Chinese astronauts aboard the Tiangong space station are studying anaerobic archaea in an experiment to determine if some of Earth's early forms of life can handle a simulated cosmic environment.
Shenzhou 18 crewmembers — commander Ye Guangfu and crewmates Li Cong and Li Guangsu — have been aboard the Tiangong space station since late April and have been busy conducting spacewalks and running experiments.
That scientific work includes research on space radiation damage and adaptability of anaerobic archaea, as a newly released video shows.
The archaea are a domain of single-celled organisms and one of Earth's oldest lifeforms. The archaea used in the Tiangong experiment consume hydrogen and carbon dioxide, in turn producing methane as a waste product.
The research aims to test their survival under Mars-like conditions and extreme cosmic radiation, contributing to the search for alien life, according to a report from Chinese state-run broadcaster CCTV.
Methane, a potential biomarker but also a gas produced by geological processes, has been detected on Mars a number of times and is of great interest to scientists. Similar experiments have been sent to the International Space Station (ISS) as part of research into the potential for life to exist beyond Earth.
The anaerobic archaea were delivered to the space station aboard the Tianzhou 7 cargo spacecraft earlier this year and have been housed in a small centrifuge module aboard Tiangong.
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Meanwhile, Ye Guangfu and his crew have been working on a wide array of other experiments and maintenance tasks. This includes replacing samples in fluid physics cabinets and containerless cabinets, performing vacuum operations in the combustion chamber and conducting experiments related to microgravity fluid physics, combustion science and space materials science.
Other recent tests include pharmacokinetic studies to assess the impact of long-duration spaceflight on the human body and to provide reference for in-orbit medication, according to CCTV.
China completed the construction of Tiangong in late 2022 and aims to keep the orbital outpost permanently occupied and running experiments for at least a decade. The incoming Shenzhou 19 astronauts are expected to launch to Tiangong around November. They will take over from the current crew, who will return to Earth after a few days of sharing the space station.