Welcome to brain Stuff from How Stuff Works, Hi brain Stuff Lauren Vogel bomb here. A manned mission to Mars might take around six months. Suffice it to say, when meal times roll around, astronauts won't be dialing up delivery pizza and root. Instead, they may be eating nutrition derived from their own fecal matter, a concept that would save on cargo, space and wait while maximizing materials already found
on the spacecraft. At Penn State University, scientists are developing a system that leverages certain types of microbes that convert human solid waste into protein and fat Latin foods. Researchers, for better or Worse, have already called the result a microbial goo that's sort of reminiscent of vegemite, a comparison that seems unlikely to please vegemites corporate executives. Because it's difficult and time consuming to grow food in space, astronauts
have to rely on items in their closed environment. The lynch pin of the system is anaerobic digestion, which can break down certain materials with the need for oxygen. It's a common process for reducing municipal waste on Earth. In tests, the digestion process produced methane gas. That gas turns out to be useful in growing a microbe called Methylococcus capsulattice, which is already used for animal feed pellets and contains
about fifty protein and thirty six percent fat content. According to the National Academy of Sciences, humans function best when they ingest nutrition with about fifty percent carbohydrates, twenty percent fat, and ten to thirty protein, So the goose still has a ways to go before it can count as an ideal food source. The tests relied on substitute liquid and solid waste instead of actual human wastes. When the real thing is introduced, there will also be concerns about pathogens
that could cause illnesses. That's where tweaking the pH levels and or temperatures may help. Tests showed that by increasing the system's temperatures to around a hundred and fifty eight degrees fahrenheit that's seventy degrees celsius, most germs were eliminated, yet the nutritious microbe Thermois aquaticus survived. Alternately, they raised the alkalinity of another batch and found that bacteria called halo Monus deciderrata still managed to proliferate, while germs did not.
The team borrowed concepts from commercial aquarium filters that use fixed film filters to neutralize fish waiste. The filters incorporate a bacteria laden film and were adapted by researchers to accommodate methane production. The result solid waste can be treated in a matter of hours instead of days plus. Because the system is self contained, it really doesn't require much babysitting other than you know, the necessary inputs. But there's
also the matter of taste. Lisa Steinberg, the lead author on the study, says that the bacteria could be mixed with other materials and flavorings to make it more palatable. She said in an email, it's nearly certain that there would be plants grown in conjunction with this food stuff, which would provide additional flavors and textures. And what about the potential psychological issues associated with consuming a material of
such dreary origins, Steinberg said. Astronauts ready have to drink their own processed urine, so they're probably accustomed to things being done differently in space than on Earth. Some astronauts on the International Space Station do already recycle some of their urine. Poop, on the other hand, has a more spectacular ending. It's blasted into space, caught an Earth's orbit, and then burns up like a shooting star on reentry. Yes, in space, poop has historically been a problem. Maybe now
poop will be part of the solution. While these still experimental concept may not exactly fire up astronauts appetites, it may eventually provide sustenance to space explorers who have a limited buffet options among the stars. Today's episode was written by Nathan Chandler and produced by Tristan McNeil. For more on this and lots of other tasty topics, visit our home planet, how stuff Works dot com.