Simulating tidal stresses on satellites using SatStressGUI: Now with Polar Wander
Résumé
Some satellites of our solar system are old and heavily cratered while others are observed to be presently active or recently tectonically deformed. Many of the potential sources of stress which can deform satellites are driven by the tidal deformation the moons experience as they orbit their parent planets. Other plausible sources of global-scale stress include, nonsynchronous rotation, volume change induced by the melting or freezing of a subsurface layer, orbital obliquity, or polar wander. We turn to computer modeling to correlate observed geologic features to the possible stresses that created them. Here we demonstrate our recent enhancements to our open source SatStressGUI model. SatStressGUI computes stress vectors and Love numbers for diurnal tidal stresses, nonsynchronous rotation, ice shell thickening, obliquity, and polar wander. The program generates stress plots and lineaments that predict where fracturing should occur. We have expanded on SatStressGUI by adding features such as the ability to batch process stressing mechanisms, generate cycloid-style lineaments, and calculate stresses resulting from polar wander. Here we demonstrate our recent enhancements to SatStressGUI and its abilities, by comparing observed features on Enceladus and Europa to modeled stressing mechanisms.