In between the news about water on Mars, clues of life on Jupiter or new stars being formed at our galaxy's edge, there is a less glamorous side of space exploration: what to do with astronauts' urine!
Human waste on long-term journeys into space makes up about half of the mission's total waste.
Recycling it is critical to keeping a clean environment for astronauts.
Rather than ejecting astronauts' pee into space, scientists are now developing a new technique that can turn this waste burden into a boon by converting it into fuel and much-needed drinking water.
"When onboard water supplies run low, treated urine can become a source of essential drinking water, which would otherwise have to be delivered from earth at a tremendous cost," explained NASA researcher Eduardo Nicolau.
Previous research has shown that a wastewater treatment process called forward osmosis in combination with a fuel cell can generate power.
The researchers collected urine and shower wastewater and processed it using forward osmosis - a way to filter contaminants from urea - a major component of urine, and water.
Their new Urea Bioreactor Electrochemical system (UBE) efficiently converted the urea into ammonia in its bioreactor, and then turned the ammonia into energy with its fuel cell.
"The system was designed with space missions in mind, but the results showed that the UBE system could be used in any wastewater treatment systems containing urea and/or ammonia," Nicolau said in a report that appeared in the journal ACS Sustainable Chemistry & Engineering.