Mercury research suggests lower silicon dioxide levels and hotter mantle

New research suggests that Mercury’s volcanic surface may contain significantly less silicon dioxide than previously estimated. A study led by Christian Renggli of the Max Planck Institute for Solar System Research indicates the abundance is approximately 37.4 percent by mass, which is up to 25 percent lower than earlier estimates from the MESSENGER mission that placed the value between 49 and 60 percent.

This lower silica concentration suggests that Mercury’s ancient lavas may have originated from a hotter, more extensively melted mantle. Because silica levels reflect how mantle rock melted and how magma changed before reaching the surface, these findings have significant geological implications for understanding the planet’s interior.

To address ongoing uncertainties regarding Mercury’s thermal and chemical properties, researchers have utilized Monte-Carlo simulations to model the coupled core-mantle thermal evolution. These models account for variables such as mantle composition—potentially consisting of forsterite and enstatite—and the specific fraction of silicon in the core. The upcoming orbital phase of the ESA/JAXA BepiColombo mission is expected to provide updated constraints to test these new estimates and refine models of Mercury’s interior structure.