Fig. 1
From: PIONEERS: a 6DoF motion sensor to measure rotation and tides in the Solar System
Schematic representation of the observables that can be measured with the 6DoF motion sensor developed by the PIONEERS programme, namely rotation variations (left panel) and tidal deformation (right panel). These types of observations are excellent tools for inferring the interior structure of Solar System bodies, represented here by Mars (left panel) and a possible interior structure of icy moons with a subsurface ocean beneath an icy crust (right panel). The bodies shown are not to scale