How do astronauts go to the bathroom in space? – Henry D., age 7, Cambridge, Massachusetts Whether you use a hole in the ground or a fancy gold-plated toilet, on Earth, gravity pulls your waste down and away from you. For astronauts, “doing their duty” is a bit more complicated. Without gravity, any loose drops or dribbles could float out of the toilet. That’s not good for astronauts’ health, nor for the sensitive equipment inside the space station. I study volcanoes on other planets, and I’m interested in how people can work in extreme environments like space. So how do you go to the bathroom in space or on the International Space Station? Carefully – and with suction.