Overview

• The Chinese-led team reanalyzed NASA InSight seismic data and focused on about 23 relatively weak marsquakes recorded by the lone lander.
• The inner core’s radius is estimated at around 600 km, with a surrounding liquid outer core that may extend to roughly 1,800 km from the planet’s center.
• Seismic travel times and densities point to an iron–nickel core likely enriched with lighter elements such as oxygen.
• The result revises earlier InSight-based models that favored a fully liquid core and strengthens the case for a past core dynamo and magnetic field on Mars.
• Experts caution the finding is provisional given single-station limits and urge confirmation with a network of seismometers, as InSight ceased operations in 2022.