Scientists Find New Space-Adapted Bacteria Aboard Tiangong Space Station

Scientists have identified a new type of bacteria capable of withstanding harsh space conditions. The bacteria, retrieved from samples obtained during the Shenzhou 15 crewed mission, appear to have survived several months aboard China's Tiangong space station in 2022 and 2023.

Researchers aboard the Tiangong space station and the International Space Station (ISS) regularly test their orbital quarters for bacteria. While bacteria are bound to be present anywhere humans hang out, it's a good idea to capture snapshots of a microbial community at a given time: Astronauts get to find out which bacteria might go to battle with their weakened immune systems, and planetary scientists get to monitor how contaminants might reach a separate space body if a crew isn't careful. It's a procedure that benefits virtually everyone involved in space exploration.

The microbes found in these samples are often a known quantity. But every now and then, a new species of bacteria enters the scientific canon. Such is the case with Tiangong, which housed Niallia tiangongensis: a Gram-positive, rod-shaped bacteria that hangs out in the air. 

The new bacteria is detailed in a peer-reviewed paper for the International Journal of Systematic and Evolutionary Biology. According to the researchers, who analyzed the samples after Shenzhou 15 returned to Earth in June 2023, N. tiangongensis (also known as strain JL1B1071T) is spore-forming. This survival mechanism allows a bacterium to become dormant in harsh environmental conditions; once it returns to a "friendlier" environment, the spore can germinate back into an active cell. N. tiangongensis might also be capable of "biofilm formation, oxidative stress response, and radiation damage repair, thereby aiding its survival in the space environment," the researchers note.

This is the first time a new type of bacteria has been found on Tiangong, but other spacecraft are no stranger to novel microbes. Last year, scientists announced the discovery of a multi-drug resistant bacteria aboard the ISS, where the bacteria (Enterobacter bugandensis) was actively mutating to become "functionally distinct" from its former self. Researchers at NASA's Jet Propulsion Laboratory and its institutional partners also found 26 novel bacteria species in NASA's clean rooms—ultra-sterile environments aimed at preventing the transport of Earth bacteria to space—earlier this month.