Space toilets: How astronauts boldly go where few have gone before

A NASA astronomer explains how astronauts dispose of their, uh, dark matter.

MICHELLE THALLER: A really fun question is that when astronauts are in space they're not experiencing gravity, so how does digestion work? We sort of think of food moving down in our bodies, it seems that maybe gravity would have something to do with that. The amazing thing is that it really doesn't and this was one of the first things we discovered when we sent animals first and then people up into space. Some people wondered if you could swallow, if you could digest at all without the force of gravity. And it turns out that the act of peristalsis, the way your throat and your intestines squeeze themselves, will actually move food and water through your digestive system without gravity at all and you can even test that with people lying in hospital beds. When you think about somebody that's actually lying down, there's no force of gravity that's pulling food in one direction or the other. The human body is actually pretty good at moving food through without the force of gravity. Now other part of this is what happens when the food comes out the other end, because this is a natural thing that all humans do every day.

Well, you've now reached the wonderful science of space toilets. They actually act with suction. Now if you've ever been to the dentist's office and the dentist wants you to spit and he holds up a little cup with a tube attached to it and there's suction that takes the water down the tube. A space toilet acts very much that way; there's suction, there's a current of air that actually draws the waste down so it can be disposed of. And, honestly, sometimes it doesn't work perfectly. This is one of the things that astronauts have to deal with. When you think about the word 'floater', that has happened, where something escapes and you need to go get it. Some of the worst parts of human space flight in the very early days, like in Gemini all the way back in the 1960s, was people would collect their urine in a little plastic bag and sometimes they broke. So there have been some people up there and some very bad circumstances. Today, the toilet on the space station works very well and suction brings everything down and the best thing I can compare it to is the dentist's spit cup.

They actually have a little video camera so you can see if anything is floating around in the toilet before you get up. Yeah.

  • When nature calls in micro-gravity, astronauts must answer. Space agencies have developed suction-based toilets – with a camera built in to ensure all the waste is contained before "flushing".
  • Yes, there have been floaters in space. The early days of space exploration were a learning curve!
  • Amazingly, you don't need gravity to digest food. Peristalsis, the process by which your throat and intestines squeeze themselves, actually moves food and water through your digestive system without gravity at all.


Astronomers discover what makes the biggest explosions in space

New study figures out how stars produce gamma ray bursts.

University of Warwick/Mark Garlick
Surprising Science
  • Researchers find out how binary star systems produce gamma ray bursts.
  • Gamma ray bursts are the brightest explosions in the Universe.
  • Tidal effects created in a binary system keep the stars spinning fast and create the bursts.
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The joy of French, in a dozen maps

Isogloss cartography shows diversity, richness, and humour of the French language

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  • Isogloss maps show what most cartography doesn't: the diversity of language.
  • This baker's dozen charts the richness and humour of French.
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Want to be a better leader? Take off the mask.

The best leaders don't project perfection. Peter Fuda explains why.

Videos
  • There are two kinds of masks leaders wear. Executive coach Peter Fuda likens one to The Phantom of the Opera—projecting perfectionism to hide feelings of inadequacy—and the other to The Mask, where leaders assume a persona of toughness or brashness because they imagine it projects the power needed for the position.
  • Both of those masks are motivated by self-protection, rather than learning, growth and contribution. "By the way," says Fuda, "your people know you're imperfect anyway, so when you embrace your imperfections they know you're honest as well."
  • The most effective leaders are those who try to perfect their craft rather than try to perfect their image. They inspire a culture of learning and growth, not a culture where people are afraid to ask for help.

To learn more, visit peterfuda.com.