Constraints on the interior structure of Phobos from tidal deformation modeling

Phobos is one of the two moons Mars, only other terrestrial planet to have companions. In spite certain common orbital characteristics between Earth’s Moon and Phobos, such as almost circular, low-inclination, synchronous orbits, origin Martian remains be understood. This unsettled state affairs reflects a scarcity data pertinent its interior structure bulk composition, both which hold key solving question provenance satellites. Drawing on importance means providing further constraints this problem, we construct series models in accordance with current observations determine their tidal deformation. The include homogeneous body, ice-rock mixtures, positive negative density gradients, layered models. To compute deformation precisely, solve three-dimensional elastostatic problem obtain full displacement field. For this, rely higher-order spectral-element method account for correct representation shape resulting field, accurately mesh figure by employing digital terrain model Willner et al. (2014). enable us distinguish models, also currently available geophysical (e.g., magnitude libration longitude, mean density, gravity moments inertia). Our results show that homogeneous, mixture, gradient are largely degenerate therefore difficult separate, but increase depth can differentiated from former families. From purely deformational point view, find largest occurs rim Stickney crater, rather than immediately at sub-Mars case where forces largest. These will considerable interest should provide important anchoring points future exploration envisaged Moons Exploration mission.