A new species of bacteria has been discovered on China’s Tiangong space station that has adapted to the rigors of life in orbit, activating genes that help protect the microorganism from radiation and a lack of traditional food sources, with the genes responsible for these adaptations believed to have activated in only a matter of months, if not weeks. 

The new species, named Niallia tiangongensis after the Tiangong space station, was discovered in May 2023 during a routine sampling of on-board hardware as part of the China Space Station Habitation Area Microbiome Program (CHAMP). Similar to bacteria belonging to the genus Bacillaceae, N. tiangongensis is rod-shaped, aerobic (uses oxygen for its metabolism) and can transform into hardy endospores to help it survive harsh environments.

Although it is unclear as to how this new bacterium’s ancestor, assumed to be the soil-dwelling Niallia circulans, arrived on the space station, N. tiangongensis has adapted to be able to feed on gelatin in its new nutrient-poor environment; an enhanced ability to form biofilm, a gooey substance some bacteria use to form protective colonies; and an enhanced oxidative stress response and radiation damage repair, to compensate for damage to its DNA from both oxidizing free-radical molecules and ionizing radiation, respectively. Unfortunately, in gaining the ability to metabolize gelatin, N. tiangongensis appears to have lost the capacity to subsist on other nutrients.

Although this is not the first time a novel bacterium has been discovered aboard a spacecraft, the rapid evolution of microbes aboard spacecraft are a concern for space agencies, with the researchers that discovered N. tiangongensis stating that “understanding the characteristics of microbes during long-term space missions is essential for safeguarding the health of astronauts and maintaining the functionality of spacecraft.”

In particular, they are hoping an analysis of N. tiangongensis can offer more insight into how bacteria adapt in microgravity environments—even bacteria need to know which way is down—in order to help prevent or treat potential bacterial infections for space travelers, whether they be astronaut, cosmonaut or taikonaut.