You’re an astronaut, going into your fifth hour on a spacewalk to perform some maintenance on the
International Space Station, 125 miles above Earth. And then - reality hits:
you have to pee, and you have to pee now. Where do you go? What do you do?
How do astronauts pee in space?
An official NASA report from the 1970s called bathroom habits, quote, “a bothersome
aspect...from the beginning.” Contemporary astronauts claim bodily functions are the most
frequently-asked queries about space travel - from children and adults! As an astronaut on the ISS,
it’s been a long journey to get where you are today - not just for you, but for your bladder.
The first NASA astronaut to have to consider the question was Alan Shepard,
the first American in space, on May 5, 1961.
While NASA submitted designs to Congress that included a designated container for “liquid waste”
in their one-man space capsule, the reality was much different - after all, they figured,
Shepard was only scheduled for a 15-minute suborbital experience, nothing too crazy.
Shepard entered his capsule hours before the expected launch time, remaining on his back as a
series of weather and technical issues continued to push the launch time by another two hours!
Eventually, Shepard told the ground crew he had to use the bathroom. Realizing it would further delay
the launch if they let him out, the ground crew declined his request. So he urinated right there,
the liquid splashing up his back in the process - they even had to turn off sensors in his suit to
make sure they didn’t short circuit. Shepard later said the cotton undergarment he wore
soaked most of it up, so he was good and dry by the time the Freedom 7 finally launched.
By the way, the first human in space, Russian cosmonaut Yuri Gagarin,
encountered a similar problem earlier that year, April 12. His trip lasted 108 minutes
from launch to landing, and he didn’t have any facilities aboard his capsule, either. How did
the Soviet space program solve his bathroom needs? Simple - on the way to the launch site,
Gagarin asked the bus driver to pull over. He then got out and peed on the right back tire, starting
a cosmonaut tradition that lasted almost 60 years. He made his flight without any reported incidents.
Meanwhile, back at NASA, the issue with Shepard demonstrated a problem for the American space
program: if they wanted to continue putting people in space, they needed to come up with
a waste disposal plan. And that meant some creative solutions to the problem.
July 1961 - Gus Grissom is the next American to fly into space.
Popular legend had nurse Dee O’Hara solving the bathroom issue by buying a condom and a girdle,
and fixing them together to give the astronaut needed relief.
In reality, Grissom was given two pairs of rubber pants, trapping whatever urine he expelled,
and making for easy cleanup. A solution that NASA knew was more temporary than permanent.
Even before Grissom took off, James McBarron was hard at work on an official
Urine Collection Device - or UCD - to make nature’s call more suitable for outer space.
McBarron went practical, basing his design on the condom - his research consisted of
buying several brands and trying them on himself...though given the final version,
we don’t know that that thoroughness was completely necessary - fun for him, though! The
result became the official Urine Transfer System, or UTS, for the remaining Mercury missions.
Open-ended on both sides, the “roll-on-cuff” or “sheath” came in three sizes - small, medium,
and large - and was worn by astronauts on one end, with the other end wrapped around the opening of
a bag. A nylon strap secured the cuff to the bag, and the astronaut’s undergarment held
the bag in place. A spring-loaded metal clamp kept the urine from leaking, so it could be disposed
of later. Apollo 16’s Charlie Duke claimed it was then attached to a sort-of jockstrap
astronauts wore about their waist, with one hole in front to roll on the sheath, and an open back
for the so-called Fecal Containment Device, which Duke compared to, quote, “a ladies’ girdle.”
Of course, that brought a whole different aspect to things - the FCD may have been a girdle, but
what it held in place was basically a plastic bag, with a little finger-pocket to make sure nothing
got stuck to the body. After doing their business, astronauts would then have to seal the bag,
detach it, and knead it in order to mix whatever they evacuated with the liquid bactericide inside,
stabilizing the fecal matter so it could be expunged - or, in some cases,
brought back to Earth for observation and research. The entire system was messy and
imperfect, but it would have to do ‘til NASA could come up with something else - in the
meantime, diets were adjusted - food became limited, low residue meals,
and some drugs were even used to slow down the whole digestion-to-evacuation process.
John Glenn was the first US astronaut to experience this new contraption,
and he used it during his nearly five-hour orbit around the globe. During that trip,
he reported no abnormalities in his functions - like astronauts today,
Glenn said he only went when he finally felt the need, no different from the feeling on Earth.
However, when he finally vacated his bladder just before reentry, he expelled 27 ounces of
liquid - 7 ounces more than the average human bladder holds at maximum capacity! Why didn’t
he feel the need before? The weightlessness of even microgravity affects bodily fluids the same
as it does everything else: everything travels up. This explains why astronauts tend to look puffier
in space compared to when they’re grounded - the blood flow has traveled up - and why,
like Glenn, by the time they feel the need to answer nature’s call, it’s already too late.
Still, zero-g bladder functions weren’t reflective of the UTS’s effectiveness,
and McBarron’s design became the standard for manned spaceflights, all the way through to the
Apollo missions. Even Apollo 11’s Buzz Aldrin has talked about using this system - proudly
proclaiming himself not just the second man on the moon, but the first man to pee on the moon.
But now a new, unexpected, unscientific problem arose: size. As we said, each “sheath,” as the
condoms were now called, came in various, color-coordinated sizes - small, medium,
and large - a designation which some astronauts got very sensitive about. According to Apollo
9’s Russell Schweickart, “if you get too small a size it effectively pinches off the flow and
you just...can’t go; and if on the other hand you’ve got an ego problem and you decide on a
large when you should have a medium...you end up with half of the urine outside the bag on you.”
Reportedly, that happened enough that the size designations were then changed to “large,”
“gigantic,” and “humongous.” Because scientific progress is equal parts ego and practicality.
With more men spending longer hours in larger spacecraft,
new systems of waste disposal were developed for the Apollo missions. A designated waste
management system included a hose connected to a line within the walls of the spacecraft
that could collect urine and dump it into space. The hose had two lines inside - one for the UTS,
and one for the Urine Receptacle Assembly, URA, a valve that allowed astronauts to use
the bathroom on the shuttle, with a honeycombed system that kept the urine stable through zero-g.
The dumping process had its limitations, however - it had to be timed just right so that urine didn’t
escape into the ship itself, or timed so that the urine cloud that formed outside wouldn’t obstruct
the view at a time when scientific observations of activity outside the craft were scheduled.
One scenario where dumping the urine wasn’t an option came up in April 1970, during the famous
Apollo 13 flight. You probably remember the movie: an explosion in the service module resulted in the
loss of two oxygen tanks and damaged life support systems. The astronauts were forced to power down
the command module, saving its resources for reentry; cram together in the still-attached
lunar module; loop around the moon; and return to Earth - a trip that lasted four days. Even
with them rationing water to 7 ounces per person a day, urination would still be a necessity - but
not only could a pee dump reduce what little electrical resources they had left,
it could also have affected their trajectory. NASA asked them not to dump any more urine, so they had
to start peeing in bags stored around the limited space, adding another unpleasant element to an
already not-ideal situation. Fred Haise solved the problem his own way: he kept his UTS on,
so if he had to pee, he could do so in his suit; otherwise, the three astronauts agreed to hold
off urinating as much as possible. Between the lack of water, holding his bladder for too long,
and continuing to soak in what he did expel, Haise wound up developing a kidney infection and a UTI.
The next couple of decades saw the advent of space shuttles, space stations,
months-long missions - and the introduction of female astronauts. Bathroom habits had to change.
The original design for the space shuttle toilet included straps to keep the feet in place,
handles to keep the astronauts from flying off, a four-inch opening that required perfect aim for
other business - and a hose attachment for going number one. The toilet and hose were pressurized
and included vacuum suction, powered on by switches at the base and by the arm,
the better to, uh, “grab” whatever was coming out.
To ensure as little urine as possible floated away, a funnel was attached to the hose - for men,
a single, simple design, one that needed to be held a little away from the body to avoid pooling.
For women, three separate designs, all of which could be held flush against the skin. The whole
execution was precarious enough to require special training on Earth - including a camera
to make sure you positioned yourself on the toilet seat just right - and many female astronauts have
discussed sharing tips with each other on the best way to arrange things to allow for...dual ops.
With some adjustments, it’s not too dissimilar from the smaller, sleeker, modern toilet on
today’s International Space Station. The Universal Waste Management System still has the straps
and handles, still uses the hose with funnel attachment, though that’s in a more convenient
place than it was before. Per female astronauts’ request, the new design allows for both the hose
and the seat to be used simultaneously, if necessary, with the pee funnel’s design
adjusted with women’s needs specifically in mind. Air flow is now automatic when the seat
is lifted or the hose detached, sucking the pee away. That pee is then treated with acids in a
filtration system that recycles the urine through the station’s water system, where it can be reused
as drinking water. Or as astronaut Jessica Meir put it, “Today’s coffee is tomorrow’s coffee.”
The evolution of space tourism has also led to some original re-designs of the space toilet.
The mechanics of the one for SpaceX’s Crew Dragon are still shrouded in secrecy as of August 2021,
but we do know that the bathroom will be located in the nose of the space capsule.
That section is usually reserved for docking, but the Inspiration4 won’t be connecting to the ISS.
Instead, the nose will be turned into a 360-degree domed window, a cupola,
offering magnificent views of the Earth...that can be enjoyed while astronauts sit down and
attend to their business. A privacy curtain separates the area from the rest of the ship.
All that toilet talk is fine for the space vehicles - but back to you and your spacewalk.
Because your spacesuit is pressurized, with its own oxygen and water supplies,
you’ve had to don it several hours in advance to get your body used to
it - that way you don’t get the bends. After that, your work during the spacewalk can take
anywhere between five and nine hours. A long time to go without peeing. So what do you do?
This is where the introduction of women into the space program led to some necessary - and
convenient - innovations. The old condom-based UTS was obviously unusable for female astronauts.
In its place came the Disposable Absorption Containment Trunk, or DACT, and then later,
the Maximum Absorbent Garment, or MAG. Different names, same overall design and principle:
designed to be pulled up onto the body like a pair of shorts, they resemble adult diapers...and they
pretty much are. Except they are more absorbent, thanks to the sodium polyacrylate powder woven
into the fabric, which can absorb up to two quarts of liquid - urine, menstrual blood,
excrement, etc. - pulling it away from the skin to prevent irritation. The convenience of the
MAGs led to male astronauts also adopting them. Every astronaut receives three:
one for the initial launch, one for reentry, and one for extravehicular activities,
which usually include...yup, spacewalks. Go ahead - let loose.
Now go watch what really happens to your body if you die in space,
or click this other video instead!