Nobody has yet found the perfect formula for using urine and faeces to grow food-producing plants, but Crain and various other researchers are hard at work searching for the solution. “It’s still a matter of overcoming a mental block, because in the Middle Ages many people died from drinking water contaminated with human faeces.” With today’s technology, however, nobody would have to worry about that rather unpleasant scenario.
The American researcher spends her days in a greenhouse at the Strickhof research centre in Lindau, investigating which urine composition makes plants thrive most. The urine comes from the toilets at Eawag, the Swiss Federal Institute of Aquatic Science and Technology. The Eawag spinoff Vuna then processes it into the liquid fertilizer Aurin.
One of the biggest problems, says Crain, is that the urine contains high levels of salt, which many plants don’t like. As well as tolerating salt, the plants she chooses must also be efficient in converting CO
2
to oxygen and provide adequate nutrition and clean water for the astronauts living inside a Martian base. Crain is currently experimenting with the soybean.
Moon habitat on the Matterhorn
Establishing a permanent base on an alien planet is also one of the goals of the interdisciplinary student project IGLUNA, which is hosted by the Swiss Space Center. The IGLUNA challenge focuses specifically on gathering students to collaborate in a space-related project and demonstrate a potential moon habitat. Students from all over Europe are investigating what permanent lunar housing might look like and exploring the various technologies that could enable people to live in an extreme environment. The first components of such a habitat are now on public display inside the Glacier Palace at the Matterhorn Glacier Paradise and in Zermatt town centre, featuring contributions from a total of 20 teams from 9 European countries.
The individual projects cover many of the challenges of living on the moon, including how to produce clean air, drinking water, food and energy. They also encompass technologies designed to make navigation easier and improve astronauts’ well-being. “The universe provides students with a fantastic source of motivation and inspiration,” says Tatiana Benavides, manager of the Swiss Space Center hub at ETH Zurich and coordinator of the project.
The question of when we will see the first humans living in a permanent base on the moon or Mars is still very much up in the air. Fortunately, though, many of the technologies that researchers are developing with the goal of exploring alien planets also have their uses on Earth. For example, the urine-based fertiliser that ETH doctoral student Grace Crain is testing for space deployment could also be used on our own planet. And it would be nothing short of an agricultural revolution if it could one day replace chemical fertilisers.
Perhaps, in the end, the primary result of our romantic imaginings of life on another world might be to help us survive on our own planet. Yet that doesn’t rule out the possibility of humans eventually ending up settling on Mars, whether temporarily or permanently.
Sometimes science fiction turns into reality quicker than we might expect, upsetting all our established certainties in the process. When Johannes Kepler dreamed up his journey to the Moon in
Somnium
in the early 17th century, his main goal was to convince his readers that the Earth was not the centre of everything human and divine. Just one year later, he published the work
Astronomia Nova
, nowadays regarded as one of the first scientific proofs that the Earth moves around the Sun – and not vice versa.