MK sports known as the one-eighth vacuum chamber and overall installation system. Photo: Courtesy of the Hefei Institutes of Physical Science, Chinese Academy of Sciences" src="https://www.globaltimes.cn/Portals/0/attachment/2025/2025-03-09/00b127d7-b74a-4395-9b75-dcdea8db0362.jpeg" />

A critical system of China's next-generation "artificial sun," known as the one-eighth vacuum chamber and overall installation system. Photo: Courtesy of the Hefei Institutes of Physical Science, Chinese Academy of Sciences

China has hit another milestone in the development of its next-generation "artificial sun," with one of its key systems passing expert review and acceptance procedures on Sunday, achieving an internationally advanced development and operational capability standard.

The one-eighth vacuum chamber and overall installation system was developed by the Chinese Academy of Sciences' Institute of Plasma Physics (ASIPP). It is one of the 19 key subsystems of the Comprehensive Research Facility for Fusion Technolo-gy (CRAFT), a platform on which engineers develop and test the key components of fusion energy reactors, Xinhua News Agency reported.

According to CAS, the goal of developing an "artificial sun" is to replicate the nuclear fusion processes that occur in the sun, providing humanity with a limitless and clean energy source, and enabling exploration beyond solar system.

Resembling an orange slice, the newly approved system features a D-shaped cross-section with a double-layer shell and stands 20 meters tall. The vacuum chamber shell, made of ultra-low-carbon stainless steel, weighs 295 tonnes. In the future, eight of these "orange slices" will form a complete structure, housing plasma at temperatures exceeding 100 million degrees Celsius.

The vacuum chamber serves as the closest nuclear safety barrier to a reactor core, requiring extreme precision in terms of welding, structural integrity and magnetic permeability, said Liu Zhihong, a researcher at the Institute of Plasma Physics of CAS and the system's lead scientist, as reported by Xinhua.

By completing the one-eighth vacuum chamber, we have fully mastered the critical technologies needed for a complete toroidal vacuum chamber for future fusion reac-tors, Liu said, noting that the system's technology has also been applied to particle accelerators, precision machinery and electronics, per Xinhua.

The research team spent a decade overcoming technical challenges in their develop-ment of the system, securing more than 40 invention patents along the way.

According to Xinhua, this system not only provides a full-scale experimental platform for the installation, inspection, debugging, and remote operation research of internal components for future fusion reactor vacuum chambers, but also extends its applications to fields such as particle accelerators, precision machinery, electronic technology, and semiconductors.

China is making significant strides in fusion energy, with its Experimental Advanced Superconducting Tokamak (EAST) continuously upgrading experiments and setting new world records.