dog feces playing the role.

 

ON THE FRONT of Broyan’s polo shirt is a patch from International Space Station Assembly Mission ULF2. The design incorporates various facets of the ISS toilet, arranged inside an oval toilet seat. A slogan reads, Proud to Be of Service.

Broyan has good reason to be proud, as do Weinstein, Chase, Rethke, Wignarajah, and everyone they work with. A successful zero-gravity toilet is a subtle finessing of engineering, materials science, physiology, psychology, and etiquette. As with Wiggy’s simulants, if just one element is missing, things don’t come out right. And few other technical failures have the power to so reliably and drastically compromise a crew’s well-being.

It’s possible the elimination issue has had even deeper ramifications. I interviewed a retired Air Force colonel named Dan Fulgham, who had been involved in the selection of the first Mercury astronauts. Colonel Fulgham told me the excretion conundrum was the main reason female pilots weren’t considered.* “We knew women were as good as men. We had female pilots all during World War II. They could fly fighters. They could fly bombers.” But they couldn’t use a condom-ended in-suit urine collection device. “The collection of body waste was a real issue logistically.” (The adult diaper was apparently not on anyone’s radar screen.)† “We were under the gun to get this thing underway,” Fulgham recalled. “So we said, ‘Let’s limit the amount of concerns we have.’”

If you read The Mercury 13: The Untold Story of 13 American Women and the Dream of Space Flight, you’ll see that the women pilots had other things working against them. Like Vice President Lyndon Johnson, who, rather than signing a letter to the director of NASA urging him to let female fighter pilots apply to become astronauts, wrote “Let’s stop this now!” across the bottom.

As mission lengths grew long enough to require a fecal strategy and crews grew to two-person, the female problem persisted. “The issue of privacy had been a big factor in NASA’s reluctance to include women as astronauts,” writes former NASA psychiatrist Patricia Santy of the Apollo-Gemini era. In Choosing the Right Stuff, Santy cites the development of the private space bathroom—“probably more than any other reason”—as the motivating factor behind NASA’s decision to allow female astronauts.

Were toilets a reason to exclude women, or an excuse? You would think that the passage of federal prohibitions on gender-based hiring discrimination would have been a more powerful impetus than a toilet door. The irony is that female astronauts are the more practical choice for spaceflight. On average, they weigh less, breathe less, and need to drink and eat less than men. Which means less oxygen, water, and food have to be launched.

Rather than keeping launch costs down by flying smaller, more compact humans, NASA chose to fly smaller, more compact pot roast and sandwiches and cake. Rarely has anything so cute been so loathed.

Packing for Mars
DISCOMFORT FOOD

When Veterinarians Make Dinner, and Other Tales of Woe from Aerospace Test Kitchens

 

On March 23, 1965, a corned beef sandwich from Wolfie’s delicatessen was launched into space. This particular branch of Wolfie’s was in Cocoa Beach, Florida, not far from the Kennedy Space Center. Astronaut Wally Schirra ordered it to-go and drove it back to Kennedy, where he convinced astronaut John Young to smuggle it on board the Gemini III capsule and surprise his crewmate Gus Grissom. Two hours into the five-hour-long flight, that is what Young did. The moment did not go entirely as envisioned.

GRISSOM: Where did that come from?

YOUNG: I brought it with me. Let’s see how it tastes. Smells, doesn’t it?

GRISSOM: Yes, [and] it’s breaking up. I’m going to stick it in my pocket.

YOUNG: It was a thought, anyway.

GRISSOM: Yep.

The “corned beef sandwich incident” became ammunition for NASA detractors at congressional budget hearings later that year. In the Congressional Record for July 12, 1965, one Senator Morse, pushing for a 50 percent reduction to the proposed $5 billion NASA budget, said Young had “made a mockery” of the entire Gemini science program, with its carefully measured intakes and outputs. Someone else asked NASA administrator James Webb how he could expect to control a multibillion-dollar budget if he could not control two astronauts. Young was given a formal reprimand.

The contraband Wolfie’s sandwich violated no less than sixteen of the formal manufacturing requirements for “Beef Sandwiches, Dehydrated (Bite-sized).” The requirements cover six pages and are set forth in the ominous phrasing of biblical commandments. (“There shall be no…damp or soggy areas.” “The coating shall not chip or flake.”) Moreover, the Wolfie’s sandwich exhibited Defect #102 (“foreign odor, e.g., rancid”) and Defect #153 (“breaks when handled”), among dozens of others but hopefully excluding Defect #151, “visible bone, shell or hard tendonous material.”

Food to eat in a space capsule must be the opposite of a Wolfie’s deli sandwich. It must be lightweight. Every extra pound that NASA launches into space costs thousands of dollars in fuel needed to lift it into orbit. It must be compact. The Gemini III capsule was no bigger than the interior of a sports car. Because of the strict size and weight limits, space food technologists were preoccupied with “caloric density”: packing the most nutrition and energy into the smallest volume of food. (Polar explorers, facing similar constraints and caloric demands but lacking government research budgets, pack sticks of butter.) Even bacon had to be squeezed under a hydraulic press and made more compact (and renamed the Bacon Square).

Compressed food not only took up less stowage—which is how children and aircraft designers say “storage”—space, it was less likely to crumble. To the spacecraft engineer, crumbs were more than a housekeeping issue. A crumb in zero gravity does not drop to the floor where it can be ignored and ground into the flooring until the janitor comes around. It floats. It can drift behind a control panel or into an eye. That’s why Grissom stashed the corned beef sandwich when he saw it was falling apart.

Unlike a Wolfie’s sandwich, a sandwich cube can be eaten in a single bite. Even a piece of toast will drop no crumbs if you are able to pop the whole thing into your mouth. Which you can do when your toast, as Young and Grissom’s did, takes the form of a Toasted Bread Cube. As an extra margin of safety, crumbs were held in check by an edible coating. (“Chill fat-coated toast pieces until they congeal…,” goes the recipe.)

The aerospace feeding teams—some Air Force, some Army, some commercial—devoted considerable effort to perfecting the coatings for their food cubes. One technical report outlines a Goldilocksian progression of formulas. Formula 5 was too sticky. Formula 8 cracked in a vacuum. But Formula 11 (melted lard, milk protein, Knox gelatin, cornstarch, sucrose) was thought to be just right. Except by those who had to eat it. “Leaves a bad taste in your mouth and coating on the roof of your mouth,” Jim Lovell complained to Mission Control during Gemini VII.

 

IT IS ONE THING to craft a lacquered sandwich cube that weighs less than 3.1 grams and resists fragmentation “when the sandwich is dropped from 18 inches onto a hard surface.” It is another to make this the sort of food a man will happily, healthily eat for weeks at a time. The missions of the Mercury and Gemini programs were, with one or two exceptions, of short duration. You can live on just about anything for a day or a week. But NASA had set its sights on lunar missions up to two weeks long. They needed to know: What happens to the digestive health of a man who consumes regular servings of lard flakes and pregelatinized waxy maize starch? How long could a human being survive on the kinds of foods being dreamed up by military test kitchens? More direly, how long would he want to? What does this sort of food do to morale?

Throughout the 1960s, NASA paid lots of people lots and lots of money to answer these questions. Space food R&D contracts were handed out to the Aerospace Medical Research Laboratories (AMRL) at Wright-Patterson Air Force Base and, later, the School of Aerospace Medicine (SAM) at Brooks Air Force Base. The U.S. Army Natick Laboratories drafted the manufacturing requirements, commercial vendors did the cooking, and AMRL and SAM inflicted them on Earth-bound test subjects. Both these bases constructed elaborate space cabin simulators where teams of volunteers were confined for mock spaceflights, some for as long as seventy-two days. Food was often tested at the same time as spacesuits, hygiene regimens, and different cabin atmospheres—including, delightfully, 70 percent helium.

Three times a day, experimental meals would be left by dieticians inside a pretend airlock. Over the years, recruits survived on all manner of processed and regimented aerospace foods: cubes, rods, slurries, bars, powders, and “rehydratables.” Dieticians weighed, measured, and analyzed what went in, and they did the same with what came back out. “Stool samples were…homogenized, freeze-dried, and analyzed in duplicate,” wrote First Lieutenant Keith Smith in a nutritional evaluation of an aerospace diet that included beef stew and chocolate pudding. You had to hope Lieutenant Smith kept his containers straight.

A photograph from this era depicts a pair of men in impossibly cramped conditions, wearing hospital scrubs and belts with some variety of vital-signs monitor. One young man sits hunched on the lower tier of a bunk bed so narrow and thin as to resemble a double-decker ironing board. He holds what appears to be a petit-four in his left hand, and a plastic bag containing four more layered cubes in his lap: dinner. A piece of tubing is taped to his nose. His roommate wears black Clark Kent glasses and a communications headset and sits at the kind of console that looked futuristic in 1965 and now looks Star Trek campy. The caption unhelpfully reads: “Space food personnel, 1965 to 1969.” Perhaps the writer had tried something more informative—“Testing the effects of miniature sandwiches on heart and breathing rates”—but could find no way to phrase it without compromising Air Force dignity.

Many of the shots are Before photos, luckless smiling airmen posed on the threshold of the SAM test chamber alongside dietitian May O’Hara before they step inside and she closes the hatch. O’Hara looks exactly as you imagine an Air Force dietician to look—neither over-nor underweight, well coiffed and nice-looking, though unlikely to have a profound effect on the heart rate and oxygen uptake of young Air Force recruits. O’Hara was a good Egg Bite. In a military news service article, she voices concern over the acceptability of the various space foods “day after day for 30 days or more.”

She seemed to be the lone voice of reason. Though cube foods were getting tepid ratings, their developers pressed on enthusiastically, relentlessly, hydraulically. They could not see that foods that require you to rehydrate them with your own saliva—by holding them “in the mouth for 10 seconds”—might be a spirit dampener on a weeklong flight. And they were. On mission after mission, sandwich cubes were, says retired NASA food scientist Charles Bourland, “some of the things that routinely came back.” (He means they were still on board after landing, not that they were regurgitated. I think.)

I telephoned O’Hara at her home in Texas, just after lunch on a weekday afternoon. She is in her seventies now. I asked her what she’d eaten. It was a dietician’s lunch, and a dietician’s answer, laid out like a cafeteria menu: “Grilled beef and cheese sandwich, grapes, and fruit punch.” I asked May whether the SAM simulator subjects often quit the studies early or busted out of the airlock to make a midnight run for Whataburger. They did not. “They were all just as cooperative as they could be,” said May. For one thing, she explained, they’d just come out of basic training. The prospect of a month with no physical demands more strenuous than chewing had a certain appeal. Plus, in exchange for volunteering, they were given their choice of Air Force assignment, rather than simply being sent someplace.

Over at the AMRL simulator, the volunteers were paid under-grads from nearby Dayton University. Perhaps because they were paid, or because Dayton was a Catholic school, these men too were compliant and generally well behaved. Though missing Communion* occasionally became an issue. One volunteer became so agitated that the scientists broke protocol and summoned a priest, who gave Holy Communion over closed-circuit TV and microphone. Into the pass-through port was placed a small portion of wine and a single Communion wafer, whose palatability probably scored on a par with more typical chamber fare.

One test diet scored even lower than the cubed foods. “It was milk shakes in the morning, lunch, and supper. And the next day, it was milk shakes in the morning, lunch, and supper,” says John Brown, the officer who had been in charge of the AMRL space cabin simulator. On a scale of 1 to 9, volunteers who lived on them for thirty days gave the food an average score of 3 (dislike moderately). Brown told me 3 probably meant 1: “The subjects filled out their forms telling you what you wanted to hear.” One subject confided to Brown that he and his fellow volunteers had been regularly dumping portions of their formula under the cabin flooring. Despite the diet’s unpopularity, the researchers evaluated no less than twenty-four different commercial and experimental liquid diet formulas. I once read an Air Force technical report that lists the desired attributes of edible paper: “Tasteless, flexible, and tenacious.” It’s how I imagine some of these space food guys.

Meanwhile, over at SAM, Norman Heidelbaugh was testing a liquid diet of his own devising. An Air Force press release called it the “eggnog diet.” May O’Hara described it as “sort of a powdered Ensure.” “That was really not acceptable,” she said with uncharacteristic bite to her words. Heidelbaugh himself seemed to leave a bad taste in people’s mouths.

Though it appeared that the science of nutrition was attracting a unique breed of gustatory sadist, other forces were at work here. It was the mid-sixties. Americans were enraptured by convenience and the space-age technologies that bestowed it. Women were going back to work, and they had less time to cook and keep house. A meal in a stick or a pouch was both a novelty and a welcomed time-saver.

That was the mindset that propelled one of the AMRL’s least popular liquid diets into a long and lucrative career as Carnation Instant Breakfast. The Space Food Stick also began life as a military washout. What the Air Force called “rod-shaped food for high-altitude feeding” was originally intended as food that could be poked through the port of a pressure suit helmet. “We couldn’t get them stiff enough,” O’Hara told me. So Pillsbury took back its rods and went commercial with them. Bourland says they occasionally went up with the astronauts simply as an onboard snack—sometimes under the name Nutrient-Defined Food Sticks and other times as Caramel Sticks, fooling no one.

Even the companies who made food sticks and breakfast drinks didn’t expect the American family to eat nothing else. I have reason to believe that a cabal of extreme nutritionists was influencing thought at NASA. These were men who referred to coffee as a “two-carbon compound.” Who wrote entire textbook chapters on “topping strategies.” Here is MIT nutritionist Nevin S. Scrimshaw defending the liquid formula diet at the Conference on Nutrition in Space and Related Waste Problems in 1964: “Persons with other worthwhile and challenging things to fill their time do not necessarily require bits to hold in their mouth and chew or a variety of foods in order to be productive and to have high morale.” Scrimshaw boasted of having fed his MIT subjects liquid formula dinners for two months with no complaint. The Gemini astronauts narrowly escaped a fate worse than cubes. “We are hoping, in the Gemini program,” said NASA man Edward Michel at that same conference, “to go to some type of formula diet…. We will use it during pre-flight, during the flight, and for a 2-week period post-flight.”

Scrimshaw was wrong. People do “necessarily require bits to hold in their mouth and chew.” Put them on liquid diets and they crave solid food. I spent just one morning on the Mercury-era tube diet, and I did. The astronauts no longer eat tubed food, but military pilots do, when they’re in the middle of a mission and can’t stop to unwrap a sandwich. Vicki Loveridge, a helpful and congenial food technologist with the Combat Feeding Directorate at U.S. Army Natick, said the formulation and technology have changed little since the Mercury era. Loveridge invited me to Natick. (“Dan Nattress will be making Apple Pie in the tubes on the morning of the 21st.”) I couldn’t go, but she was kind enough to send me a sampler box. They look like my stepdaughter Lily’s tubes of oil paint.

Tube eating is a uniquely disquieting experience. It requires bypassing the two quality control systems available to the human organism: looking and sniffing. Bourland told me the astronauts hated the tubes for precisely this reason: “Because they could not see or smell what they were eating.” Also unnerving is the texture, or “mouthfeel,” to use a food technology coinage. When a label says Sloppy Joe, you expect some Joe. The Natick version has no discernible ground-beef qualities. It’s puréed. All tubed food is, because, as Charles Bourland put it, “the texture is limited to the orifice of the tube.” The very first space food was essentially baby food. But even babies get to eat off spoons. Mercury astronauts had to suckle theirs from an aluminum orifice. It wasn’t heroic at all. Or, as it turned out, necessary. A spoon and an open container will work fine in zero gravity as long as the food possesses, to quote the adorable May O’Hara, “stick-to-it-ive-ness or whatever.” If it’s thick and moist enough, surface tension will keep it from drifting off.

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