The common desire to travel to Mars raises entirely new constraints in terms of autonomy. So German scientists are working on ways in which urine could help astronauts grow food on Mars.
While most of the food for the International Space Station crew today is brought regularly from Earth, longer-duration, longer-range missions such as Mars will need an independent food supply.
Thus, at the German Aerospace Center (DLR), the team of plant physiologist Jens Hauslage is working on how to cultivate food directly into thespace by currently testing a system that involves a urine tank and a tomato plant, according to the BBC.
» The Earth is a closed biological system with plants that produce oxygen and food. Then you have the animals and microbes that produce all the degradation processes in the soil. », explains Jens Hauslage. » Without these systems, no way to ensure long-term sustainable living will be viable. « .
Using human urine and synthetic urine, the plant physiologist conducts experiments in the laboratory to try to recreate this cycle. For example, one experiment involves urine columns filled with pumice stones. In the holes that cover the pumice stones, there are colonies of bacteria that feed on the urine and convert the ammonia present in it into nitrites and nitrate salts: fertilizer.
Later this year a satellite will be launched with two miniature greenhouses. The satellite will simulate lunar gravity for the first six months to test the potential for growing vegetables on the Moon before simulating Martian gravity. A total of sixteen cameras will document the behavior of the tomato seeds that should germinate and grow in these greenhouses. Like the previously mentioned laboratory tests, these cultures under “satellite greenhouses” will involve bacteria which will feed on synthetic urine, providing fertilizer so that the tomatoes can grow.
If successful, these greenhouses could be used on lunar or Martian bases to provide food for future crews, explains Jens Hauslage in a press release.