It’s not an entirely novel question: “How do astronauts do their business in space?” But that doesn’t mean the answer is any less fascinating.

We’ve already seen the lengths to which astronauts have to go to do things like wash their hands on the International Space Station, but using the restroom? Well, that’s a completely different ballgame and, as the host of SciShow Space on YouTube explained, training for how to use a toilet in zero gravity starts on Earth.

The new $19 million toilets used in space, unlike the porcelain thrones used on Earth, which retail, on average, for a few hundred dollars, are only about 10 centimeters in diameter.

The toilet system on the International Space Station. (Image source: NASA)

The toilet system on the International Space Station. (Image source: NASA)

“You know, because you want to make sure that it all stays where you put it,” the host said.

But that’s not the only uncomfortable tidbit of information. In order to learn how they’re going to have to use the toilet in space, SciShow Space pointed out that NASA put a camera inside the training toilet so astronauts can see in real-time “how best to position themselves and avoid any unfortunate mishaps.”

When actually in space, astronauts tie themselves to the toilet so they can go without having to hold themselves down. The waste is sucked from the toilet with a vacuum into a receptacle. Urine specifically, for both men and women, requires the use of a urinal funnel.

While solid waste is stored until a spacecraft is headed back to Earth where it will be disposed, urine is purified into water that is actually used for drinking or bathing, SciShow Space said.

Watch SciShow Space’s full video for more about how astronauts use the restroom in space and what’s done with the after products:

While collection of waste in space today is highly advanced, it wasn’t without its hiccups in NASA’s earlier days. According to an article on Space.com last year, a mission failure in the 1960s was actually caused by faulty urine collection that ended up leaking and led other systems to break. Going number two was also far less high-tech back then than it is now.

(H/T: Daily Mail)

Front page image via Shutterstock.