NASA astronaut Suni Williams explains what it’s like to poop in space. NASA

What could be more daunting than strapping into a rocket for a trip to space? Pooping once you get there. It’s top of mind for NASA astronaut Jack Fischer, who is headed up to the International Space Station April 20. In a NASA interview, Fischer told the space agency that “using the toilet” will be his greatest challenge.

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“It’s all about suction, it’s really difficult, and I’m a bit terrified,” Fischer said. “Unlike most things, you just can’t train for that on the ground — so I approach my space-toilet activities with respect, preparation, and a healthy dose of sheer terror.”

He’ll have to get used to the toilet of terror because he’ll be in orbit around Earth for four months.

During that time, Fischer will be doing research: “There are almost 300 experiments planned for our mission, ranging from plant growth to bone growth, and everything in between.” He may participate in a spacewalk as well.

The American is launching on a Soyuz spacecraft from Roscosmos, Russia’s space agency, along with their own astronaut, Fyodor Yurchikhin.

So what is it like to pee and poop in space? Many have wondered, yet few have experienced it. European Space Agency astronaut Samantha Cristoforetti explains that suction is key in the weightless environment aboard the ISS. There is a hose with suction for urine and a seat with a bag attached for feces.

NASA astronaut Suni Williams says the seat is a little small, so good aim is important. And while the suction should keep things going in the right direction,” messes do happen: “Sometimes things get a little out of control if you are out of control yourself, flying around.” For those messes, there is a variety of toilet papers and wipes. According to Williams, in case anyone was wondering, the Russian wipes are “a little bit coarse.”

Astronaut Samantha Cristoforetti of the European Space Agency shows off the tube for peeing aboard the ISS. ESA

Chris Hadfield, also a NASA astronaut, says there is a seatbelt to keep people in place, if need be. And when everything is done, the pee is recycled and the poop is freeze-dried in the vacuum of space to kill the bacteria and stored until it is sent to burn up in Earth’s atmosphere. “So the next time you see a beautiful shooting star going across the sky, that’s what it might be.”

Although Fischer said he is worried about pooping space, puking is less of a concern.

“I pretty much can’t get sick here on Earth — you can do things to me that would make a Billy goat puke, but after being a fighter pilot and test pilot, it just doesn’t bother me,” he said. But he is training just in case, because “you can never tell who will get sick on orbit.”

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