The 156-day expedition, led by the Institute of Deep-Sea Science and Engineering of the Chinese Academy of Sciences, set sail from Sanya, Hainan province, on Dec 6. It covered more than 40,000 kilometers — equivalent to circling the Earth — and involved 83 researchers from China, Chile, Germany, Denmark, Canada and Spain.

The expedition focused on the Atacama Trench — which reaches depths of over 8,000 meters and holds significant scientific value for biodiversity and geology — and the largely unexplored Mussau Trench in the western Pacific, an area key to understanding tectonic plate formation.

During the mission, China's domestically developed manned submersible Fendouzhe, carried by Tansuo 1, completed 63 dives, 50 of which exceeded 6,000 meters. The team collected a large number of biological and geological samples, as well as high-definition underwater footage, laying a solid foundation for multidisciplinary research in deep-sea geology, biology and environmental science.