According to a recent genetic analysis, three previously unknown strains of bacteria were discovered growing on the International Space Station. The discovery could help scientists in developing better ways for growing food on Mars.
The study, which was published in the journal Frontiers in Microbiology, details how astronauts collected four strains of bacteria aboard the space station in 2011, 2015, and 2016. It was part of an ongoing surveillance program in which astronauts were tasked with monitoring eight different areas of the space station for bacterial growth.
Hundreds of samples have already been returned to Earth for analysis by astronauts, and thousands more are scheduled to be sent on return missions.
The newly discovered strains are members of the Methylobacteriaceae bacterial family, which is commonly found in soil and freshwater. These bacteria assist plant growth by fixing nitrogen and preventing pathogens.
So, how did these novel microbes make their way into the space station? They were most likely derived from plant-growing experiments that astronauts have been conducting for years aboard the ISS, such as the Advanced Plant Habitat, an automated growth chamber that grows plants in space for scientists to study back on Earth.
The new strains could be beneficial to space farming. After all, it’s already clear that the bacteria can survive the conditions of the space station, and the researchers wrote that the strains might possess “biotechnologically useful genetic determinants” that could help astronauts grow food on long-term missions, or on other planets.
“To grow plants in extreme places where resources are minimal, isolation of novel microbes that help to promote plant growth under stressful conditions is essential,” study authors Kasthuri Venkateswaran and Nitin K. Singh said in a press release.
“Needless to say, the ISS is a cleanly-maintained extreme environment. Crew safety is the number 1 priority and hence understanding human/plant pathogens are important, but beneficial microbes like this novel Methylobacterium ajmalii are also needed.”
To accelerate their understanding of how bacteria behaves in space, Singh and Venkateswaran proposed developing customized equipment that astronauts could use to analyze bacteria on the space station.
“Instead of bringing samples back to Earth for analyses, we need an integrated microbial monitoring system that collect, process, and analyze samples in space using molecular technologies,” they said. “This miniaturized ‘omics in space’ technology — a biosensor development — will help NASA and other space-faring nations achieve safe and sustainable space exploration for long periods of time.”
NASA hopes to send humans to Mars by the 2030s, while private companies like SpaceX want to get there sooner. Developing sustainable methods of growing food is critical for any Mars mission. This is primarily due to the impracticality of astronauts packing the food they will require for the journey, which will take 14 months roundtrip, not including time spent on the planet.
Astronauts must also maintain their health. Aside from the weight, the main issue with prepackaged food is that the nutrients break down over time. That is why, through projects like Veggie and the more recent Advanced Plant Habitat, NASA has been experimenting with growing various types of nutritious plants. These projects aid scientists in their understanding of the complexities of growing plants in microgravity, and how plants might grow on Mars.
But growing plants in space isn’t all about nutrition. NASA notes that plants are psychologically beneficial to people, both on Earth and in space. These psychological benefits might become especially important to astronauts on long-term missions millions of miles away from Earth.
Here’s how astronaut Peggy Whitson, who worked aboard the International Space Station, described seeing plants in space for the first time:
“It was surprising to me how great 6 soybean plants looked,” she told Space Daily. “I guess seeing something green for the first time in a month and a half had a real effect. From a psychological perspective, I think it’s interesting that the reaction was as dramatic as it was. […] I guess if we go to Mars, we need a garden!”