Astronauts get to have experiences that only a handful of people on Earth will ever have, but there are some less-than-glamorous moments that come with the job, too.
Astronaut Scott Kelly has almost spent a full year living and working on the International Space Station (ISS), and he recently hosted a Reddit AMA where he revealed one of those less-than-glamorous moments.
"What's the creepiest thing you've encountered on the job?" Reddit user lula2488 asked Kelly.
There are plenty of ways Kelly could have answered this question, but he picked an especially horrifying one.
"Generally it has to do with the toilet," Kelly said. "Recently I had to clean up a gallon-sized ball of urine mixed with acid. The acid is added to the urine so the urine doesn't damage the machinery that moves it through the system. It keeps it from clogging up the system."
Kelly didn't elaborate on what malfunction caused the mess, but this isn't the first time we've heard astronauts talk about the horrors of space toilets, so it's not hard to imagine.
When astronauts pee, the urine gets sucked into this yellow nozzle and down a tube:
"The number one stuff can get really all over the place if you don't aim correctly," astronaut Sunita Williams warned in a video tour of the ISS once.
That's because in space, liquid (including urine) tends to clump into spheres, and microgravity sends them floating through the air.
Yikes.
But that's not the end of the story. Astronaut urine gets run through a filter on the ISS and converted back into drinking water.
We have to imagine most astronauts don't spend a lot of time thinking about where the water comes from when they're brewing a cup of coffee in the morning.
