Two studies published on the 25th in Nature have found that Mars' liquid iron core may be enveloped by a layer of completely molten silicate. The research results propose a new explanation for the interior of Mars, suggesting that the Martian nucleus is smaller and denser than previously thought. The analysis of seismic experimental data on the internal structure of the NASA Insight lander in 2021 shows that Mars has a large but low density nucleus composed of liquid iron and light elements such as sulfur, carbon, oxygen, and hydrogen. The results also show that the proportion of light elements in the Martian nucleus is higher than the estimated abundance of these elements in the early stages of Martian formation history. The team from the Swiss Federal Institute of Technology in Zurich combined the latest batch of Martian seismic signals with first-principles simulation calculations and geophysical models for analysis, and estimated the size and composition of the Martian nucleus. These two studies have found that there is a layer of nearly molten silicate rock about 150 kilometers thick around the liquid iron core on Mars, whose top was previously mistaken for the surface of the Mars core. The reduction in the radius of Mars' nucleus means that its density is higher than previously estimated by the Insight study. These estimated results are more consistent with the current understanding of Martian chemical abundance. In a news and opinion article published simultaneously, the evaluation result is "currently the most accurate estimation of the structure of the Martian nucleus and mantle", and it is pointed out that the research results have enhanced people's understanding of the formation and composition of terrestrial planets. (New News Agency)