To understand how Mars formed and how it has changed over time, it’s important to study the planet’s deep interior, its crust, mantle, and core. NASA’s InSight mission placed a seismometer on Mars that recorded 'marsquakes,' helping reveal details about the inner layers. But interpreting this data is difficult, because temperature and rock type can both affect how seismic waves travel, making it hard to tell them apart.

To improve our understanding, seismic data were combined with another type of information: how Mars reacts to electrical and magnetic signals, measured by the Mars Global Surveyor spacecraft. These signals depend on temperature and material properties, offering an independent way to explore the interior.

Several models of Mars’ interior were tested, using different rock compositions and considering whether a molten layer exists at the base of the mantle. Models without this molten layer often matched the electrical data better, especially when the mantle was hotter and the outer shell (lithosphere) was thicker.

This study shows that using both seismic and electromagnetic data provides a more complete view of Mars' interior. Future missions should aim to improve both types of measurements to better understand what lies beneath the surface.