While not many of you have wondered about this, we are still sure some have and probably, the question is thrown around as well because Hank Green, scientist from Montana, has recently uploaded a video where he explains all there is to know about how toilets work in space.
Green explains about how suction systems are used to cater to the needs of astronauts and while some of the waste is made use of on ISS for life-essential systems, the rest goes back to Earth. Green says in his video; ‘As you might imagine, it is a little bit tricky.’
We make use of toilet seats that have a diameter of 12-28 inches whereas in space the astronauts must do with an opening that is about 4 inches wide. Restraints are used to hold astronauts down to the seat and this ensures that no waste escapes. In order to train astronauts for this, NASA has particular exercises and training sessions.
‘The toilet itself works like a vacuum cleaner, using differential air pressure to suck the solid waste away.’ For urinating the approach is different since male and female anatomy is different. Personal urinal funnels are employed and a unit is given to each astronaut that is attached to a hose adapter and upon using the funnel the urine is sucked out into a tank that is designated as wastewater tank. Green says; ‘Naturally there are different set-ups for male and female astronauts and it’s actually easier for the women. For male astronauts it’s a bit more difficult.’
ISS toilets are not cheap and do more than just keep the waste where it belongs. In 2008 astronauts were using a system that could purify and distil urine into water. NASA also has plans for generating electricity by using the urine – a process known as forward osmosis. Green concludes the video with; ‘Now if only we could find some equally useful thing to do with our space poop.’