Exploring the Hidden Structure of Planetary Bodies

Planetary bodies preserve the history of their formation and evolution not only on their surfaces, but also deep within their interiors. Although these internal regions cannot be directly observed, their properties can be investigated by studying how a planet or moon rotates, deforms, and responds to the distribution of mass on and beneath its surface.

This talk presents how measurements of gravity, topography, planetary rotation, and temporal variations of these geodetic quantities help reveal the hidden structure of planets and moons. By combining these observations with geological and geochemical information, the density and thickness of planetary crusts, the composition of surface and subsurface deposits, the mechanical behavior of mantles and icy shells, and the properties of deep cores can be tightly constrained or inferred.

The presentation follows this approach across planetary bodies that are central to current planetary science investigations, including Mercury, Mars, Venus, Europa, and Enceladus. These worlds provide complementary examples of how surface observations can be connected to deep interior processes.

Through this perspective, geodesy and geophysics become powerful tools to connect the visible surface of a planet or moon with its hidden interior, helping us understand how planetary bodies formed, evolved, and continue to change over time.