One of the most unglamorous aspects about living in space is one of the most asked about by civilians: how do people use a space toilet in zero gravity? As the response to many jokes go, “very carefully.”
Human Waste No Joke in Space
Back in 1961, NASA was forced to deal with the subject of a space toilet when what was supposed to be a 15-minute flight turned into a five-hour ordeal for astronaut Alan Shepard. He was locked into the Freedom 7 space capsule through delay after delay and he needed to pee. Officials finally had to allow him to pee into his spacesuit.
When it came time for Gordon Cooper to travel for 34 hours orbiting the earth in 1963, NASA thought they had the urine problem solved by having him wear a urine collection bag as a space toilet. Toward the end of his mission, systems in the space capsule started failing mysteriously, forcing Cooper to take manual control of entering the Earth’s atmosphere, a very dangerous undertaking. NASA later determined that the system failures were due to a leak in his urine collection bag, allowing minuscule droplets of liquid to get into the electronics.
The Mir space station built by the Soviet Union thought they had the space toilet problem solved by simply allowing urine to pass out into space. By the time the space station finished its travel through space and was retired in 2001, they realized that the solar panels had lost 40% effectiveness, partly due to frozen urine speeding around.
Toileting on the ISS
Today, Italian astronaut Samantha Cristoforetti gave the public a tour of the space toilet facility on the International Space Station (ISS) and it’s considerably more advanced than a urine collection bag. To compensate for the lack of gravity, the space toilet system uses a fan to create a vacuum that draws waste away from the body. Urine is collected through a tube, filtered, treated and recycled for drinking. The system constantly tests for purity and it provides most of the vital drinking water on the station.
Solid waste is collected, very carefully, in plastic bags that are placed into a collection bin. The bin is then ejected by visiting spacecraft upon re-entry into Earth’s orbit and it burns up along with other space trash collected from the space station. Researchers continue to try to find ways to recycle the solid waste and make it into something useful.
Cristoforetti showed that the toilet doesn’t look anything like what we have on earth; in space, there is no need to sit on a space toilet. However, astronauts have to travel through a kind of potty training to make sure they get their waste into the 4-inch opening on the collection device and into the plastic bag. She explains that the crew uses proper bathroom etiquette and each member politely places a new bag in the device after each use.