The South Polar Terrain (SPT) of Enceladus is a site with eruptions of gas and water ice particle plumes, which indicate internal geodynamic activity. These eruptions are located along a series of tectonic structures, that is, the Tiger Stripe Fractures (TSF), which are composed of regularly spaced, linear depressions. The SPT is surrounded by sinuous chains of ridges and troughs (the Marginal Zone). To unravel the tectonics that affect the region and its evolution, we performed specific structural mapping and quantitative analyses of brittle features from remotely sensed images. The results are consistent with a block rotation model, in which several tectonic regimes coexist. The TSF are left‐lateral strike‐slip faults that bound rigid elongated blocks. The blocks rotate clockwise and are enclosed in a regional scale right‐lateral kinematic framework expressed in the Marginal Zone. These two opposite and complementary kinematic regimes induce transtensional and transpressional regimes within the SPT. An evolutionary tectonic model is proposed for the past and future evolution of the SPT. This model confirms the role of tectonic‐related kinematics in icy satellites and contributes to preparations for future missions.

The formation of layered mounds on Mars remains a major topic of debate, with the relationship between their deposition and chemical alteration a major aspect still to be constrained. The association these deposits have with hydrated minerals indicates aqueous processes were active in their past, however the extent and duration of this aqueous period has yet to be fully realized. We studied compositional, stratigraphical, and structural characteristics of two separate layered deposits within Becquerel crater, Arabia Terra, to constrain their origins and the intensity of past aqueous activity. We find that due to key differences in composition, layering, and deformation between the two deposits, the timing of important depositional changes within Becquerel can be identified. We propose a scenario involving differences in fluid expulsion intensity and water level between the two layered deposits, in which diverse depositional and post‐depositional environments were able to form. Furthermore, internal collapsing and deformation of the main mound might reflect that fluid upwelling persisted below the mound after formation. Determining the relationship between these two deposits is an important step in unraveling the past climate of Arabia Terra, and more broadly Mars. The evidence of protracted fluid expulsion represents a unique opportunity for future missions searching for signs of past life.

In order to make inferences on the geodynamics of Antarctica, geodetic and gravimetric maps derived from past and new observations can be used. This paper provides new insights into the geodynamics of Antarctica by integrating data at regional and continental scales. In particular, signatures of geodynamic activity at a regional extent have been investigated in Victoria Land (VL, Antarctica) by means of Global Navigation Satellite System (GNSS) permanent station observations, data from the VLNDEF (Victoria Land Network for Deformation control) discontinuous network, and gravity station measurements. At the continental scale, episodic GNSS observations on VLNDEF sites collected for 20 years, together with continuous data from the International GNSS Service (IGS) and Polar Earth Observing Network (POLENET) sites, were processed, and the Euler pole position assessed with the angular velocity of the Antarctic plate. Both the Bouguer and the free-air gravity anomaly maps were obtained by integrating the available open-access geophysics dataset, and a compilation of 180 gravity measurements collected in the VL within the Italian National Program for Antarctic Research (PNRA) activities. As a result, new evidence has been detected at regional and continental scale. The main absolute motion of VL is towards SE (Ve 9.9 ± 0.26 mm/yr, Vn −11.9 ± 0.27 mm/yr) with a pattern similar to the transforms of the Tasman and Balleny fracture zones produced as consequence of Southern Ocean spreading. Residual velocities of the GNSS stations located in VL confirm the active role of the two main tectonic lineaments of the region, the Rennick–Aviator and the Lillie–Tucker faults with right-lateral sense of shear. The resulting VL gravity anomalies show a NW region characterized by small sized Bouguer anomaly with high uplift rates associated and a SE region with low values of Bouguer anomaly and general subsidence phenomena. The East and West Antarctica are characterized by a different thickness of the Earth’s crust, and the relative velocities obtained by the observed GNSS data confirm that movements between the two regions are negligible. In East Antarctica, the roots of the main subglacial highlands, Gamburtsev Mts and Dronning Maud Land, are present. The Northern Victoria Land (NVL) is characterized by more scattered anomalies. These confirm the differences between the Glacial Isostatic Adjustment (GIA) modeled and observed uplift rates that could be related to deep-seated, regional scale structures.