 Having to use the washroom is one of the most basic human needs. And it's not something we think about too often, because public and private washrooms are basically anywhere you need them any time. But the same can't be said in space. In space, going to the washroom is a much more complicated affair, especially when it comes to defecation. I'm Amy Shira Tidal and this is a Vintage Space video. During the Mercury program, when missions lasted less than 35 hours, NASA took preventative measures against its astronauts defecating. The agency fed the astronauts low-residue diets, diets consisting of food that left very little waste after the body had absorbed all necessary nutrients. Things got more complicated, however, during Germany and Apollo missions when flights lasted as long as two weeks. It wasn't enough for astronauts to be on low-residue diets. They needed some kind of fecal containment system. And the one NASA developed for Apollo and Germany flights was rudimentary at best. A long plastic bag with a sticky surface around the opening that astronauts could adhere to their bodies and use as a makeshift toilet. The bags were then stored for the duration of the flight, since there was no way of jettisoning solid waste from the spacecraft. But things got better when NASA unveiled the first space toilet on the space shuttle. However, it wasn't a perfect system. The first version of the space toilet from NASA was a complicated system. It used airflow rather than gravity to separate waste from the user, as well as to separate solid from liquid waste. Liquid waste was then jettisoned out the side of the spacecraft, but solid waste was exposed to the vacuum of space and vacuum dried and then stored for the duration of the flight. The whole system used a series of valves, pumps, and motorized spinning pieces. And it wasn't perfect. Vacuum drying fecal matter tended to create fecal dust. And if this dust were to reconstitute in a moist environment, say, an astronaut's throat or nasal passage, it would be a serious problem. Eventually, a better system was unveiled during the STS-41D flight in 1984, a much simpler toilet that didn't have as many moving parts. Currently, on the International Space Station, astronauts use a toilet that recycles waste water, and jettisons fecal matter with the garbage and it's left to burn up in the atmosphere. For more on a brief history of fecal containment systems and some more details on old fecal containment systems, check out the articles linked below.