Temperature and conductivity in shocked bridgmanite (MgSiO₃) to 1.6 TPa

With the recent observation of an Earth-like rocky exoplanet by the James Webb Space Telescope, the need to characterize the interior components of planets becomes more urgent. To accurately model rocky exoplanets, the equation of state for planetary constituents must be constrained at pressures and temperatures relevant to mantles and cores. This work reports temperature and reflectivity measurements of shock compressed bridgmanite from 4,000 to 60,000 K, and these data are used to infer the melting curve and conductivity. Above 400 GPa, iron has a higher melting temperature than MgSiO3, implying that the mantle of rocky exoplanets with mass <2 M_E may solidify before the core. The conductivity of shocked bridgmanite rises significantly after melt to 2,200 Ω cm^-1. This suggests that a molten magma ocean may be conductive and produce a magnetic field.