Tim Peake, the first British astronaut in space since 1991, cleared up one of Earth's most burning questions for people in space in a video on Tuesday — how do you pee and poop?
In a very polite demonstration, Peak explains that "it really is quite simple." To pee, astronauts uncap a long tube and flip a switch to turn on the suction.
"For number two, the air flow does the same thing," said Peake. "Simple as that."
And what happens to all suctioned human excrement? It ends up in space and looks like a shooting poo star, according to NASA.
NASA created this nifty infographic to describe some of the health issues and "milestones" Scott Kelly, an American astronaut who is ending a one-year mission in space in March, has faced while aboard the ISS.
The agency explains Kelly's excrement "will burn up in the atmosphere and look like shooting stars."