If you are a sci-fi movie fan then you would definitely remember the struggle Matt Damon (played as Mark Watney in 'The Martian') had growing potatoes using his faeces as manure on the surface of Mars. Important thing was that he survived and eventually he did grow potatoes on Mars. Seems like some NASA-funded researchers took it too seriously and they have brought this imagination into reality.

Astro Watch

The researchers are working on turning human waste into nutrients and plastic for long-distance space travel. The idea is to use urine to feed a type of yeast (single-celled microorganisms), which can be genetically modified to make nutrients and even plastics for 3D printing tools.

Do not confuse it with the technology where urine is already recycled aboard the International Space Station(ISS) for drinking water for astronauts even though this system hasn't been embraced by the Russian side of the station yet.

And also not confuse it with the previous researches where researchers have proved that yeast can be genetically modified to produce all manner of substances. This includes omega-3 fatty acids, nutrients essential for health that the human body can't make, and even plastics, such as polyesters. That was a genetic modification of yeast and this time it is yeast feeding on carbon and nitrogen produced in human waste.

The project will help in freeing up much-needed space in the shuttle and stations when seen from the point of taking long journeys by recycling human waste. So now, astronauts will be using their waste from breath to pee to produce a variety of materials for lengthy space journeys. A weird but essential progress to survive longer in space.

This is what Mark Blenner, a synthetic biologist at Clemson University in South Carolina, who is leading the research has to say on the development.

He said, “Astronauts will need to be able to produce nutrients and materials they need during Earth-independent long-term space travel. They simply don't have the space to transport all possible needs – and certain nutrients, drugs, and materials can degrade over the course of three-plus year mission.”

Here is the little science behind it.

Fluorescent microscopy imaging of a Yarrowia lipolytica cell

Atlas of Science

Human urine is fed to various strains of Yarrowia lipolytica – a yeast commonly found in cheese. That means at a micro level this particular yeast would be on the carbon produced from our breath and the nitrogen in our pee.  This will help produce everything from vitamin supplements to polyesters.

Latest results prove that though carbon and nitrogen-eating yeast can only provide small amounts of polyesters and nutrients as of now, the team is working hard on increasing its output. They have already won funding from Nasa in 2015 and the project is only in its early stage.

Blenner further supported his argument emphasizing:

“As far as products, we have demonstrated the proof of principle and can produce polyester plastics, but this work is still preliminary. We are not making large enough quantities for practical application yet. Also, there is still a lot we don't know about how yeast grows in microgravity, in a lower pressure atmosphere, or with higher background radiation levels.”

On the other hand, Mark Hempsell, president of the British Interplanetary Society, did not seem that satisfied with the practicality of the whole approach.

He said, “I can't help feeling in most cases it is a lot lighter just to carry the spares than a giant piece of machinery that produces a rather crappy piece of plastic that might not be the best for the tool in the first place.”