NASA has launched a global challenge for engineers to design compact toilets that can operate in both microgravity and lunar gravity. Although space toilets already exist and are in use (at the International Space Station, for example), they are designed for microgravity only. NASA are looking for a next-generation model that will be smaller, more efficient, and capable of working in both environments.
The challenge guidelines list not only size and weight requirements, but decibel limits and ease of cleaning. It has to work for both men and women, and handle "simultaneous urination and defecation". The bathroom system also needs to be prepared for what NASA calls a diarrhea "event", conserve water, and be odour and contaminant free.
Lavatory facilities have come a long way from 1969, when the astronauts aboard the Apollo 11 Eagle Lander module had to relieve themselves in plastic bags secured with tape, which they then rolled up and took back to Earth. In fact, astronaut Alan Shepard, the first American in space, was forced to urinate in his pants on the launchpad in 1961.
NASA were understandably so consumed with how to get astronauts to and from the moon that they largely overlooked designing a suitable toilet for the Apollo missions of the 1960s and 70s. The first one was installed in a US space shuttle in the 1980s. There was technically a toilet on the Skylab space station in 1973, but it was a commode that looked like a hole in the wall and astronauts had to dry their own faeces in a special compartment.
The lack of bathroom planning has presented a messy problem for NASA and its astronauts in the past and solutions aren't easy. A variety of makeshift solutions have been sent into space over the years, including urination bags, roll-on 'cuffs', nappies, toilet seats with straps, and commodes. A Russian-made toilet in 2008 infamously converted crew members urine into drinkable water.
Engineers have until August 17 to submit their ideas for the challenge, which offers a total of $35,000 in prize money. It's probably for the best if plumbers, regardless of their level of expertise, don't apply.