If you run out of gas on your way to Mars, the simple solution could be tossing back a few beers and letting nature take its course.
Back in the 90's, scientists discovered a startling kind of bacteria called anammox (anaerobic ammonium oxidation) that devours ammonium, the chemical in urine that gives it its particular pungency, and spits out hydrazine, a propellant used in many space vehicles.
Obviously, this caused quite a stir. These bacteria could potentially take human waste, useless aboard a spacecraft, and convert it to fuel. Unfortunately, it was quickly revealed that the bacteria were nowhere near efficient enough at the conversion to produce any sort of usable or useful quantity of fuel, and the furor died down.
Now, scientists at Radboud University Nijmegen in the Netherlands have announced that they have isolated and identified the particular protein complex that allows these anammox bacteria to do their stuff, and this new knowledge could allow researchers to make a better and more efficient version of the bacteria.
Professor of microbiology at the university's Institute for Water and Wetland Research, Mike Jetten, has stated that the amount of hydrazine produced by the bacteria is "nothing like enough to get a rocket to Mars," but that the new research could change that. "Now we are accurately determining the crystal structure of the protein complex," he said, "Perhaps we can improve the production process if we have a better understanding of how the protein complex fits together."
So maybe we won't be flying urine-fueled spaceships anytime soon, but who knows? The future could be filled with trips to Mars and beyond, all powered by something we've been casually flushing away for millenia.
And if future astronauts eat too much asparagus, it could be a strange-smelling future indeed.