Nature’s call waits for no one  – zero gravity, or not. Thanks to what looks like a vacuum hose with a funnel attachment, and European Space Agency astronaut Samantha Cristoforetti, we are now well-versed in the art of the “space go.”

Life aboard the International Space Station (ISS) comes with a myriad of challenges, but keeping your space-waste from floating away is one you don’t always think about. The station’s lavish lavatory is complete with a urine-sucking hose, and a toilet seat fit for Tyrion Lannister. Cristoforetti explains the small surface area isn’t a problem, since you don’t really sit in zero gravity. The solution? Aim well.

Of course, solid waste is deposited into a storage container for disposal, but the water-rich urine? That’s a commodity worth saving. “Yesterday’s coffee becomes today’s coffee,” explains ISS resident Don Pettit.  The station’s water recovery system doesn’t just filter and distill astro-pee, everything from shower water, to the sweat an astronaut produces is collected, recycled and reused by the crew, thanks to what, at its core, is a system of sideways beer kegs.

On Earth, distilling is a simple process: water is boiled, steam is cooled, and presto-change-o, you’re left with pure water sans-impurities. But without gravity, the contaminants in water won’t separate from steam, no matter how much heat you add to the equation. The solution is actually pretty simple: spin the hell out of the kegs. High velocity spinning produces an artificial gravity field which effects the drum’s contents. The contaminants in the grey water press against the sides of the drum while the steam gathers in the middle and is pumped to a filter. The process collects 6,000 pounds (about 720 gallons, or 2,725 liters) of potable water per year, allowing the station to host up to six astronauts at a time, rather than three. One man’s gross is another man’s incredible feat of engineering.

—

IMAGES: European Space Agency