Apparently this is one of the most common questions that astronauts get asked. At first this may seem like a question from a giggling teenager. However, when you give it more thought it is a very good question. We take the benefits of gravity for granted and especially so when it comes to using the bathroom. Gravity of course helps everything to head in the right direction and that is the end of the matter. Yet, if there is no gravity then this is a real problem!
Using a seat belt and flushing!
Yes you read it correctly. The first important addition to the inter-galactic toilet is a good old fashioned seat belt so that you can strap yourself to the toilet. This is to stop the astronaut floating off whilst carrying out his business. Second, there is a suction device that is used to carry away fluids separately and also solids separately. This suction is a little bit like the flush on some trains and aeroplanes. The only difference is that the suction is constant. Once the matter has been collected, it is exposed to the space atmosphere which basically freeze dries it. This solves the problem with odour. At a later convenient time the waste is ejected into space into the earth’s atmosphere and burns up. So the last time you thought you made a wish under a shooting star it may actually have turned out to be a pooper!