Human urine is already the main source of water for astronauts working aboard the International Space Station. This is made possible by a complicated system that recycles water from sweat, washing, and toilet waste. But can it be realistically used to grow food to sustain colonies on Mars? After all, space travelers can't live on protein bars alone.
The challenge, Hauslage suggests, is to re-create the elements on Earth -- oxygen and microbes, essentially -- that will enable a remote colony to grow food.
Much of the urine Hauslage uses is artificial, but some comes from human donors. Oddly enough, with all the urine in Hauslage's lab, there's not much of a stench.
“The degradation of urine into carbon dioxide and ammonia is really fast,” he explains, “and the bacteria inside our filters are fast too.”
Later this year, a satellite with two small greenhouses will be launched to see how the tomatoes fare in space.