Overview

• A Nature study analyzing 23 high-quality events reports seismic phases consistent with a solid inner core about 600 kilometers in radius, though some experts urge caution given data and modeling limits.
• A separate Science paper finds Mars’ mantle is highly heterogeneous, with fragments up to roughly 4 kilometers across interpreted as debris from giant impacts around 4.5 billion years ago.
• Researchers identified frequency-dependent delays and scattering in eight strong marsquakes, matching models of compositionally distinct lumps embedded throughout the mantle.
• InSight’s single seismometer recorded 1,319 marsquakes from 2018 to 2022, enabling first-of-its-kind interior probing but providing limited spatial coverage for global confirmation.
• The findings reshape views of rocky-planet formation and preservation, linking early magma oceans and Mars’ sluggish mantle convection to long-lived interior structure and motivating expanded seismic networks.