NASA has found that the surface of the ISS is absolutely covered in bacteria. The space agency has made a comprehensive catalogue of all non-human life aboard the ISS, and the list is long. Understanding precisely what can live in the intense conditions of space will help future missions plans for safety and could even begin to form the basis of new kinds of space food.
The surprising depth of bacterial biodiversity is partly thanks to a lack of competition. Dr. Kasthuri Venkateswaran, at the NASA Jet Propulsion Laboratory (JPL), the corresponding author said:
"Specific microbes in indoor spaces on Earth have been shown to impact human health. This is even more important for astronauts during spaceflight, as they have altered immunity and do not have access to the sophisticated medical interventions available on Earth. In light of possible future long-duration missions, it is important to identify the types of microorganisms that can accumulate in the unique, closed environments associated with spaceflight, how long they survive and their impact on human health and spacecraft infrastructure."
Bacteria similar to a gym or hospital
After examining environmental samples from surfaces in the ISS and air locations, the researchers found that microbes on the ISS were mostly human-associated. The most prominent bacteria present aboard the space station were Staphylococcus (26% of total isolates), Pantoea (23%) and Bacillus(11%).
On Earth, these bacteria are most commonly found in gyms, offices, and hospitals that show the ISS isn’t so different from other densely human occupied built environments. A focus of the study was to examine how these bacteria might contribute to illness in astronauts.
Astronaut health a big priority
The human body undergoes many changes when in space including an altered immune system. Understanding what bacteria are about is critical to planning for the good health of future crews.
"Whether these opportunistic bacteria could cause disease in astronauts on the ISS is unknown. This would depend on a number of factors, including the health status of each individual and how these organisms function while in the space environment. Regardless, the detection of possible disease-causing organisms highlights the importance of further studies to examine how these ISS microbes function in space,” said Dr. Checinska Sielaff, first author of the study.
Research to help Earth dwellers too
Samples were located from eight locations inside the ISS including the viewing window, toilet, exercise platform, dining table and sleeping quarters.
Bacteria were collected during three flights across 14 months to understand how the microbial and fungal populations differed between locations and over time. Temporal differences may be attributed to the changes of crew members aboard the station.
The results will be used by NASA for further research including applications for bacteria defense on Earth.
“Our study provides the first comprehensive catalogue of the bacteria and fungi found on surfaces in closed space systems and can be used to help improve safety measures that meet NASA requirements for deep space human habitation. The results can also have significant impact on our understanding of other confined built environments on the Earth such as clean rooms used in the pharmaceutical and medical industries,” concludes Dr. Venkateswaran.