Scientists onboard the Chinese space station, Tiangong, have successfully turned carbon dioxide (CO2) and water into life-sustaining materials.
Using a process called artificial photosynthesis, the team used technology that mimics the process plants use to turn sunlight, CO2 and water into oxygen and organic compounds.
The goal of this technology is to support astronauts on missions that could last years, such as to the Moon or Mars. This means creating a sustainable loop in space, where resources like oxygen can be generated from waste CO2, reducing the need for resupply missions from Earth.
The experiment was carried out on 18th January in one of the ‘space drawers’ in the aerospace basic test cabinet of the Mengtian module on China’s space station.
The process relies on a semiconductor catalyst, which absorbs sunlight and helps break down CO2 and water. In space, this technology captures the CO2 exhaled by astronauts and converts it into oxygen, making the air breathable.
By changing the catalyst, the system can produce other products from CO2, such as methane (for fuel) or formic acid (for synthesising sugars). This could be crucial for sustaining astronauts with food and fuel on long missions.
An example of in-situ resource utilisation, or ISRU, the technology works under normal temperature and pressure, unlike typical high-temperature CO2 reduction methods.
On Earth, the ability to capture and reuse CO2 in a sustainable way is a key challenge in various industries. The technology tested in space could offer insights into improving CO2 capture, recycling, and even turning it into valuable by-products.
The trial reflects China’s growing ambitions to establish itself as a ‘world power in space science’ by 2050.
“We have made breakthroughs,” Ding Chibiao, a vice president of the Chinese Academy of Sciences (CAS), said during a press briefing last year in Beijing. “But we still don’t have a great number of achievements, especially compared to developed nations.”
The country’s broader ambitions include establishing a research station on the Moon, sending astronauts there, and returning samples from Venus’s atmosphere by midcentury.
Other space agencies like NASA are also exploring ISRU technologies to support long-term space missions. NASA’s MOXIE experiment on Mars, for example, is testing the process of turning Martian CO2 into oxygen—crucial for future manned missions.
