China’s Experimental Advanced Superconducting Tokamak (East) nuclear fusion reactor has breached a major fusion limit by firing plasma beyond its usual operational range, advancing humanity's slow progress towards near-limitless clean energy.

The East reactor, dubbed the “artificial sun”, kept plasma – the high-energy fourth state of matter – stable at extreme densities, which was previously seen as a major obstacle in the development of nuclear fusion, according to a statement released by the Chinese Academy of Sciences.

“The findings suggest a practical and scalable pathway for extending density limits in tokamaks and next-generation burning plasma fusion devices,” study co-lead author Ping Zhu, a professor in the School of Electrical and Electronic Engineering at the University of Science and Technology in China, said in the statement.