To Boldly Go: The Science Behind Pooping in Space

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iStock

What Mike Mullane remembers most clearly about having his first bowel movement in space is the blast of cold air greeting his exposed rectum. Over the course of three week-long NASA shuttle missions in the 1980s—two for Discovery, one for Atlantis—Mullane was forced to answer nature's call six or seven times in zero gravity. Each time, he would have to strip naked, close a flimsy curtain around a titanium commode, position his buttocks to form a perfect seal around a 4-inch opening, and then follow a checklist posted nearby to make sure no fecal particles escaped into the deck—all while his sphincter insisted on clamping shut to escape the freezing temperatures.

"It was a complex operation," Mullane tells Mental Floss. "On Earth, I'm fast. My wife is amazed I can be in and out of the bathroom in one minute for a number two. On the shuttle, it would take 30."

While the industrial toilet was a far cry from five-star hotel room seat warmers and bidets, it also improved by magnitudes the ordeal of emptying one's intestines in zero gravity. Prior to 1972, the men of the Gemini and Apollo missions braved poop bags that they would stick to their rear ends, then manually knead the contents with an antibacterial solution so the gases wouldn't detonate the collection; more than one crew has been terrorized by rogue turds hovering in the air.

Coming up with a practical way of replicating the earthbound poop experience took many years, many engineers, and a whole lot of ingenuity. While few explorers like to discuss it, taking a space dump is its own kind of heroism.

Consider one early—and discarded—solution for waste collection in space, which someone dubbed the "sh*t mitt." Donald Rethke likens it to "those long rubber gloves veterinarians use for insemination." The idea, he tells Mental Floss, was that the astronaut could poop in their own hand and then turn the glove inside-out, creating instant containment of the feces.

Now 80, Rethke is a retired engineer from Hamilton-Standard, a NASA subcontractor working through Northrop Grumman that spent decades refining or pioneering life-support systems for space explorers. Rethke, who embraces his industry nickname of "Doctor Flush," says that handling poop simply wasn't much of a concern due to the brief trips taken by pioneering astronauts: They could just go before they left. But as missions grew longer, it became necessary to address personal waste—urine and bowel movements—without dealing with the discomfort of diapers.

A NASA training commode
A training toilet with a camera positioned inside so astronauts can learn how to best angle their buttocks.
National Geographic, YouTube

For the 1965–66 Gemini excursions, which were planned to prove humans could survive for several days or weeks in space, astronauts were told to use a condom-like sheath that would direct urine into a bag. For feces, they were to use a pouch with a 1.5-inch opening and an adhesive strip around the edge to help prevent fecal matter from escaping. A fellow crew member would be told to stand by and watch to make sure no waste escaped into the capsule.

"It kind of looked like an upside-down top hat," Mullane says. Though they pre-dated his missions, they were on board his shuttles in case of equipment failure. "We never had to use them, thank God."

But the occupants of Gemini and Apollo did, and most found it unpleasant for reasons unrelated to crapping in a bag. When gravity is lacking, surface tension becomes a dominant force. So urine and feces that would separate from the body on Earth thanks to gravity tend to cling to the skin's surface in space.

"If you stick your finger into a glass of water and lift it up, water flows off," Mullane explains. "But in weightlessness, the attraction of the molecules of the fluid will pull it into a ball. If you leave fluid alone, it will form a perfect sphere. Touch it, and will stick to you."

The same goes for poop. The bags had tiny finger covers built in so users could flick and scrape errant flecks away from their cheeks. Then they'd mix in a chemical to kill the bacteria so the gases wouldn't expand in the sealed bag and create an explosive biohazard.

"Well, it's in a small, like a ketchup, a little plastic container like you find ketchup in in restaurants, in a cafeteria or something, it's like that," Apollo astronaut Russell Sweickhart told a reporter in 1977. "You tear the slit across the top, being careful not to squeeze it so the stuff comes out, and then you drop that into the fecal container, and then seal the fecal container. Then you squeeze it through the, you know, externally, you know, which forces it out of the container, and then you mix it by massaging the fecal bag. It's really fun when it's still warm."

If everything went well, it was merely disgusting. If it didn't, as the following transcript excerpt from the 1969 Apollo 10 mission demonstrates, it could be highly disruptive:

Tom Stafford: Give me a napkin quick. There's a turd floating through the air.

John Young: I didn't do it. It ain't one of mine.

Gene Cernan: I don't think it's one of mine.

Stafford: Mine was a little more sticky than that. Throw that away.

Young: God Almighty.

"When the Apollo astronauts came back," Rethke says, "they wanted sit-down toilets."

A look at the ISS bathroom
The "orbital outhouse" inside the International Space Station.
NASA

While modesty may not have been an achievable goal, astronauts needed some semblance of routine. (Some shuttles were equipped with kitchen tables, even though nothing in zero gravity could be perched on one.) But the comforts of a domestic commode had little application in space. No water could be used: It would run everywhere. And unlike gravity-assisted toilets, a shuttle john would have to address the surface tension issue that enticed poop to come out in curls instead of straight down, mashing itself against the skin.

The solution, according to Rethke, was gentle suction. "Or, as I like to call it, air entrainment," he says. In its simplest form, it's getting the poop Hoovered away from your bottom using air flow as a substitute for gravity.

Rethke says the idea was already on the table courtesy of General Electric (GE) when Hamilton-Standard began working on a zero gravity toilet, and that his job was one of refinement that lasted through the 1980s and 1990s. "The concept of separating solids from the body was already in the bag, no pun intended. It was just the best way. Most of my effort was how to do that economically."

NASA had previously toyed with a variety of designs, including one 1971 model that was mounted vertically on a wall to conserve space. Another took the feces and pulped it, a model not unlike evacuating into a blender. This, engineers realized, created the potential for fecal "dust," or powdered particles of poop, that could contaminate the cabin of spacecraft. By using air entrainment, hardly anything could escape the bowl—and if it did, it wouldn't be atomized to the point of being a biological hazard. Instead, a fan and vacuum system was used to encourage the waste to settle at the bottom of the waste tube.

Air entrainment made one frustrating demand of its users: proper anal positioning. With a 4-inch opening compared to a conventional toilet's 18 inches, astronauts had to align themselves up perfectly in order to avoid any escaping feces. To train astronauts heading for space, NASA set up a commode with a camera mounted inside. (You were not expected to make a deposit.) Users could gauge their perch based on freckles or other skin marks in relation to the seat. Properly docked, they could poop on target, but it took practice.

"It's hard to know where your a-hole is when the hole is that narrow," Mullane says.

Minor complaints aside, NASA's work was ready in time for the 1973 debut of Skylab, the first space station, and the 1981 launch of Columbia, the first shuttle to reach space. After realizing the pulverizing model wasn't going to work due to the fecal dust issue and other malfunctions that led to problems on 10 of the shuttle's first 11 voyages, a redesigned system less prone to clogging was introduced in the mid-1980s.

Urinating, according to Mullane, was never any big deal. Men and women use a form-fitting cup and gentle suction to empty their bladder. "Pretty simple," he says. "But solid waste, that was kind of like going in a camper toilet."

On the Atlantis and Discovery, the space commode had foot rests and thigh straps so astronauts could remain secure to the seat while doing their business. They'd typically opt to strip naked in the event any soiling occurred. To the right was a hand lever; pushed forward, it slid open the tube underneath their buttocks. "You never wanted to open that before sitting on it," Mullane says. Doing so could release the previous user's residual fecal matter into the air.

Once Mullane was strapped in, he would open the tube cover and feel the rush of cold air hit his rear. The air moved 360 degrees while a fan underneath—loud enough to mask sounds of elimination—pulled waste away from the body and into a container that would store the matter until the shuttle returned. Toilet paper would go in a separate bag. By the time Mullane got dressed, cleaned the toilet's edges, and exited, 30 minutes had passed.

Surprisingly, the intimate size of the shuttle didn't contribute to any fragrant evidence. "They did a really good job of filtration," Mullane says. "You never smelled anything."

Rethke improved on this in the early 1990s by compacting the discarded feces at the bottom, reducing the need for storage space. (To make sure it would stay sealed, Rethke once kept a feces-filled container in his office for a year.)

Small tweaks aside, the space toilet doesn't follow the update schedule of, say, an iPhone. What Rethke redesigned and what Mullane used is, by and large, what's still in use on the International Space Station (ISS) today. But instead of bringing waste back, it's discarded so it burns up in the atmosphere.

Future movements may prove more difficult to handle. With the advent of long-duration travel, possibly to Mars, on the horizon, space exploration will have to deal with the issue of waste management when there's virtually no chance of Earthbound assistance.

"When toilets fail [on Earth], it's a real pain," Mullane says. "Just imagine that on Mars. I have no idea how they're going to do that."

Someone might. In early 2017, the HeroX platform crowned a winner in its Space Poop Challenge, which crowdsourced ways to handle waste in space when an explorer is in a spacesuit and away from a fixed toilet for long periods. The winning idea—a suit hatch that can be used to insert inflatable bedpans and diapers—earned inventor Thatcher Cardon a $15,000 prize. If it works, it'll assist in an integral part of exploring beyond our atmospheric borders. In space, everyone needs to go.

Additional Sources: Riding Rockets: The Outrageous Tales of a Space Shuttle Astronaut

15 Convenient Products That Are Perfect for Summer

First Colonial/Lunatec/Safe Touch
First Colonial/Lunatec/Safe Touch

The Fourth of July is the epitome of summer—and after several months spent indoors, you need some outdoor fun more than anything. Check out these 15 summer must-haves while they’re on sale and save an extra 15 percent when you spend $50 or more with the code JULYFOURTH15.

1. CARSULE Pop-Up Cabin for Your Car; $300 (20 percent off)

Carsule tent from Mogics.
Mogics

This tent connects to your hatchback car like a tailgate mobile living room. The installation takes just a few minutes and the entire thing stands 6.5 feet tall so you can enjoy the outdoors from the comfort of your car.

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2. Mosquito Killer Lamp; $30 (25 percent off)

Mosquito-killing lamp.
Kinkoo

If you just so happen to be one of those unlucky souls who attracts a suspicious amount of mosquitos the second you step outside, you need this repellent lamp to help keep your arms and legs bite-free. It uses a non-toxic combination of LED lights, air turbulence, and other methods to keep the pests at bay.

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3. Super Shield Mosquito Repellent Electronic Watch Band; $17 (57 percent off)

Mosquito repeller watch.
Safe Touch

While a lamp is a great non-toxic solution for keeping bugs at bay, active individuals need a bug repellent that can keep up with their lifestyle. This wrist wearable keeps you safe from mosquitoes anywhere by using ultrasonic sounds to drive them away.

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4. ZeroDark 3-Piece Tactical Set: Flashlight, Lantern, and Headlamp; $20 (66 percent off)

Aduro flashlight set.
Audro

If you want your summer to be lit, this set will do the trick. All puns aside, this trio of LED brightness is perfect for camping fun and backyard parties, or it can be stored in the car for emergencies.

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5. Outdoor Collapsible Cooler and Camp Table Set; $64 (27 percent off)

First Colonial cooler.
First Colonial

Cookouts are easy with this cooler and table set that chills your drink until you're ready to pop it into one of the four convenient cupholders. Bring this set camping or out by the pool for convenience anywhere.

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6. Trident: Underwater Scooter; $550 (21 percent off)

Trident underwater scooter.
Geneinno

If you’ve ever dreamed of better mobility while exploring the water, you’re not alone. The Trident underwater scooter, which raised over $82,000 on Indiegogo, can propel you through the water at up to nearly 6 feet per second, which isn't that far off from how fast Michael Phelps swam in his prime. The battery on it will last 45 minutes, allowing you to traverse with ease.

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7. Go Portable Solar Oven; $119 (14 percent off)

GoSun solar grill.
GoSun

Bake, roast, steam, or broil anywhere you bring this portable oven. Measuring in at just over a foot long and weighing only two pounds, the oven will work in most daytime weather conditions and can hold around 13 ounces of food.

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8. 3-in-1 Waterproof Bug Zapper Lantern; $25 (50 percent off)

3P Experts bug zapper.
3P Experts

Mosquitoes tend to be a big problem at night, partly because it's hard to swat in the dark. This lantern will light the area and zap mosquitos from nipping at you in the process.

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9. Urban E-Skateboard: Basic Version (Orange); $120 (73 percent off)

Urban Rover E-Skateboard
Urban Rover

This e-skateboard is perfect for getting around during the summer. You'll catch a breeze while you’re cruising on the battery-powered platform and won’t break a sweat when you pop the compact board in your bag.

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10. H2 Headlamp: Waterproof, Rechargeable LED Wide 180° Angle Headlight; $37 (26 percent off)

Headlamp from One80Light
One80Light

Camping, car troubles, and sports all pose a problem at night. This LED headlight will light up your surroundings across a 180-degree radius for prime visibility, meaning your outdoor activities won't have to stop when the sun sets.

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11. Whirlwind Cool Bladeless Mini Fan; $22 (63 percent off)

Bladeless fan
Whirlwind

This portable fan comes in a powerful handheld size so you can keep cool while on the move. Unlike other portable fans, this one has a sleek, bladeless design and features three different speeds.

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12. Bladeless Personal Fan; $22 (63 percent off)

Bladeless fan
3P Tech

This bladeless fan won't just keep you cool while you work on your laptop—it also has a built-in rechargable battery that you can use to charge your phone.

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13. MOGICS Coconut: Portable Waterproof Light; $37 (24 percent off)

Mogics portable lamp.
Mogics

This portable light is designed to adapt to your lighting preference. It self-inflates in a few seconds and can bounce, get wet, and set the mood.

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14. Lunatec 1L Hydration Spray Water Bottle; $25 (21 percent off)

Lunatec spray water bottle.
Lunatec

A water bottle can do more than hydrate you. This one has a spray nozzle that can create shower, stream, and mist patterns for doing dishes while camping, sharing a sip without sharing germs, and washing off those muddy shoes after a long hike.

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15. Sport Force Hydration Backpack; $25 (68 percent off)

Hydration backpack.
It's All Goods

Hiking enthusiasts know how important it is to stay hydrated, but carrying around awkward jugs of water is a hassle. This unique hydration backpack can be filled with two liters of water and features a convenient drinking nozzle that extends to the user's mouth. Now, you can replenish those fluids without breaking stride.

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NASA Names Washington, D.C., Headquarters After ‘Hidden Figure’ Mary Jackson

Mary W. Jackson at NASA in 1980.
Mary W. Jackson at NASA in 1980.
Adam Cuerden, NASA Langley Research Center, Wikimedia Commons // Public Domain

In the past, NASA’s headquarters building in Washington, D.C., was simply known as “NASA Headquarters” or “Two Independence Square” (the name of that particular piece of real estate). This week, the agency officially named it the “Mary W. Jackson NASA Headquarters,” after NASA’s first Black female engineer.

Jackson worked as a math teacher and U.S. Army Secretary before NASA—called the National Advisory Committee for Aeronautics at the time—recruited her as a research mathematician for its segregated West Area Computing Unit in 1951. After completing a training program in 1958 (which she needed special permission to attend, since it took place at a whites-only high school), she was promoted to engineer.

In the following decades, Jackson studied wind tunnels and air behavior around aircraft, and she was also instrumental in helping the U.S. pull forward in the Space Race of the 1960s. But Jackson’s legacy goes beyond her own engineering efforts: Between 1979 and 1985, she participated in the Federal Women’s Program at NASA’s Langley Research Center, where she advocated for the hiring and promotion of more female scientists.

mary jackson with young female scientists in 1983
Jackson with a group of young scientists and mathematicians in 1983.

“Mary W. Jackson was part of a group of very important women who helped NASA succeed in getting American astronauts into space,” NASA administrator Jim Bridenstine said in a press release. “Mary never accepted the status quo; she helped break barriers and open opportunities for African Americans and women in the field of engineering and technology.”

Jackson died in 2005, and her story was largely unknown until the release of Margot Lee Shetterly’s 2016 book Hidden Figures and subsequent film of the same name, which chronicled the contributions of Jackson and her colleagues Katherine Johnson, Dorothy Vaughan, and Christine Darden. In 2019, Congress passed a bipartisan bill to rename the part of E Street SW where NASA’s headquarters is located to Hidden Figures Way, and the women were also awarded Congressional Gold Medals.

NASA headquarters
The Mary W. Jackson NASA Headquarters in Washington, D.C.

“We are honored that NASA continues to celebrate the legacy of our mother and grandmother Mary W. Jackson,” Jackson’s daughter Carolyn Lewis said in the press release. “She was a scientist, humanitarian, wife, mother, and trailblazer who paved the way for thousands of others to succeed, not only at NASA, but throughout this nation.”