The surface of an object encodes information on fundamental properties such as its composition and thermochemical history. However, mapping observed signatures back to such properties requires unraveling the relative roles of internal (e.g. geological) vs. environmental (e.g. radiation or bombardment) processes. Thermal emission at millimeter wavelengths arises from the near-subsurface; when combined with infrared datasets sensitive to the uppermost surface layer, temperature and material properties can be resolved as a function of depth over the depths where different processes dominate. This talk will highlight two cases where multi-wavelength datasets are informing our understanding of surface processes acting on Solar System bodies. At the galilean satellites of Jupiter, thermal datasets at infrared through mm wavelengths reveal the near-surface density profile, indicate the effects of plasma bombardment and of surface refreshing due to impacts, and would be sensitive to localized enhancements in internal heat if present. At the large stony and metallic asteroids, millimeter measurements constrain the abundance and form of the metallic component, while multi-wavelength measurements reveal the presence (or absence) of variations in composition with depth and constrain the scattering properties. Such measurements collectively inform our understanding of planetary surface environments and enable increasingly strong connections between observed signatures and the underlying processes at work.
The video of this talk is available here .