How long can man exist in space without having a poo? Did men travel in space suits with poo on their bottoms and then return to Earth with Assteroids? Did man ever spend eight days in space so as to set foot on the Moon? Many people have discounted or accepted it on the basis of ’I don’t know enough about it’. I was an 11 year old boy when the Apollo Moon landings took place so I had not the intellect nor the resources to challenge it. My aerospace engineer dad put me right and told me it was not possible given the current technology. Over 50 years later I took the opportunity and I researched all the issues. I didn’t need to dig deep into science to discover that basic human bodily functions need to be performed in space. Even if defecation can be avoided for several days, urination can not. Eight days of urine in a space suit is a lot of liquid, almost 30 litres per person, That amount of fluid takes up a lot of room in a tightly fitting space suit. Eight days of urine from three men is almost 90 litres. Where would you store it in a tiny cramped space capsule? Even worse, how many days can you go without taking a poo?