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Introduction. The ASI Space Science Data Center (SSDC) has a long-standing experience in space data management. Among its tools, MATISSE (Multi-purpose Advanced Tool for Instruments for the Solar System Exploration [1]) was created in 2013 to search, visualize and analyze data from planetary exploration missions. MATISSE, whose v2.0 update [2] is available at https://tools.ssdc.asi.it/Matisse/, allows users to analyze data from different missions, such as NASA Messenger and NASA Dawn, and the possibility of visualizing the data directly on the 3D shape of the targets greatly helped in reaching stunning scientific results. The work here presented points at improving and expanding the functionalities of the MATISSE tool for the Mercury explorations, by including the possibility to merge together the outputs of a thermophysical code of Mercury surface and the study of planet’s surface from a geological point of view. MATISSE for Mercury exploration. The ESA-JAXA BepiColombo mission is the first European mission to Mercury; the spacecraft will study in detail the surface, the exosphere and the magnetosphere of the planet. We have developed a thermophysical model with the aim to analyze the dependence of the temperature of the surface and of the layers close to it on the assumptions on the thermophysical properties of the soil. The code solves the one-dimensional heat equation, assumes purely conductive heat propagation and no internal heat sources; the surface is assumed to be composed of a regolith layer with high porosity and density increasing with depth. Calculations have been carried out to analyze the thermal response of the soil as a function of thermal conductivity. The model has been also used to study the sodium content in the planet's exosphere, whose origin is under investigation [3]; the MESSENGER mission has measured the exospheric sodium content as a function of time, detecting an increase at the "cold poles" (so called because of their lower than average temperature). In order to study the effect of surface temperatures on the sodium content in the exosphere, the temperature distribution calculated with the code has been used together with an atmospheric circulation model that calculates the exospheric sodium content [4]. Figure 1. Total sodium exospheric content as function of time and true anomaly angle, calculated in two cases: surface temperature from the thermophysical code (red line), and reference temperature (T proportional to ¼ power of cosine of illumination angle, blue line). A simplified version of the thermophysical code is available to the scientific community through MATISSE and, therefore, it could be crucial to interpret the data acquired by the instruments on board the BepiColombo mission, especially if it is taken into account that, through MATISSE, it is possible to analyze the surface of Mercury with data from NASA Messenger based on queries looking for specific geological units (as is already possible for Mars, Mercury and Ceres). Thanks to the data from the MDIS (Mercury Dual Imaging System [5]) camera on board the MESSENGER, it was possible to create a global map of the planet's surface. The identified lithologies can be analyzed and subsequently uploaded to our MATISSE tool in order to have the possibility to study the surface of Mercury directly from the site. On MATISSE it will be possible to select the data not only with the usual geographical coordinate, but on the basis of geological maps, so that the user can analyze observational and modeled data collected on areas with well-defined geology that allow to study the effects of the heterogeneity of surface. Figure 2. MATISSE homepage and selection of parameters to be observed. Example of selection of the Hokusay crater on Mercury's surface. The possibility of studying the Mercury surface directly from the tool will allow not only to make a detailed study of the terrain but understanding its formation will help science to understand how the solar wind affects some materials. For this reason our work will allow planetologists and astrophysicists to have all the available data for the study of the planet. In collaboration with the PlanMap and GMap teams, we are currently working to include the geological units identified on the surface of Mercury in order to be ready with the data that will come from the Bepi Colombo mission in order to have everything you need to study this planet in depth. Next steps. We plan to add in the tool all geological units mapped by GMAP team on Mercury surface. Moreover we will expand in the tool the possibility of searching for data based on the morphologies that the user wants to analyze (e.g. craters, valleys). Another goal will be to expand the use of the tool, making it similar to the geographic information system (GIS). We will expand the possibility of selecting specific areas to be analyzed, having clear the geographical position of the data. It will also be possible to obtain topographic profiles, select more data to be observed. All these analyses will be performed directly on the 3D models. The inclusion of these functionalities in the tool could produce a sensible step forward in the study of planetary geology, with the possibility of better exploiting different datasets and taking also into account the collaboration of different teams already leaders in this field. References. [1] Zinzi A. et al. (2016) Astron. Comput., 15, 16-28 [2] Zinzi A. et al. (2019) EPSC-DPS Joint Meeting 2019, id. EPSC-DPS2019-1272 [3] Rognini, E., et al. (2022), Effects of mercury surface temperature on the sodium abundance in its exosphere, Planetary and Space Science, 212 [4] Mura, A., et al. (2009), The sodium exosphere of Mercury: Comparison between observations during Mercury’s transit and model results, Icarus, 200, 1-11 [5] Hawkins et al., (2007). The Mercury Dual Imaging system on the MESSENGER spacecraft, Space Science Reviews, 131, 247–338

Póster presentado en Europlanet Science Congress 2022 Granada, Spain 18-23 September 2022

Introduction: Despite the large amount of information from orbital and in situ missions, the characteristics and evolution of Mars’ early climate are still widely debated among the scientific community. Morphological evidence dating back to about 3-4 billion years ago, such as valley networks [1], and the presence of several hydrated minerals [2] seem to indicate that Mars once had a “warm and wet” climate with abundant water on the surface and possibly even an ocean in the northern lowlands [1-3]. These conditions eventually changed through time leading up to the hyperarid and cold planet we observe today. The area of Meridiani Planum (MP), located SW of Arabia Terra, is well known for retaining multiple evidence of past aqueous activity [4] and a varied hydrated mineralogy [5]. The majority of the terrains exposed in MP formed at the Noachian-Hesperian boundary [6], that is between two important epochs of Mars: the Noachian (4.1-3.7 Ga), where most of the evidence for water is found, and the Hesperian (3.7-3.0 Ga), which is characterized by increasingly water-limited conditions. Constraining the potential water environment at the NH boundary is fundamental to understand Mars’ early climate and its evolution. In this study, we select 7 craters in Northern MP (figure 1) showing evidence of NH sediment infillings with hydrated materials (e.g., clays and sulfates) to assess in detail the stratigraphic sequence of the mineralogical units and understand their origin and diagenetic history. The craters are roughly aligned SE to NW following the general slope of the area from the highlands to the lowlands. If Mars experienced a “warm and wet” period, MP would represent a transition zone between the subaerial alteration environment of the highlands and the subaqueous environment of the Martian ocean. Therefore, the area would be easily affected by climatic changes whose evidence should be retained in its sedimentary sequences. We show here some preliminary results from 2 out of the 7 craters selected for the study: 1) a 15-km-wide crater named Mikumi, centered at Lat. 2.45°N, Lon. 359.96°E; 2) an 18-km-wide unnamed crater centered at Lat. 4.25°N, Lon. 2.85°E. Figure 1: THEMIS daytime image of Meridiani Planum. Selected craters are evidenced with points. Name (if given) and coordinates of the center for each crater are also indicated with a label. Most of the craters are unnamed. The arrows indicate the two craters described in this abstract. Datasets and methods: We investigate the mineralogy of the craters’ terrains through CRISM [7] hyperspectral data cubes mainly in the range 1.0-2.6 μm. This interval retains part of the key spectral features of primary rock-forming minerals, which constitute the Martian crust, and of most minerals produced by secondary processes such as aqueous circulation and alteration (e.g., clays and sulfates). MOLA, THEMIS, CTX and HiRISE data are then used for morpho-stratigraphy and camera imaging. Results: Two types of clays (smectites) with different Fe/Mg content, polyhydrated sulfates and monohydrated sulfates are observed in both craters (figure 2). Fe/Mg-clay spectra (e.g., nontronite and saponite) show absorptions at around 1.4, 1.9 and 2.3 μm with additional overtones at 2.4 μm. The exact position of the 2.3 μm feature depends on the relative Fe/Mg content in the clay mineral. We find some areas with clays richer in iron (e.g., nontronite), showing this feature centered at 2.305 μm, and clays richer in magnesium (e.g., saponite) where the absorption is centered at 2.310-2.315 μm. In Mikumi crater, polyhydrated sulfates (Mg sulfate) and monohydrated sulfates (kieserite) are detected stratigraphically below the clay-bearing layer. For the unnamed crater, the stratigraphic relationship of the units is still to be investigated. Figure 2: (top) CRISM spectra of detected mineralogy. Fe/Mg clays (smectites) are from Mikumi crater, mono and polyhydrated sulfates are from the Unnamed crater. The spectra are extracted from FRT0000BEF5 and FRT00009B5A TRR datasets respectively. (bottom) Laboratory spectra of clays and sulfates from the CRISM spectral library [8] (Mg Sulfate ID: CJB366; Kieserite ID: F1CC15; Saponite ID: LASA51; Nontronite ID: NCJB26). Discussion and conclusions: Clays and sulfates on Mars appear to have formed at different times and under different climatic conditions [9]. Clays are usually associated to Noachian terrains and may have formed under alkaline conditions in a “warm and wet” ancient Mars, whereas sulfates are typically associated to Hesperian surfaces and may have formed under a dryer and more acidic environment. Therefore, sulfates are expected to be found stratigraphically on top of clays, as they should have formed later in Mars’ history. However, this distinction between a clay-rich Noachian and a sulfate-rich Hesperian oversimplifies the history of the aqueous chemistry and climate of Mars especially near the NH boundary. Our analysis suggests a stratigraphic sequence with interleaving clays and sulfates at the NH boundary. Similar stratigraphic sequences have also been observed in other areas of MP (Southern MP) by [5]. In the case of [5], a clay-bearing layer is overlain by other sulfates, generating a sulfate/clay/sulfate stratigraphic sequence. All this argues is in favor of several distinct climatic episodes pacing the NH climatic transition. The results obtained so far will be enriched by further analysis of these areas along with a thorough investigation of the remaining 5 craters selected. Acknowledgments: Featured CRISM data were downloaded from the Planetary Data System (PDS). This project is partially supported by Europlanet RI20-24 GMAP project. References: [1] M. H. Carr and J. W. Head (2010) Earth and Planet. Sci. Lett., 293, 185-203. [2] B. L. Ehlmann and C. S. Edwards (2014) Annu. Rev. Earth Planet. Sci., 42, 291-315. [3] R. A. Craddock and A. D. Howard (2002) JGR, 107 (E11), 5111. [4] R. M. E. Williams et al. (2017) GRL, 44, 1669-1678. [5] J. Flahaut et al. (2015) Icarus, 248, 269-288. [6] B. M. Hynek et al. (2002) JGR, 107 (E10), 5088. [7] S. Murchie et al. (2007) JGR, 112 (E5), E05S03. [8] C. E. Viviano-Beck et al. (2015) MRO CRISM Type Spectra Library, NASA Planetary Data System. https://crismtypespectra.rsl.wustl.edu [9] J. P. Bibring et al. (2006) Science, 312, 400-404.

Introduction: In the Martian North Polar Cap, troughs are formed and enlarged by the erosive action of katabatic winds, blowing perpendicularly with respect to steep edges of the cap. Along these valleys deeper layering of the polar deposits are often exposed making it possible to study the stratigraphy of the upper part of the polar cap [1]. We focused our attention on a 140 km long and 500 m high scarp located in the North-Western edge, facing Olympia Planum, and where part of the North Polar Layered Deposits (NPLD) are exposed. NPLD deposits are finely layered and laterally continuous sequence of light and dark strata with sporadic unconformities in between, whose periodicity has been attributed to climatic and orbital variations [2]. In the polar cap, Tanaka et al. [3] has distinguished different polar units by means of surface image interpretation, hence our scarp exposes Planum Boreum 1 unit overlapped by Planum Boreum 3 unit, both composed of variable ice/dust content, but different thickness. Putzig et al. [4] identified instead seven units inside the polar cap on the basis of the pattern of radar reflections in the radargram-based stratigraphy thanks to the data provided by SHARAD. The stratigraphic sequence of our interest correlates with the upper part of the packet-inter-packet sequence of the unit G by Putzig et al. [4]. The aim of our work is to relate the composition and stratigraphy of the visible layered deposits with the subsurface radar reflectors, using the data acquired by the NASA Mars Reconnaissance Orbiter instruments. Data selection: We performed stratigraphic and geomorphologic interpretation on images of the Context Camera (CTX) and High Resolution Imaging Science Experiment (HiRISE); band ratios and spectral signatures on a hyperspectral cube of the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM); subsurface reconstructions on radar reflectors obtained by the Shallow Radar (SHARAD). The integration of the results obtained by such a multi-score data-set underlies the possibility to join the SHARAD stratigraphy with the stratigraphic record recognisable at the surface including its compositional variability (Fig.1). Fig.1 – Data-set: MOLA DEM (a), CTX image (b), CRISM cube (c), HiRISE images (d, e) and SHARAD radargram tracks (f, g, h, i). Black rectangle in the North Polar Cap region shows the study area. Spectral analysis: Spectra for five Regions of Interest (ROIs) of about 50 pixels were acquired and are shown in Fig.2a-b. Fig.2 – (a) Regions of Interest over CRISM image detail; (b) Plot of five ROI average spectra: each colour line represents a ROI spectrum (continuum is removed). The exposed stratigraphy is composed of different amount of dry ice, water ice and basaltic dust [3]. Spectra A and B are well distinguishable, whereas the signatures of C, D and E appear similar, indicating comparable compositions. Spectrum A exhibits well developed water-ice absorption bands (1.5 and 1.95 µm), less development of same peaks might imply an increase of dry ice content. The 1 µm peak (water ice) is well visible in both A and B spectra, but less evident in C, D and E. Multiple absorptions at 1.65 and 2.06 µm, associated to CO2, are well visible in C, D and E. Other absorption bands (at 0.50, 1.02 and 2.30 µm for example) can be related to femic and aqueous alteration minerals. Spectrum A is similar to the signature of pure water ice, with less altered minerals, while C, D and E appear to be characterized by dry ice and femic minerals. Spectrum B appear to be transitional between these two end-members. Spectral indexes: Spectral indexes were produced using CRISM Analysis Toolkit (CAT) [5]. Indexes allowed us to create false colour images to highlight the presence/absence of specific minerals. Example of these are shown in Fig. 3 (see FED for the index definition). Fig.3 – Two false colour images created with spectral indexes (a) BDI1000VIS_BD15002_BD1435 representing ice compositions and (b) OLINDEX3_LCPINEX2_RBR to highlight mineral composition. Mapping and correlation to radar reflectors: Geological units were identified on CRISM and CTX data on the basis of morphology, composition, albedo and their stratigraphic relationship. Fig.4 displays the mapped units. Fig.4 – Geological map and relative units. WI-units: water-ice-rich deposits (blue), WF-unit: water ice and femic minerals deposits (light blue); DF-units: dry ice and femic minerals deposits (green); DI-units: dry-ice-rich deposits (yellow); Aeolian deposits (red); Gravitational deposits (purple). Fig.5 shows the geological units correlated with radargrams features. Variations of dielectric constant among strata are due firstly to presence of water ice in the surficial layers and dry ice in deeper ones, secondly to different amount of dust in radar units. These affect the signal reflectance: stronger if it is from water-ice layers. Additionally, high content of dust significantly decrease the radar signal, so units appear darker [4] [6]. The lines in Fig.5 represent lower contact of the geological units. Fig.5 – Correlation between geological units and radar reflectors. The colours of units are the same of geological map (vertical axis in time). Section track is shown in Fig.1. Discussion and conclusions: We provide a detailed compositional and geometrical characterization (using CRISM, HiRISE, CTX) of outcropping layered deposits of the North Polar Cap, to evaluate the potential for performing sound stratigraphic correlations with the subsurface reflectors identified in SHARAD radargrams. At a scale of single layers, compositional variations of basaltic dust content in the stratigraphic sequence were identified. This variability is visible especially in dry-ice-rich layers. Basaltic dust showed aqueous alteration, especially in water-ice-rich strata. Acknowledgments: We acknowledge support from the EU’s H2020 research and innovation program under grant agreement N° 871149 (GMAP). References: [1] Masse, M. et al. (2012) Earth and Planetary Science Letters, 317, doi: 10.1016/j.epsl.2011.11.035; [2] Byrne, S. (2009) Annual Review of Earth and Planetary Science, 37, doi: 10.1146/annurev.earth.031208.100101; [3] Tanaka, K. et al. (2008) Icarus, 196(2), doi: 10.1016/j.icarus.2008.01.021; [4] Putzig, N. et al. (2009), Icarus, 204(2), doi: 10.1016/j.icarus.2009.07.034; [5] Viviano-Beck, C. et al (2014), Journal of Geophysical Research, 119(6), doi: 10.1002/2014JE004627; [6] Lauro, S. et al. (2012), Icarus, 219(1), doi: 10.1016/j.icarus.2012.03.011.

Lava tubes, or pyroducts [1], are a peculiar type of lava caves originating from basaltic lava flows. These conduits are very efficient thermal structures that allow the lava to cover long distances before cooling down. Lava tubes, are typical features of lava fields found in volcanic-shield islands (e.g. Hawai’i, Canaries, Iceland, etc.) and intracontinental plateaus characterised by gentle slopes ( These structures are easily recognizable from the surface through the presence of skylights and roof collapses aligned in pit-chains, tracing the path of the underground conduit (Fig. 1). Analogous aligned collapses were seen on the surfaces of Mars and the Moon [2]. Thus, the great interest in studying large terrestrial lava tube systems is largely driven by their analogy with their extra-terrestrial equivalents. Figure 1: Comparison of lava tubes from different rocky bodies of the Solar System. From the left: Earth (Undara system, Australia), Mars (Arsia Mons region) and the Moon (Gruithuisen crater). The main difference between structures of different planetary bodies are due to intrinsic physical characters of the parental body and above all gravity. Indeed, a weaker gravity (as in the case of Mars and the Moon) results in higher effusion rates and, thus, larger lava flows and tubes (Fig. 1). This has led to pyroducts which are two or three orders of magnitude smaller in diameter on Earth (10 - 30 m) than on Mars (250 - 400 m) and the Moon (500 - 1100 m) [5]. Despite this different scaling, the largest lava tubes on Earth are considered to be very useful analogues to their extra-terrestrial counterparts. A clear understanding of how large pyroducts form and evolve remains elusive, even on Earth. Within this context, our work aims to identify the processes that shaped the formation of terrestrial lava tubes. Among the most studied pyroducts, the La Corona system (Lanzarote, Canary Islands, Spain) stends out for its geological context within the Canary Island Seamount Province (CISP) on which long-term and spatially focused volcanic activity developed over a poorly mobile tectonic plate. During the last 30 Ma, the absolute motion of the African plate has been nearly stationary (less than 20 mm/yr) [3]. This environment identifies the Canaries as one of the best terrestrial analogues of the Martian one-shell plate volcanism [4], and the impressive dimensions of La Corona lava tube (~9.7 km of total cave development, and a width reaching up to ~28 m for some of its sections) make it one of the most suitable lava tube for interplanetary analogies [6]. In order to understand the origin, evolution and degradation of the La Corona pyroduct, we have carried out a study of the satellite images of the northern region of Lanzarote, followed by field exploration of inner portions of the La Corona lava tube and adjacent areas. Combining terrestrial laser scanner (TLS) technology with field observations and geochemical analyses of the pre-existing lava enabled us to reconstruct the three-dimensional geometry of the lava tube system, the subsurface horizon through which it starts developing, and the volcanic series into which the pyroduct carved its path. What makes this inflated lava tube so interesting is the presence, between the flows the tube has crossed, of a red pyroclastic layer, resulting from the initial Strombolian activity of La Corona vent [7]. This weak layer of pyroclastic material played a major role in the development of the lava tube (Fig. 2), facilitating the emplacement of the inflation process and the excavation that followed [6]. By analogy, similar geological settings could be favourable for the formation of lava tubes on rocky bodies like Mars and the Moon since the volcanic sequences on such bodies can be frequently interleaved by either weak pyroclastic and regolith layers. Other influent parameters controlling erosion include slope variations of the paleo-surface (i.e., knickpoints), and the lava physical properties, both to be well investigated on terrestrial analogues to understand their role even on planetary contexts. Figure 2: Thermo-mechanical erosional stages of the lava tube in cross-sections. a) The primary effusive phase has covered the pyroclastic deposit of the initial Strombolian event; b) the inception of the tube by inflation starts exploiting the pyroclastic layer; c-d-e) progressive erosion and enlargement of the tunnel; f) post-cooling phase. On the walls are visible different layers of linings and flow ledges. The floor is covered by blocks and debris, remnants of the breaking down of the ceiling and lining walls. References [1] Coan, T. (1844). Missionary Herald. [2] Haruyama, J. et al. (2012) Trans. JAPAN Soc. Aeronaut. Sp. Sci. Aerosp. Technol. JAPAN 10. [3] Gaina, C. et al. (2013). Tectonophysics, 604, 4-25. [4] Meyzen, C. M., et al. (2015) Geol. Soc. London, Spec. Publ. 401. [5] Sauro et al. (2020) Earth-Science Rev. [6] Tomasi, I. et al. (pending) JGR – Solid Earth. [6] Carracedo, J. C. et al. (2003) Estud. Geol. 59.

Galileo Regio is a dark terrain of Ganymede extending approximately from 180°-120° W to 0°-60° N that shows high crater density and morphotectonic structures called furrows. Such structures are kilometric-scale brittle troughs bounded by high albedo rims and a low albedo floor, and arranged with circumferential and radial setting at the regional scale [1]. Furrows are generally interpreted as the remnants of a multi-ring impact basin similar to the Valhalla basin on Callisto [2]. Galileo Regio shows two main settings of the furrows, which allow their classification into two systems: the concentric furrows of Lakhmu Fossae system, which is crosscut by the radial furrows of the Zu Fossae system [3]. In addition, Galileo Regio shows local-scale structures that rework the pristine morphology of the Lakhmu Fossae furrows. In this contribution, we investigate the furrows of Galileo Regio at both regional- and local-scale to unravel the tectonic evolution of the dark terrain. We perform a structural mapping and geostatistical analyses of the furrows in Galileo Regio, identifying their hierarchy and tectonic setting originated by regional-scale kinematics. Structure attributes such as structure length, sinuosity, azimuth, spacing within the adjacent structures, have been quantitatively characterized and allow to perform the azimuthal distribution, the Length/Spacing [5] and the paleo-stress analyses [6]. Such analyses allow to identify the structural systems and to infer the past stress fields that affected Galileo Regio (maximum and minimum horizontal stress, i.e., SHmax and Shmin, respectively). A total of four structural systems have been recognized within Galileo Regio: i) the already known Lakhmu and Zu Fossae; and ii) the Lineated system and Precursor system, proposed by this work for the first time (Fig. 1). Such systems are the result of phases of the tectonic activity that affected Galileo Regio during the geologic history of Ganymede. We identify the sequence of such phases that allow to produce an evolutionary tectonic model (Fig. 2): i) t0 represents a NW-SE extension that formed the Lineated system; ii) t1 represents the impact that originated a multi-ring basin [3, 7], i.e., the Lakhmu Fossae; iii) t2 shows the extensional activity responsible for the formation of the light terrain of Uruk Sulcus [8] and for the formation of the extensional structures of the Precursor system; iv) t3 represents the kinematics consistent with the right-lateral transpression that has affected Uruk Sulcus [4] and formed the Zu Fossae; and v) t4 presents a right-lateral strike-slip that contributes to the formation of the Precursor system. The obtained results and the presented model will be used for the scientific preparation of dedicated high-resolution observations that will be taken with the JANUS instrument [9] onboard the JUICE mission [10]. Acknowledgments: The activity has been realized under the ASI-INAF contract 2018-25-HH.0. References: [1] Patterson, W. et al. (2010). Icarus 207,845–867; [2] McKinnon, W.B. and Melosh, H.J. (1980). Icarus 44 (2), 454–471; [3] Prockter, L.M., et al. (2000). Journal of Geophysical Research: Planets, 105(E9), 22519-22540; [4] Kersten, E., et al. (2021). Planetary and Space Science, 206, 105310; [5] Rossi, C., et al. (2018). Tectonophysics 749, 72–87; [5] Delvaux, D., and Sperner, B. (2003). Geol. Soc., London, Special Publications, 212(1), 75-100; [7] Hirata, N., et al. (2020). Icarus, 352, 113941; [8] Pappalardo, R.T., et al. (1998). Icarus, 135(1), 276-302; [9] Palumbo, P., et al. (2014). 45th LPSC Meeting. Abstract #2094; [10] Grasset, O., et al. (2013). Planetary and Space Science, 78, 1–21.

Data from NASA MESSENGER spacecraft highlighted that Mercury’s surface and composition are more varied than previously thought. Despite being the closest planet to the Sun, indeed, Mercury is rich in volatiles and its surface shows evidence of volatile-driven processes such as the formation of hollows and explosive volcanism. Even MESSENGER’s color-derived basemaps, moreover, highlight relevant color variations of the hermean surface possibly indicating age and compositional differences between adjacent materials. The ongoing mapping for the eastern H9 Eminescu quadrangle (22.5°N-22.5°S, 108°E-144°E) [1] led to a thorough knowledge of the area that allowed the definition of scientific targets of interest to be investigated by the SIMBIO-SYS cameras [2] onboard the ESA-JAXA BepiColombo mission [3] coupled with other instruments such as MERTIS, BELA, MGNS and MIXS. Proposed targets range from hollows to volcanic features, from craters and deformational structures and specific terrains and aim at shedding light on scientific questions concerning Mercury’s origin and evolution [4]. In particular, proposed targets aim to i) determine the abundance and distribution of key elements, minerals and rocks on the hermean crust, ii) characterize and correlate geomorphological features with compositional variations, iii) investigate the nature, evolution, composition and mechanisms of effusive and explosive events, iv) determine the formation and growth rates of hollows, the nature of processes related with volatile loss and their mineralogical and elemental composition of volatiles, v) determine the displacement and kinematics of tectonic deformations and the mechanisms responsible for their formation and vi) verify the occurrence of any detectable change in and around hollows and pyroclastic deposits since MESSENGER observations. Acknowledgements: We acknowledge support from the Italian Space Agency (ASI) under ASI-INAF agreement 2017-47-H.0. References: [1] El Yazidi et al., 2021, EPSC. [2] Cremonese et al., 2020, Sp. Sci. Rev. [3] Benkhoff et al., 2010, Plan. Sp. Sci. [4] Rothery et al., 2020, Sp. Sci. Rev.

Introduction: The physical properties of a particulate surface, like roughness, grain size, shape and transparency affect how it reflects the incoming light. This concept is used in planetary photometry to infer the surface properties of a celestial object from multiple observations taken from different directions and solar illumination (Hapke et al. 2012). Models linking the observed surface brightness with parameters related to physical properties of the surface have been established. The estimation of such parameters is referred as photometric modelling (Domingue et al., 2016). On Mercury, this technique has been employed to construct monochrome and color global mosaics, but it was never applied to investigate local surface features (Domingue et al., 2016). Therefore, the photometric modelling of Mercury’s surface features represents a novel and useful tool to investigate their nature. In addition, the identification of high-performance photometric models of any given surface material over multiple wavelengths enables to accurately predict the amount of reflected sunlight that will be observed through remote cameras and spectrometers. In this abstract, we first describe our modelling approach, discuss its improvement with respect to current available photometric models of Mercury, and present a few science cases in which it has been applied. Then, we will also show how this methodology is being applied for the calibration of SIMBIO-SYS observations that will be acquired during the Mercury Orbit Insertion (MOI) phase of the mission. Methodology: we first analyze the Tyagaraja and Canova craters hollows (i.e., tens meters to several km-sized shallow, irregular, flat‐floored depressions characterized by bright interiors and haloes, Blewett et al., 2011), which are covered by multiple overlapping 8 filter MDIS/WAC (Hawkins et al., 2007) images with resolution higher than 665 m/px and phase angles from 30° to > 100°. Over this region, we construct a latitude-longitude sampling grid with 665 m spacing. For each point we retrieve the surface reflectance and the solar illumination and observation angles using the 3D information of the global USGS DTM and the spacecraft and Sun position information within the observation SPICE kernels. This dataset is fitted with the Hapke and Kaasalainen-Shkuratov photometric models and estimates of their parameter are obtained for each point of the grid (see for example Fig 1C). Results Modelling performance: Our results suggest that photometric models derived from the inversion of multiple, overlapping observations are more accurate, especially for bright targets, rather than global photometric models of Mercury (Fig 1A,B). Overall, we estimate a modelling accuracy of better than 10% at 3σ, comparable with the radiometric noise level of the observations. Hollows results: Our results suggest that hollows are more backscattering than the floor of the crater in which they form. This is consistent with hollows being made of a material rich in holes and/or vescicles, in agreement with a formation by devolatilization. In addition, we find that they are smoother than the crater floor, consistently with the emplacement of a fine particles halo during hollow growth. Figure 1. Modeled vs Observed reflectance obtained with our KS3 model (gold) and the global one for Mercury for Canova (A) and Tyagaraja (B) craters. C) Example of Hapke single scattering albedo map of Tyagaraja crater. D) MOI SIMBIO-SYS footprints and the Regions of Interests (ROI) that are being analyzed for the cross-calibration of the three channels. Cross calibration of the SIMBIO-SYS channels: SIMBIO-SYS is a suite of three instruments, a high-resolution imager (HRIC), a stereocamera (STC) and a spectrometer (VIHI). Because of the dual-spacecraft configuration of BepiColombo, standard star observations with SIMBIO-SYS are not feasible until the satellite will be in its nominal orbit around Mercury. It is therefore pivotal to identify regions on the surface of Mercury with well-defined spectrophotometric properties that can be used as ground truth for the initial cross calibration of the three channels, prior to standard stars observations. Such regions will be also used to verify the integration times before the planning of the Global Mapping phase and to characterize the instrument straylight and pixel response non uniformity. The ROI will be observed during the Mercury Orbit Insertion (MOI) orbits where no standard stars pointing are still allowed. Therefore, we applied our methodology to identify ROIs within these orbits that currently have at least 5 MDIS/WAC observations, phase angles > 110° and resolutions higher than 665 m/px (Fig 1D). The retrieved photometric models for these regions will be used to determine accurate spectra (at the MDIS/WAC wavelengths) that will be interpolated within the SIMBIO-SYS photometric system and used to cross-calibrate the three channels of the instrument. Discussion Our analysis shows that overlapping multiangular MDIS/WAC observations can be used to invert local photometric models of the surface. This approach allowed us to initially study and characterize the scattering properties of hollows, finding that they are smoother and more back-scattering than the crater floors. This is consistent with hollows being formed by a volatile-release mechanism and emplacement of a halo of fine particles. We also found that this modelling approach is more accurate, in particular for high reflectance, than current global photometric models of Mercury. This led us to apply our methodology to selected locations that will be observed by SIMBIO-SYS during the MOI phase, and that will be used for absolute calibration of its three channels. More details will be presented at the conference. Acknowledgments and Data We gratefully acknowledge funding from the Italian Space Agency (ASI) under ASI-INAF agreement 2017- 47-H.0.

Lunar Gravitational-wave Antenna (LGWA) proposes to deploy an array of high-end seismometers on the surface of the Moon. The LGWA network will measure the lunar surface displacement excited by Gravitational waves (GWs) with a targeted observation band of 1mHz – few Hz. Seismic noise in that frequency band is very low due to the absence of atmosphere and oceans, representing the main inherent advantage that makes the Moon an ideal target for a GW detection experiment. The scientific and technical challenges of LGWA are diverse. Since its initiation, LGWA has relied on experts from fundamental physics, astrophysics, geophysics, engineering, and planetary science. The collaboration is currently organized in working groups (WGs) to cover five key themes: GW science, lunar science, payload, deployment, and operations. At the beginning of 2022, we started the activities of WG2 to assess the current knowledge of the lunar environment. We aim to characterize and develop models of deployment scenarios suitable for LGWA sensors, via a multi-pronged approach of data analysis and on-field experiments probing terrestrial analogs of lunar terrains. Besides characterizing the lunar seismic background noise, other goals of the group are related to modeling the lunar interior structure as well as Moon’s normal modes. These will be further used to develop a model of the interaction between the Moon and GWs. The knowledge about the displacement level of this excitation and the background noise will be used to define novel techniques for background noise reduction.For this purpose, WG2 is composed of physicists, engineers, geophysicists, and geologists. For our activities, we chose an interdisciplinary approach that requires initial communication efforts to create a common ground that will evolve into a crucial baseline activity for the whole LGWA project.Here we will report our progress in the first months of the activity of our collaboration.

The surface of Ganymede, which is the biggest satellite of Jupiter, shows strong tectonic deformation affecting both its geologic units, i.e., the younger light terrain and the older dark terrain. The dark terrain is characterized by low albedo, high crater density and furrows, which are morphotectonic structures formed by brittle deformation. Furrows are straight to curved fragments of troughs, with high albedo rims that bound a low albedo floor. Two systems have been recognized at the regional scale, which are the Lakhmu Fossae, whose furrow setting follows a concentric pattern resulting from a multi-ring impact basin, and the Zu Fossae, which follows a radial setting. In addition, local scale structures have been identified superimposed on the regional scale systems, leading to the reworking of the pristine structures. In this contribution, we investigate the tectonic evolution of the furrows in Galileo Regio (approximately from 180°-120° W to 0°-60° N), at both regional and local scale, with the identification of the tectonic events responsible for the deformation of this dark terrain. We performed a structural mapping and geostatistical analyses of the attributes of the mapped structures, such as the length, sinuosity, azimuth, spacing within the adjacent structures. Their quantification allows us to recognize a total of four structural systems within the area and to unravel the paleo-stress fields that have originated them. We prepared an evolutionary tectonic model of the furrow systems of Galileo Regio that shows the dynamics and the induced kinematics. We suggest that Galileo Regio underwent a sequence of tectonic phases associated with extensional and strike-slip regimes, these latter consistent with the kinematics that affected the light terrain of the adjacent Uruk Sulcus. This work advances the assumption that the dark terrain has been later affected by the same tectonics that deformed the light terrain and confirms the rejuvenation of the dark terrain towards a possible future transformation into light ones. The obtained results will be used for the scientific preparation of dedicated high-resolution observations that will be taken with the JANUS instrument onboard JUICE mission.Acknowledgments: The activity has been realized under the ASI-INAF contract 2018-25-HH.0.

The surface of Ganymede, the largest satellite of Jupiter, consists of a strongly deformed and tectonized brittle icy crust which stands on top of a large liquid body, possibly a global subsurface ocean. In fact, by means of multiple Galileo orbital mission flybys both geophysical and structural geology measurements constrained the average icy shell thickness to be comprised between 100 and 150 km. The surface can also be divided into two main units: bright and dark terrains depending on their relative albedo, impact crated density and tectonization. Furrows and grooves represent most of the structures on Ganymede’s surface, which are essentially extensional faults, dilatant structures and strike slip faults. We hereby present a 3D geologic modelling of the region of Uruk Sulcus based on structural mapping (Rossi et al., 2020) and using techniques borrowed from oil and gas exploration.The Uruk Sulcus area is a NW-SE bright terrain of ~400 km by ~2500 km size located between 150W-180W and 30N-10S, and characterized by pervasive sets of parallel/sub-parallel grooves of 10s-to-100s km length. The most favored hypotheses relate its formation either to a purely extensional context forming a tilt-block normal faulting, or to crustal necking with creation of horsts and grabens, or to be the result of a major dextral transpression. The overall structural framework and the fault geometries (in the form of 3D meshes) was created according to existing literature and with geologic interpretation and anchored on the surface to the global DEM by Zubarev et al., (2017), and at depth to the brittle ice-subsurface ocean interface to an average value of 120 km. This ice thickness value was obtained, among other methods, also by analyzing the scaling laws ruling the spatial distribution and the length size distribution of grooves and extensional structures, which proved to be fractal. One of the implications of this fractal behavior is that the structures themselves can be interconnected forming a percolating network favoring fluid circulation and connecting the subsurface ocean with the surface (see Lucchetti et al., 2020 and references therein).By means of 3D modelling, we were able to isolate volumes of ice encompassed by major strike-slip structures of Uruk Sulcus and to exploit the scaling laws ruling the structures within such areas, in order to numerically simulate a DFN (digital fracture network) crosscutting the entire volume of ice.This way we could analyze the volume of ice crosscut by such fracture network, and to predict the locations at surface where percolation is favored. Acknowledgments: The activity has been realized under the ASI-INAF contract 2018-25-HH.0.

Alpine peatlands occur in alpine, sub-alpine and mountain regions of the world and can be frequently found on the Alps as well as on the Andes, on the Tibetan Plateau, on the Australian Alps and in other regions of the world. Italian Alps host a large number of relatively small bogs and fens that can be found on gently sloping surfaces or in small valleys created by past glaciers. The high precipitation-low temperature climatic regime ensures large water availability to these ecosystems. The uniqueness and importance of peatlands in the Alpine territory is strongly linked to the countless ecosystem services that they provide, including their ability of sequestering and stocking carbon, providing habitat for flora and fauna including endangered species, supporting important biological diversity, being reservoir of high-quality freshwater during warm and dry seasons, and having the role of paleo-climate archives.Despite their importance, the peatlands of the Alps are still poorly studied and incompletely mapped, probably because they are relatively small and difficult to access. The use of remote sensing techniques provides a possible solution, allowing extending local measurements to wider areas in a fast and cost-effective way. Our hypothesis is that the spatial distribution of different plant associations as well as the spatial variability of vegetation biomass may provide important information for mapping the spatial distribution of peat properties, thus making remote sensing an effective method for peatland studies.In this work, we present the results obtained by using data collected by Unmanned Aerial Vehicles (UAVs) on the Val di Ciampo alpine peatland (Province of Belluno, northeast Italy) in July 2021. LiDAR data, hyperspectral data and aerial digital photos were simultaneously collected on an area of 88.000 m2. Field observations and measurements were performed in the same period, providing georeferenced ground information on vegetation and peat characteristics. Peat and vegetation samples were collected and analyzed in the lab. For each vegetation association we measured the height of plants and determined their above- and below-ground biomass based on 20 above-ground and 15 below-ground samples. As for the peat, we measured the peat thickness and determined the bulk density and the organic carbon content of 46 samples.Our results show that some of the correlations found between the parameters that characterize different vegetation associations can be used to calibrate the data collected by UAVs and extend the results from point locations to the entire peatland. For example, we found that the aboveground biomass is significantly correlated (r = 0.81, p < 0.001) to the local average vegetation height, therefore both LiDAR data and the Digital Surface Model (DSM) extracted from the photos can be used to estimate and map the vegetation aboveground biomass. The correlation between the surface microtopography and the aboveground biomass will also be presented, as well as other correlations between vegetation patterns and peat depth and properties. The significance of combining UAVs multi-sensor data with field observations for the characterization of Alpine peatlands will be discussed.

Radon (222Rn) is a radioactive gas widely considered an indoor air pollutant due to its harmful effects on human health (WHO, 2009). The Geogenic Radon Potential (GRP) quantifies what “Earth delivers” in terms of radon and represents the most important contributor to Indoor Radon Concentrations (IRC) indicating the potential risk over an area (Bossew 2015). This is the special case of some municipalities in Pustertal/Pusteria Valley (Bozen/Bolzano, North-Eastern Italy) which display a high IRC, based on Indoor measurements carried out by Minach et al. (1999), exceeding the threshold value recommended by EURATOM 59/2013. These municipalities are located along a wide brittle-fracture zone between the Pusteria Line (PL, the eastern part of Periadriatic Lineament) and the Deffereggen-Anterselva-Valles (DAV) faults. This fractured zone may act as preferential pathway for radon transport and migration by carrier gases (mainly CO2 and CH4), strongly contributing to its geogenic component. A GRP map of the study area has been developed based on field measurements of radon, thoron (220Rn) and other soil gases (CO2, CH4, H2, O2, H2S) according to a sampling grid in an area of 6x10 km, and along three profiles crossing above mentioned fault lines in Terenten/Terento, Mühlen/Molini and Pfalzen/Falzes specific areas. The GRP map was constructed by using soil gas radon data and other proxy variables in a spatial regression model. Soil gas measurements have been supported by high-resolution gamma-ray spectrometry on 16 rock samples belonging to the main outcropping lithologies in the study area i.e. granite, orthogneiss, micaschist-paragneiss, phyllite. The preliminary radon map highlights a wide area of radon anomaly located to the North of the Periadriatic Lineament. The global trend of these radon anomalies follows the structural trend of the brittle fracture zone between PL and DAV faults and tends to close from the eastern part (Pfalzen/Falzes) toward the western part (Terenten/Terento) of the study area. In particular the easternmost sector of the map displays a wide north-south area of radon anomaly related to a wide brittle-fracture zone probably composed by a system of sub-parallel faults. The spatial distribution of radon anomalies confirms the key role played by the Pustertal/Pusteria fault system in the fluid degassing processes enhancing geogenic radon potential of the Pustertal/Pusteria Valley. Keywords: Natural Radioactivity, Geogenic Radon Potential, Indoor Radon, Periadriatic Lineament References:Bossew Peter. Mapping the Geogenic Radon Potential and Estimation of Radon Prone Areas in Germany. Radiation Emergency Medicine 2015 Vol. 4, No.2 13-20.Council Directive 2013/59/EURATOM. Basic safety standards for protection against the dangers arising from exposure to ionising radiation.Minach L., Verdi L., Marchesoni C., Amadori C. Radon in Südtirol. Environmental Protection Agency. 1999.WHO 2009. Zeeb H. and Shannoun F. (eds.) WHO handbook in Indoor Radon - a public health perspective. ISBN 978 92 4 1547672.

Ganymede’s dark terrain represents the older geologic unit of the satellite, subsequently crosscut by swaths belonging to the younger light terrain. Compared to the light terrain, the dark terrain shows low albedo, higher crater density and morphotectonic structures called furrows. These structures are radial or circumferential fragments of troughs bounded by high albedo rims and a low albedo floor, generally thought being the remnants of a multi-ring impact basin similar to the Valhalla or Asgard basins on Callisto [1, 2]. In particular, in Galileo Regio and Marius Regio, the furrow systems show a concentric pattern centered at around 20° S 180° W, which is the assumed location of the crater formed by an impactor of 50-150 km in radius [3, 4]. Many furrows have been preserved until the present day in their pristine form, while some of them have acted as zones of weakness re-used by subsequent tectonic deformation. For this reason, they show a more complex morphology and are likely considered as precursors of light grooved terrain formation. In this contribution, we perform a structural mapping at the regional scale of the furrows in Galileo Regio, identifying their hierarchy and tectonic setting originated by the regional scale kinematics. Our mapping reveals that transpression, already recognized in the adjacent Uruk Sulcus area [5], affects the dark terrain of Galileo Regio, too. We mapped the structures in Galileo Regio (Fig. 1) by considering their spatial distribution and crosscutting relationships. In addition, we mapped the local-scale fractures that have tectonically modified remnants of furrows by leaving a deformation zone with higher albedo with respect to the surrounding dark material. These fractures show geometries and features associated with the Riedel shear, and synthetic and antithetic structures that form in strike-slip regimes [6]. The NE-SW and NW-SE trending structures that crosscut the concentric furrow systems occur from Uruk Sulcus to approximately 60° N and have been recognized as conjugate (Fig. 2). Hence, the setting of the mapped furrows and their associated structures allows identifying the (paleo)stress field that has affected this dark terrain. We infer that Galileo Regio has been characterized by regional kinematics consistent with the right-lateral transpression that has affected Uruk Sulcus. It is possible to recognize a ≈ NE-SW trending maximum horizontal stress (σh max) responsible for a shortening associated with strike-slip in the area that extends from 180°-120° W to 0°-60° N. Therefore, we can assume that the dark terrain has been deformed by the same tectonic processes that have formed the light grooved terrain of Uruk Sulcus. This work confirms the key role that transpression has played in the leading hemisphere of Ganymede and the reactivation (and possibly the inversion) of the furrows in Galileo Regio, which have followed a deformation history beginning from an impact origin to a tectonic remodeling. Further geo-statistical analysis will be performed to support this reconstruction. Obtained results from this study will be used for the scientific preparation of dedicated high-resolution observations that will be taken with the JANUS instrument [7] onboard JUICE mission [8]. Acknowledgements: The activity has been realized under the ASI-INAF contract 2018-25-HH.0. References: [1] McKinnon, W.B., Melosh, H.J., 1980. Evolution of planetary lithospheres: evidence from multiringed structures on Ganymede and Callisto. Icarus 44 (2), 454–471. https://doi.org/10.1016/0019-1035(80)90037-8. [2] Prockter, L. M., Figueredo, P. H., Pappalardo, R. T., Head, J. W., & Collins, G. C. (2000). Geology and mapping of dark terrain on Ganymede and implications for grooved terrain formation. Journal of Geophysical Research: Planets, 105(E9), 22519-22540. [3] Prockter, L.M., Collins, G.C., Murchie, S.L., Schenk, P.M., Pappalardo, R.T., 2002. Ganymede furrow systems as strain markers: implications for evolution and resurfacing processes. In: 33rd Lunar and Planetary Science Conference, Abstract #1272. Lunar and Planetary Institute, Houston. [4] Hirata, N., Suetsugu, R., & Ohtsuki, K. (2020). A global system of furrows on Ganymede indicative of their creation in a single impact event. Icarus, 352, 113941. [5] Rossi, C., Cianfarra, P., Salvini, F., Mitri, G., Massé, M., 2018. Evidence of transpressional tectonics on the Uruk Sulcus region, Ganymede. Tectonophysics 749, 72–87. https://doi.org/10.1016/j.tecto.2018.10.026 [6] Fossen, H. (2010). Structural geology. Cambridge, UK: Cambridge University Press. [7] Palumbo, P. et al. 2014. JANUS: The Visible Camera Onboard the ESA JUICE Mission to the Jovian System. 45th LPSC Meeting. Abstract #2094. [8] Grasset, O., Dougherty, M. K., Coustenis, A., Bunce, E. J., Erd, C., Titov, D., et al. (2013). JUpiter ICy moons Explorer (JUICE): An ESA mission to orbit Ganymede and to characterise the Jupiter system. Planetary and Space Science, 78, 1–21.

The surface of Ganymede has first been observed by the Voyager missions in 1970’s highlighting the presence of a deeply tectonized environment. Galileo Mission in 1996 imaged the Jovian satellites also providing at high-resolution images at targeted places during its flybys. Ganymede's crust is mainly composed of a brittle ice overlying a subsurface ocean, whose depth was constrained to be ~100-150 km [1]. The surface of Ganymede can be subdivided into dark and bright terrains depending on their crater density, differences in albedo and surface morphology. The latter is driven mainly by tectonization, characterized by presence of furrows and grooves. These structures represent the brittle deformation of the icy shell. We focus on the bright terrain located in the region of Uruk sulcus, a NW-SE terrain ~400 km wide and ~2500 km long located between 150W -180W and 30N-10 S strongly deformed by sets of parallel/sub-parallel (often evenly-spaced) grooves both at a regional and local scale. The presence of such structures in light terrains is hypothesized to be determined by tilt-block normal faulting [2], by crustal necking similar to mid ocean ridges [3], or by major dextral transpression, as in the case of Uruk sulcus [4]. It has been demonstrated that such structures show a fractal spatial clustering, and represent a preferential pathway for fluid from the ~100-150 km-deep ocean [1]. We are testing different 3D geomodelling approaches hence deriving more information on both the volume of the fractured brittle ice crust and the most favored location of actual percolation. Nowadays 3D geomodelling is approaching the planetary geology framework, as testified by the outcomes of the PLANMAP Horizon 2020 project [5, 6, 7, 8, 9]. With information either derived from direct surface observations and measurements and/or also constrained by geologic interpretation, it is possible to derive a 3D geomodel of the subsurface that represents specific geologic properties or geometries. We built a preliminary Uruk sulcus model geometry using the global DEM [10] as an initial, low-resolution surface textured with the controlled global mosaic from DLR of Voyager 1, 2 and Galileo images at an average resolution of 359 m/pixel. This served as an upper surface boundary to project the structural mapping from Rossi et al., (2020) and also as an anchor point to reconstruct the major Uruk sulcus structures. As a lower model boundary, the icy crust is constrained at depth by the ocean-ice interface. We used the depth value calculated using the fractal clustering analysis in [1] related to Uruk sulcus. We were able to reconstruct a preliminary qualitative model of the fault geometries for GUS1 (Grooves of Uruk Sulcus 1) system deformation ([4] as a large-scale structural framework. As a first test we focused on a smaller region in the sigmoidal area named S2 and containing the GUS3 (see white square in figure 1b). We extracted a voxel-based volume of icy crust comprised between the surface, the lower ocean-ice interface bounded by the major fault lines delimiting GUS3. At this location a major set of high-angle extensional structures at NE-SW arranged in a right-stepping en-echelon geometry are present, together with other two lower in number grooves families with NW-SE and NS orientations. With this voxel-based volume and knowing the scaling laws of the size distributions of these feature and their azimuths, it is possible to simulate a DFN (Digital Fracture Network) for each of the fractures’ families (fig. 2a). With the DFN it is possible to infer possible high-connectivity locations in the fractured ice volumes and their location at the surface (figure 2b). Further quantitative analysis work on the DFN and the volume of ice will allow to simulate the movement along the major structures backwards and forward in time in order and to capture the strain in the ice volume by incorporating its rheological parameters, and also test the transpression vs necking approach. The 3D geomodelling approach appears as a promising tool not only for scientific analysis but also to identify interesting target of future JUICE observation, where resurfacing or deep fluid expulsions could be more favored. Figure 1: a) The structural map by[4] with the families of grooves (GUS). In b) the 3D geometric reconstruction of the larger GUS1 structures. This analysis is focused in the white box Figure 2: In a) the modelled DFN with the three families of major structures and in b) voxel-based volume showing areas at higher connectivity. Acknowledgements: The activity has been realized under the ASI-INAF contract 2018-25-HH.0. References: [3] Pizzi, A., Domenica, A.D., Komatsu, G., Cofano, A., Mitri, G., Bruzzone, L., 2017. Spreading vs. Rifting as modes of extensional tectonics on the globally expanded Ganymede. Icarus 288, 148–159. https://doi.org/10.1016/j.icarus.2017.01.034 [4] Rossi, C., Cianfarra, P., Salvini, F., Mitri, G., Massé, M., 2018. Evidence of transpressional tectonics on the Uruk Sulcus region, Ganymede. Tectonophysics 749, 72–87. https://doi.org/10.1016/j.tecto.2018.10.026 [1] Lucchetti, A., Rossi, C., Mazzarini, F., Pajola, M., Pozzobon, R., Massironi, M., Cremonese, G., 2021. Equatorial grooves distribution on Ganymede: Length and self-similar clustering analysis. Planetary and Space Science 195, 105140. https://doi.org/10.1016/j.pss.2020.105140 [2] Pappalardo, R.T., et al., 1998. Grooved Terrain on Ganymede: First Results from Galileo High-Resolution Imaging. Icarus 135, 276–302. https://doi.org/10.1006/icar.1998.5966 [7] Pozzobon, R., Penasa, L., De Toffoli, B., Rossi, A. P., & Massironi, M. (2020). 3D geo-models based on multiple datasets on Mars (implicit or explicit modelling) (Public D6.1; Planmap Deliverable). [8] Penasa, L., Pozzobon R., Rossi, A. P., Massironi, M., (2020), 3D geo-models based on multiple datasets on the Moon (implicit or explicit modelling) (Public D6.2; Planmap Deliverable). [9] Pozzobon, R., Penasa, L., Massironi, M., Ferrari, S., (2021) 3D geo-models based on multiple datasets on Mercury (explicit modelling) (Public D6.3; Planmap Deliverable). [6] Massironi, M., Rossi, A. P., and the PLANMAP Consortium, PLANMAP Final report 2021 [5] Massironi, M. et al., 2018. Towards integrated geological maps and 3D geo-models of planetary surfaces: the H2020 PLANetary MAPping project, in: EGU General Assembly Conference Abstracts, EGU General Assembly Conference Abstracts. p. 18106. [10] Zubarev, A., Nadezhdina, I., Brusnikin, E., Giese, B., Oberst, J., 2017. A search for Ganymede stereo images and 3D mapping opportunities. Planetary and Space Science 146, 40–54. https://doi.org/10.1016/j.pss.2017.07.021

Rembrandt is a 715 km-diameter basin on Mercury centered at 32.89°S latitude and 87.86°E longitude. This crater constitutes a remarkable example of the stratigraphic variability on Mercury. The uppermost smooth plains of volcanic origin, which are temporally unrelated to the impact event, have been distinguished by the surrounding smooth plains utilizing spectral information. The basin is crosscut by a prominent NE-SW thrust system more than 1000 km long, named Enterprise Rupes (Ferrari et al., 2015; Galluzzi et al., 2015; Semenzato et al., 2020), attributed mainly to crustal shortening induced by global contraction (see Semenzato et al., 2020 and references therein). This consists of a set of lobate scarps and wrinkle ridges with inverse to transpressional kinematics (Massironi et al., 2015). The aim of this work, as part of the PLANMAP Horizon 2020 project, is to use all the available information on the site to provide a comprehensive 3D model of both the structural setting and the thicknesses of the main units of the Rembrandt basin infilling using explicit modeling approach. The principle of three-dimensional explicit modelling relies on the creation of 3D surfaces based on geologic observations and constraints. While implicit modelling and its effectiveness rely on the amount of available data both on the surface and the subsurface to provide a mathematical solution that satisfies all the constraints, the explicit geological modelling implies a more extended geologic interpretation based on the available data which is subject to the operator’s experience and is essentially based on the construction of several interpreted cross-sections to be then interpolated generating mesh surfaces. The advantage is that such type of geologic modelling can be applied in areas with scarcity of data, especially related to subsurface constraints. In the case of the Rembrandt basin, we mainly based our reconstruction on the geo-stratigraphic map and geologic cross-section from Semenzato et al. (2020). Additional constraints, regarding fault kinematics and fault plane geometry, were provided by Galluzzi et al. (2015) and Crane (2020). As a basemap, we used the MESSENGER MDIS global mosaic at 166 m/pixel together with the MDIS global DEM (665 m/pixel), both of them available in the USGS repositories, with the same Lambert Conformal Conic (LCC) projection of the geo-stratigraphic map. In Rembrandt basin two different infillings - the YIP (Young Interior smooth Plains) and OIP (Older Interior smooth Plains) units - overlay the IT (para-autochtonous intracrater plains) base unit. The thickness of these units was estimated with several methods in Semenzato et al., (2020), among which the presence of impact craters excavating and exposing the inner basin stratigraphy. We used such craters for the construction of the interpreted cross-sections in complement to the one by Semenzato et al., (2020). These were subdivided into two intersecting sub-parallel sets. The interpreted subsurface horizons were used for mesh interpolation together with the geologic contacts between the different units on the surface creating meshes representin ghte top of the YIP, OIP and IT basin infilling units. The volume between them was then calculated. The structural modelling was carried out using the structural mapping from Semenzato et al., (2020) and Ferrari et al., (2015). The faults’ vergence and their angles were extracted both thanks to the illumination conditions on the image mosaic and topography, to the measurements provided by Galluzzi et al., (2015) on displaced impact craters and to the work by Crane (2020) and Massironi et al., (2015). This way we were able to model the Enterprise rupes thrust geometry, its splays and backthrusts as well as contractional lobate scarps and extensional radial features within the basin infilling units. Although requiring a certain degree of assumptions especially on planetary bodies, the 3D geomodelling proves to be a useful tool in order to check surface interpretations that might change once set into 3D environment and refine volume calculations and 3D shape of geologic units. Follow up investigations will focus on forward and backwards modeling work on the activity of the Enterprise Rupes system. Figure 1: in a) the mesh construction for the main Enterprise rupes structure, constrained with surface mapped lineaments and anchored on the geologic cross-section. In b) the tetrahedral volumetric mesh representing the two events of Rembrandt basin infilling. In c) the structural and stratigraphic geomodel of Rembrandt basin (https://skfb.ly/6ZqtI). Acknowlegements: This research was supported by the European Union’s Horizon 2020 under grant agreement No 776276‐PLANMAP. References: Crane, K., 2020. Structural interpretation of thrust fault-related landforms on Mercury using Earth analogue fault models. Geomorphology 369, 107366. https://doi.org/10.1016/j.geomorph.2020.107366 Ferrari, S., Massironi, M., Marchi, S., Byrne, P. K., Klimczak, C., Martellato, E., & Cremonese, G. (2015). Age relationships of the Rembrandt basin and Enterprise Rupes, Mercury. Geological Society, London, Special Publications, 401(1), 159–172. https://doi.org/10.1144/SP401.20 Galluzzi, V., Di Achille, G., Ferranti, L., Popa, C., & Palumbo, P. (2015). Faulted craters as indicators for thrust motions on Mercury. Geological Society, London, Special Publications, 401(1), 313–325. https://doi.org/10.1144/SP401.17 Massironi, M., Di Achille, G., Rothery, D. A., Galluzzi, V., Giacomini, L., Ferrari, S., Zusi, M., Cremonese, G., & Palumbo, P. (2015). Lateral ramps and strike-slip kinematics on Mercury. Geological Society, London, Special Publications, 401(1), 269–290. https://doi.org/10.1144/SP401.16 Semenzato, A., Massironi, M., Ferrari, S., Galluzzi, V., Rothery, D. A., Pegg, D. L., Pozzobon, R., & Marchi, S. (2020). An Integrated Geologic Map of the Rembrandt Basin, on Mercury, as a Starting Point for Stratigraphic Analysis. Remote Sensing, 12(19), 3213. https://doi.org/10.3390/rs12193213

Introduction: The Space Science Data Center (SSDC) developed MATISSE (Multi- purposed Advanced Tool for the Instruments for the Solar System Exploration, [1]) webtool, whose v2.0 update [2] is available at https://tools.ssdc.asi.it/Matisse/, which allows access to data of the planetary exploration missions. The MATISSE tool uses some protocols provided by the Virtual European Solar & Planetary Access (VESPA), including EPN-TAP, and allows access to a series of services without necessarily having to download the data, but view the maps directly online. In this context the work here presented points at improving and expanding the functionalities of the MATISSE tool to the planetary geology, by including some already published geological maps. These will be essential in order to make MATISSE a useful tool for the analysis of planetary surfaces. MATISSE for planetary geology: The geological maps involved in this project will be of fundamental help to the scientific community in the geological characterization of landing sites and to obtain useful information for the study of planetary bodies surface. The good choice of the landing site, which satisfies both engineering and scientific requirements, represents one of the key points for the success of a space mission. For example, the identification of landing sites, of particular geological / mineralogical interest, will be carried out thanks to data fusion techniques between visible images and infrared spectroscopic measurements. The tool in question will give the user the opportunity to observe the area in question integrating data of multiple sources. MATISSE will also be able to carry out geomorphological analysis and morphometric products (e.g. slopes, relief, roughness index) which will allow a complete investigation both from the geological and engineering point of view. The geological maps will be integrated with mineralogical maps, obtained using infrared spectroscopic data. In collaboration with PlanMap and GMap teams we are currently working to include Martian, Hermean and Cerean surfaces so that both recently ended missions (e.g., NASA’s Dawn) and missions still not in their scientific phase (e.g., ESA’s BepiColombo) would benefit for this work. Work methodology: The geological maps of interest will be downloaded in appropriate format, so that every polygon representing a geological unit can be separately inserted into the geospatial database of MATISSE and be easily retrieved by the user. In particular, the user can choose one or more of the polygonal units as input for the geographical query after selecting the target and the instruments of interest. In this way the MATISSE capabilities can be fully exploited even trough geological oriented requests. Here are some examples of areas that we have analyzed on the Martian surface, with the collaboration of the PLANMAP team. These sites, Firsoff Crater and Commelin Crater, are located in Arabia Terra region. After a careful geological analysis of the two craters, similar morphological characteristics were identified [3]. After starting the query, the user will see the area with the selected lithologies displayed (figure 1) and can carry out appropriate analyzes. Expected outcomes: We plan to make available the first release of MATISSE with geological maps in the next months, even if starting with only limited capabilities. The inclusion of these functionalities in the tool could produce a sensible step forward in the study of planetary geology, with the possibility of better exploiting different datasets and taking also into account the collaboration of different teams already leaders if this field. Another goal will be to expand the use of the tool, making it similar to the Geographic Information System (GIS). We will expand the possibility of selecting specific areas to be analyzed on the base of the geographical position of the data and the pertinence to specific geological units. It will be also possible to obtain topographic profile and select multiple data to be simultaneously observed. All these analyzes will be performed directly on 3D models. References: [1] Zinzi A. et al. (2016) Astron. Comput., 15, 16-28. [2] Zinzi A. et al. (2019) EPSC-DPS Joint Meeting 2019, id. EPSC-DPS2019-1272. [3] Pondrelli M. et al. (2010) Earth and Planetary Science Letters, 304, 511-519.

Introduction: The origin and formation of Hollows, puzzling surface features identified on MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging, [1]) images [2], represent one of the major open science questions about Mercury surface processes and landforms. Hollows are 10 m to several km-sized shallow, irregular, flat‐floored depressions characterized by bright interiors and haloes and found on crater walls, rims, floors, and central peaks [2,3]. Although a well-established framework explaining their nature and formation is still lacking, current hypotheses envision the release of volatiles from the surface of Mercury [1] through processes like sublimation, desorption, sputtering, micrometeorite impacts and pyroclastic volcanism. In this abstract, we analyze multi-angular Mercury Dual Imaging System (MDIS,[7]) wide angle camera (WAC) color images of hollows-hosting Canova (25.62°N, 3.75°W) and Tyagaraja craters (3.89 °N, 138.9°W), with the aim of investigating the spectrophotometric properties of these features. Methodology: We collected multiple MDIS/WAC images covering the hollows at Canova and Tjagaraya crater in 8 out of 11 filters ranging from 433 nm to 996 nm. Each image was processed with the ISIS software through the spiceinit and mdiscal and cam2map commands and downsampled to 665 m/px. The phocube task was used to compute the local incidence, emission, phase and solar and spacecraft azimuth. Next, a sampling grid with a scale of 665 m was constructed (Fig. 1A). For all observations in each filter, the flux and the photometric angles are collected at each sampling point (Fig. 1A, 1B). This data was fitted with a basic Hapke model and different version of the Kasalaainen-Shkuratov models (KS1 to KS6 as defined in [8]). The fitted parameters were used to correct each observation to the standard illumination and observation geometry (i.e., incidence=30° and emission=0°) and average all the images in each band to obtain spectra at a higher SNR than those based on a single image of the same resolution. Figure 1 A) Sketch of the MDIS/WAC Canova dataset. B) WAC G-band image coverage (violet, in transparency. C) Area under investigation (pink square). D) Boxplots of the ratio between the observed and predicted flux for each fitted model. Results and discussion: The performance of our correction is shown by the box-plots in Fig. 1D. On the y-axis we report the ratio of the observed vs predicted flux for the I (996.2 nm) band. We plot only 1 band for clarity, but the others give similar results. The fitted photometric models allow to reproduce the observed flux values with an error below 10% at 3σ, which is comparable with the radiometric accuracy of the MDIS/WAC datasets. Figure 2 A) MDIS/NAC global mosaic of Mercury showing Canova crater. The blue and brown areas represent the Canova hollows (CA HOL). And crater floor material (CA CF) ROIs, respectively. B) MDIS/WAC image of Tyagaraja crater. Lightblue and gold areas are the Tyagaraja hollow (TY HOL) and crater floor material (TY CF) ROIs, respectively. Figure 3 Continuum removed reflectance spectra of Canova and Tyagaraya hollows (CA HOL, TY HOL) and crater floor material (CA CF, TY CF). Continuum removed reflectance spectra of the hollows and crater floor materials (“CA HOL” and “CA CF” ROIs in Fig. 2A for Canova ,“TY HOL” and TY CF” ROIs in Fig. 2B for Tyagaraja) were extracted from the average of all the corrected images in each band and are shown in Fig. 3. Consistently with the multi-band, MDIS/WAC, clustering-derived spectra from [5], our hollows spectra show an absorption between 600 and 800 nm. From the same ROIs we also extracted the best-fit parameters for all the photometric models. The distribution of the Hapke single-scattering albedo for the hollows and the crater floor material is shown in Fig. 3. In particular, hollows have a higher single-scattering albedo and a more spread distribution than the crater floor material. Interestingly, the hollows distributions are very similar for both craters. Figure 4 Single scattering albedo (w) parameter for the Canova and Tygaraja Hollows (light-blue and blue histgorams) and crater floor materials (brown and gold histograms) in the MDIS/WAC filters. Conclusions We analyzed MDIS-WAC images in 8 out of the 11 WAC filters showing hollows on the floor of Canova and Tyagaraja craters on Mercury. These observations were used to fit several photometric models, allowing to standardize all images and obtain high SNR spectra of hollows and the crater floor material. Consistently with previous works, hollows are characterized by an absorption between 600 and 800 nm. In addition, we are investigating the model parameters for both materials in each band. This preliminary investigation already shows that hollows have a higher and more spread single-scattering albedo distribution than the crater floor material. In addition, the single-scattering albedo distributions of hollows at Canova and Tjagaraya are very similar. This spectrophotometric characterization will be useful to further investigate these features with high-resolution DTMs, color images and spectra from the SIMBIO-SYS [9] instrument onboard BepiColombo. A more in depth spectroscopic and photometric analysis, covering all the Hapke parameters and the considered photometric models will be presented at the conference. Acknowledgements: This study is supported by the BepiColombo ASI-INAF contract n° 2017-47-H.0. References: [1] Solomon, S.C., et al., 2007, Space Sci. Rev. Space Sci Rev 131, 3–39, [2] Blewett, D.T. et al, 2011. Science,80; [3] Blewett, D.T. et al., 2013 JGR:Planets,121,9,1798-1813; [4] Vilas, F., et al. 2016, GRL ,43,4, 1450-1456,[5] Lucchetti, A. et al., 2018. JGR:Planets, 123-9,2365-2379, [6] Pajola, M. et al, 2020, PSS, 105136, [7] Hawkins, S.E. et al., 2007. Space Sci Rev 131, 247–338 [9] Domingue, D. et al. 2016, Icarus, 268, 172-203 [9] Cremonese G. et al., 2020. Space Sci Rev 216, 75

The volcanic provinces are embedded between the NE margin of b56 /Lennon-Picasso basin and high terrain bounding structures. Resulting plains are interested by endogenic pits associated with pyroclastic activity, in agreement with the observation that Mercury's explosive volcanic vents tend to be located along major fold and thrust belts (Byrne et al 2014) and around large impact basins. Recent large scale mapping defined them intercrater plains partly covered by smooth plains (Malliband et al 2019; Whitten et al 2020). In addition to endogenic pits, these provinces display several 10-km diameter prominent cones, sometimes aligned forming high-relief ridges, resembling constructional edifices. In colour composite images, cone tops are peculiarly darker (blue) or, alternatively, brighter (and yellow) with respect to the surrounding material. On the surface Mercury, Wright et al. (2019) interpreted two randomly located constructional edifices of similar size, attributing their origin to a late highly viscous stage of volcanism that followed lower-viscous stage that are thought to provide typical smooth plains. Wider et al. (2016) proposed that the encounter of highly-viscous lavas with C-rich material during the magma ascent can easily provide volatiles (Zolotov et al. 2011) that progressively accumulate and lead to explosive eruptions. The resulting high reflectance of pyroclastic deposits would arise from removal of graphite as it was consumed during oxidation. The study aims to reveal the nature of cones at the margin of the Lennon-Picasso basin and to explain the relationship between a potential long-lasting volcanic activity and the concurrent global contractional regime.Authors received funding from the Italian Space Agency (ASI) under ASI-INAF agreement 2017-47 and from European Union’s Horizon 2020 research grant under agreement 776276- PLANMAP.

The Geologic Mapping of Planetary Bodies (GMAP) project Integrates partners and outputs from two projects previously funded by the EU through Horizon 2020 (UPWARDS and PLANMAP) to deliver tools and services for geological mapping of any Solar System body. Started in 2020, GMAP is developing an infrastructure to support future European missions in developing orbital acquisition strategies, rover deployment and traverses, and human exploration programs. Part of GMAP deals with the study of current procedures for publishing planetary maps, and the development of new ones. Since the Apollo era, geologic maps of the Moon and bodies of the solar system have been produced and disseminated by the United Stated Geologic Survey, Astrogeology Program, funded by NASA. Being both USGS and NASA governmental organization of the same country, the coordination and the production of planetary maps followed a straightforward development from the beginning to the digital-era. In their digital form, the US maps have been made available under the public domain.At the international level, every country has its own space agency or office but no public domain planetary maps have been systematically made available yet in re-usable formats outside the US. In Europe, space programs can be either promoted by European Space Agency or by any one of the participating states' space agencies, which is not necessarily an EU member. This is not ideal for a coordinated work for geoscientific mapping or dissemination of unified planetary mapping products.Within GMAP we are surveying existing licensing models, looking for a licensing system that guarantees dissemination and the re-use of planetary mapping, the maximum compatibility with the existing dataset and protects original creator rights. We will report the status of our study and plans for the future.

In the early 90’s, the Environmental Protection Agency of the Bolzano Province (NE Italy) performed a study on Indoor Radon in all the municipalities of the district (Minach et al., 1999). The aim of these measurements was to identify the areas characterized by high Indoor Radon (IR) values to realize an Indoor Radon map. Most of the municipalities that resulted to have average IR values above 400 Bq/m3, thus classified at high risk according to 90/143/EURATOM, are aligned along the Pustertal/Pusteria Valley. In this work, the relation between Radon activity, and the concentrations of other gases in the soil, and geological factors (e.g. lithology, tectonic structures) is investigated along two profiles across the Periadriatic Lineament in the Pustertal/Pusteria Valley. Samples of the petro-volumetrically relevant lithologies of the studied area have been collected, their chemical composition (XRF) and their radionuclides content (high resolution gamma-rays spectrometry) determined. The lithologies include granitoid rocks, orthogneisses, micaschists and phyllites, some of which are characterized by a high activity concentration of natural terrestrial radionuclides. As a consequence, their presence in the study area may potentially increase Radon emission (EC-JRC, 2019). Radon, CO2, CH4, O2, H2 and H2S have been measured in soil gas along the two profiles to investigate the effect of the Periadriatic Lineament (PL) on Radon exhalation. The profiles are located near Mühlen/Molini (P1) and Pfalzen/Falzen (P2), respectively. Preliminary results show two evident Radon peaks of 112 kBq/m3 and118 kBq/m3 along P1, and of 148 kBq/m3 and 157 kBq/m3 along P2. The background values are below 50 kBq/m3. These peaks correspond to two main cataclastic zones of the Periadriatic Fault system mostly buried under quaternary loosen sediments. Thus, cataclastic zones represent preferential paths for Radon mobility and exhalation. The comparison of the IR distribution map, the geochemical composition of the main lithologies and the results from the in-situ measures, clearly indicate that, although outcropping lithologies represent an important factor contributing to the IR values, they cannot justify such high IR values measured in the buildings alone. Instead, the structural features of the Periadriatic Fault system play a key role in enhancing radon exhalation, exposing to potential radon risk specific areas within the territories of the municipalities located in the Pustertal/Pusteria Valley.Keywords: Eastern Alps, Periadriatic Lineament, Radon, Indoor Radon, Natural RadioactivityReferences:Minach L., Verdi L., Marchesoni C., Amadori C. Radon in Sϋdtirol. Environmental Protection Agency. 1999.Cinelli G., De Cort M. & Tollefsen, T. European Commission, Joint Research Centre. European Atlas of Natural Radiation. 2019. (Eds.), Publication Office of the European Union, ISBN 978-92-76-08259-0, doi:10.2760/520053.

Among the variety of earth analogues, what surely stand out are lava tubes. A lava tube is a type of lava cave formed by a low-viscosity lava flow that can develop 1) forming a continuous and hard crust, which forms a roof above the still flowing lava stream (over-crusting), or 2) slipping between pre-existing lava flows (inflation). The resulting structure constitutes among the most efficient thermal structures on Earth, because of their capacity of thermal insulation isolated lava flows can travel over long distances across lava fields. Lava tubes, which on Earth are typical features of lava fields encountered in intracontinental plateaus and volcanic-shield islands (slopes Indeed, in the last decade, high-resolution orbital images on planetary bodies like Mars and the Moon offer the possibility of studying the morphology of these structures, detecting them from the recurrent collapses in the pyroduct’s roof, that shows the presence and the path of the pyroduct itself. The pit chains show characteristics similar to those on Earth: elongated with minor axis representing the width of the tube and with major axis along the flow direction. The differences in gravity between Earth and the other planetary bodies and its concurrent influence on the effusion rates result in a significant difference in lava tube dimensions, indeed, terrestrial pyroducts tend to generally have a smaller width (10–30 m) than those on Mars (250–400 m) and the Moon (500–1100 m) [3]. In the post-cooling phases, lava tubes are characterized by a near-constant inner temperature and, on other planetary bodies, they might offer natural protection against micrometeorites and solar and cosmic radiations making them ideal locations for future planetary explorations. Within this framework, studying the largest lava tubes on Earth is of interest as they could represent the best planetary analogues. In order to employ lava tubes as locations for future explorations, it is important to understand exactly how they form and develop not only during the active phase (flow-phase) but also and more importantly during the post-cooling phase. Alongside the NW African continental margin (Morocco), is located the Canary Island Seamount Province (CISP), a magmatic province generated by the extremely slow transit (~8–10 mm/yr) of the African plate over a hotspot during more than the last 133 Ma [5] and hence represents both long-term and spatially focused volcanic activity over a poorly mobile tectonic plate. For this reason, it constitutes one of the best terrestrial analogues of the Martian one-shell plate volcanism [6]. In the NE region of Lanzarote (Canary Islands) stands La Corona lava tube system that, with its 7.6 km length and an average width of 30 m [4], is one of the largest volcanic cave complexes on Earth. Therefore, the occurrence of volcanism on an almost stationary plate and the impressive dimensions of La Corona lava tube make it one of the most suitable lava tubes for interplanetary analogies. Different field surveys were conducted over the last two years in order to explore its three-dimensional geometry using 3D laser-scan. These data allowed to place constraints on the tube origin (inflation process rather than over-crusting), the involvement of thermal erosional processes (inferred from characteristic morphologies) and to identify a weak pyroclastic level within the tube which might have favoured the inflated tube inception. Also, the presence of an important amount of secondary mineralisation inside the tube has been very significant in understanding the evolution of the pyroduct in the cooling and post-cooling phases. These secondary mineralisation (mainly sulphates) show an interesting contribution from the Aeolian and marine environment in the latest evolutionary stages of this lava tube. Studying this exceptional example of terrestrial lava tube will allow to improve our understanding of the formation and evolutional processes giving rise to analogue features on other planetary bodies of the Solar System. [1] Haruyama, J. et al. (2012) Trans. JAPAN Soc. Aeronaut. Sp. Sci. Aerosp. Technol. JAPAN 10 [2] Tettamanti C. (2019) Analysis of skylights and lava tubes on Mars, Department of Physics and Astronomy “Galileo Galilei", Univerisy of Padova (Italy) [3] Sauro, F., et al. (2018) 49th Lunar Planet. Sci. Conf. 2018 [4] Carracedo, J. C. et al. (2003) Estud. Geol. 59 [5] van den Bogaard, P. (2013). Sci. Rep. 3 [6] Meyzen, C. M., et al. (2015) Geol. Soc. London, Spec. Publ. 401

A bifocal panoramic stereoscopic camera (BIPS) has been designed a realized as a terrestrial prototype. The core of the camera is a novel Bifocal Panoramic Lens (BPL) we designed and realized, which is able to carry out a panoramic field of 360° in azimuth, 100° in elevation (+60°/-40° with respect to the horizon) and, simultaneously, an enlargement of a part of the panoramic field. All of that using an unique image sensor and avoiding any moving part. BIPS consists of a twin couple of BPLs settled in an appropriate stereoscopic baseline. It allows the monitoring of the surrounding environment in stereoscopic (3D) mode and, simultaneously, to capture a higher resolution stereoscopic images to analyze scientific cases. If mounted on a planetary rover, BIPS merge engineering stereoscopic capabilities for autonomous driving with an optical stereoscopic channel for scientific purpose, making it a new paradigm in the planetary rovers' framework. The operational aims include the identification of boulders, crevasses and other surfaces that can be obstacles for rover trafficability, in addition to the 3D reconstruction of exploration sites for improving situation awareness during both roving and human operations. On the other hand, the correct and detailed 3D reconstruction of exploring sites allows detailed measurements of many geological features such as: sedimentary structures (strata attitudes, geometry and thickness); fracturing networks (attitudes and persistence); folds and faults systems (orientation, vergence and displacement); veining systems (frequency, orientation and thickness); mounds, vents and ridges (slope and aspect); boulders (size frequency distribution). All these measurements are pivotal for the understanding of tectonic, sedimentologic, volcanic, erosive, fluid-rock interaction and impact processes on planetary surfaces. In this paper we describe the optical characteristics of a BPL, the realized terrestrial BIPS, the stereoscopic calibration and some possible scientific cases within the lunar exploration framework.

Pit chains commonly occur along a bounding fault, allowing to infer a genetic relationship between grabens and pits. In this work we propose a comprehensive model for the formation of pit chains , the complex sequence of rift system and troughs in Noctis Labyrinthus. Like other previous authors, we confirm that a volcano-tectonic activity is the main process controlling the generation of such interesting and intricate structures in the studied area. We analyzed the geometrical properties and the maximum displacement as a function of fault length and cumulative frequency of fault length distribution for 499 mapped faults, which reveal the host lithology of the faults and the arrangement of rocks in of the crust and the lithosphere. We finally suggest a model where a relative sequence of events responsible for the formation and development of the scalloped network of troughs in Noctis Labyrinthus (Mège et al.,2003).In this model, the magma propagates from depth to the surface by exploiting a network of interconnected fractures, and as a consequence, this magma inflation generates the formation of dike-induced grabens and pit chain on the surface. Introduction Noctis Labyrinthus is one of the enigmatic area in the surface of Mars.This area is made up by a complex inter-connected network of canyons and branched extensional faults and grabens Fig.1.These particular features of unknown origin, make Noctis Labyrinthus an interesting target to understand the possible factors that control the formation of these complex grid of troughs and infer the possible fault system evolution. We performed a detailed qualitative and quantitative study of these faults system through the study of their geometrical properties and surface morphology in order to understand their mechanical evolution and variations over different scales of length, the mechanisms of growth and the related stress field. We measured the maximum displacement as a function of faults length. The Dmax/L diagram provides slightly different results according to the fault type, since this ratio change from normal, thrust, and strike slip faults, so it provides information about the possible nature of the faults in the selected area (Seog Kim et al., 2005). The cumulative frequency plot Fig.3 was used to infer the scaling law of the fault system and faults growth, determine the lithology of the faulted rocks, the arrangement of materials in the subsurface and also the vertical confinement of faults vs. penetration of the brittle crust (Sornette.,2009; Torabi and Berg., 2011;Sornette et al., 1993; Cowie et al., 1991). Fig.1.Surface interconnection between faults and pit chains, which follow a linear trend. Faults sizes and colors are labeled on the graph. 1. Data and methods In our work, as a basemap, we used two orthoimages H3210_0000 and H3221_0000 from High Resolution Stereo Camera (HRSC) on board Mars Express, bearing a resolution of 12.5 m/pixel and for the surface topography, we utilized an individual Digital Elevation Model (DEM) from Mars Orbiter Laser Altimeter (MOLA) on board Mars Global Surveyor, with resolution of ~460 m/pixel. With these data sets, we made all morphometric measurements required for characterizing the faults and the grabens systems, analyzing faults distribution using rose diagrams, measuring faults lengths and the maximum vertical displacement of faults population and carry out a DMax Vs. L diagram and a cumulative frequency plot by input data in Origin software. Afterward, we studied the relationship of those fractures in terms of the formation and evolution of Pit chains and troughs. 2. Discussion and Conclusion Noctis Labyrinhus is a framework of intricate rifts systems and branched faults, that have coalesced together to form an interconnected topography characterized by large troughs and canyons, driven by an invariant extensional stress field. Fault grow and develop at the same way but at different scales (Schultz et al., 2000; Turabi and Berg., 2011). Crustal-Scale linkage in localized faulting zone is responsible for the formation of rift segment border by a pre-existing fracture (Soliva and Schultz., 2008). So far, only a few locations on Mars, where the DMax/L relationship has been measured. In our work, the nonlinear distribution in the Fig.2 might be explained by the presence of small size fractures, with different depths, which could be one of reasons that affect the large distribution of measurements in the Displacement-Length diagram (Turabi and Berg., 2011), or alternatively, it could be linked to the brittle crust thickness that control the displacement and the length of faults as in the terrestrial analogues faults systems (Soliva and Schultz., 2008; Schultz and Fossen.,2002; Soliva et al., 2005; Comie., 1998). Fig.2. DMax /L diagram of faults studied in this work, shows a large scattering of values. The different DMax /L limits are plotted in various lines with different colors. Topographic offsets was measured along single MOLA tracks. The cumulative frequency Vs. Length of fault population values grows in exponential fit Fig.3 of size distribution, mainly reflecting the presence of layered sequence of massive basalt (R.Soliva and R.Schultz., 2008). Fig.3.The cumulative size distribution of the fault length population with Exponential and Power Law fits. On the diagram, the Exponential function fits the most with the main trend. Furthermore,We classified pit chains as a morphological features of volcanic collapse generated by pressure drop above dikes (Mège and Masson., 1996; Liu and wilson., 1998; Scott et al., 2000; Mège and Masson., 1996; Wilson and Head., 2002; Ernst et al., 2001; Mège et al.,2003).Dikes play an important role to connect the surface to the magmatic source. The magma chamber at depth continuously generate flow that will be transported later to the upper levels through the dikes (Mège et al.,2003). This procedure will produce a stress in the dike tip, followed by deflation causing the collapsing of the surface, where there is a graben already formed. This sequence of events is responsible for the generation of the pit chain.We are suggesting a model based on a coupled physical processes of an early extension, visible on the surface by a forked grid of faults and grabens and a magma plumbing. Acknowledgements This research has been supported by European Union’s Horizon 2020 under grant agreement N° 776276-PLANMAP.

Introduction Grooves represent the evidence of tectonic activity that deformed Ganymede surface during its geologic evolution and may have played a key role in the possible connection between surface and the subsurface ocean. In this context, the analysis of Ganymede deformed surface could provide hints regarding its interior, as well as its ice shell’s mechanical behaviour. Indeed, faults distribution and fault populations on icy satellites can reveal insights into the evolution of their surface that cannot be gained with other techniques. In particular, statistical characterization of fault-population attributes, such as length and clustering, are fundamental means to explore deformation rates, stress transmission modes, rheology of the medium, and mechanical layering [1,2,3,4,5]. The fractal analysis has been used in terrestrial planets studies to determine the thickness of the fractured crust [e.g., 6,7,8]. In the same fashion, on icy satellites the exploration of the depth at which fractures penetrate the icy layer could be constrained investigating the main characteristics of fault populations, such as length size-distribution and clustering [9]. In this work, we analyse the grooves’ length and spatial distribution to estimate the potential thickness of the icy crust above the deep ocean required to develop densely populated structures at the surface of Ganymede (i.e. the grooves). Dataset and Methods Our analysis is based on the regional scale grooves mapping [10] that represents a useful dataset to improve the knowledge of the tectonic evolution of the satellite and to recognize the main characteristics of these features. Thanks to these comprehensive grooves mapping dataset, we were able to select four different type-regions located on the equatorial belt of Ganymede. The choice is based on the high density and homogeneous spatial distribution of the grooves located on those regions, which is necessary for the following analysis. The four datasets are in selected regions located in Uruk Sulcus, Babylon Sulci, Phrygia Sulcus and Mysia Sulci, respectively. We investigate the main characteristics of Ganymede’s grooves populations on the four different areas analyzing i) the grooves length distribution to describe the propagation and growing evolution of the faults underlying grooves systems. and ii) the grooves self-similar clustering to infer their vertical penetration inside Ganymede icy shell. Results and Discussion From the length distribution analysis, we found the presence of both an exponential and power-law trends reflecting the possible coexistence of (i) distributed fault systems, with strain regularly partitioned along evenly spaced faults and confined within specific mechanical layers in the crust (exponential fitting curve/curves) and (ii) localized fault systems, with few large faults cutting across the whole crust (power-law fitting curve) [e.g., 2,4]. From the self-similar clustering analysis, we estimated the potential thickness of the icy crust ranging between 105 and 130 km for the datasets considered. This value agrees with independent estimates of the thickness of the icy shell (from 80 to 150 km, [12,13,14]). Hence, our results support the hypothesis of shorter structures vertically confined in different mechanical layers within the icy crust and few very long faults propagating down to the liquid ocean underneath. Acknowledgements The activity has been realized under the ASI-INAF contract 2018-25-HH.0. References [1] Benedicto, A et al. (2003), Geophysical Research Letters, 30, 20, 2076. [2] Soliva, R., and Schultz, R.A., (2008), Tectonics, 27, TC2003. [3] Gudmundsson, A., et al. (2010), Journal of Structural Geology, 32, 1643-1655. [4] Schultz, R.A., et al. (2010). In: Planetary Tectonics, Cambridge University Press, 457-510. [5] Gudmundsson, A., et al. (2013), Tectonophysics, 608, 1298-1309. [6] Mazzarini F., D’Orazio, M. (2003), Journal of Volcanology and Geothermal Research, v. 125, p. 291-305. [7] Mazzarini, F., (2004), Geophysical Research Letters, v. 31. [8] Mazzarini, F., Isola, I. (2010), Geosphere, v. 6, p. 567-582. [9] Lucchetti, A. et al.,. (2017), Icarus, 297, 252-264. [10]Rossi, C. et al., (2020) Journal of Maps. [11] Collins, G.C., et al., 2013. Global geologic map of Ganymede: U.S. Geological Survey Scientific Investigations Map 3237. [12] Schenk, P.M. (2002), Nature, 417-419, 21. [13] Kivelson, M.G. et al., 1996. Nature, 384, 537-541. [14] Saur, J. et al., 2015. JGR Space Physics, 120, 1715-1737.

The European Space Agency’s Rosetta mission was designed to orbit and land on the Jupiter-family comet 67P/Churyumov-Gerasimenko (hereafter 67P) for the first time. To investigate the nucleus, the Optical, Spectroscopic, and Infrared Remote Imaging System [1] was designed. The OSIRIS instrument consisted of two cameras operating from near ultraviolet to near infrared wavelengths. The Wide-Angle Camera (WAC) imaged the dust and the gas surrounding the nucleus with a spatial scale of 10.1 m/pixel at 100 km from the surface. The Narrow-Angle Camera (NAC) investigated the comet nucleus and its surface topography with a spatial scale of 1.86 m/pixel at the same distance. The surface of comet 67P immediately appeared geologically complex, with a large variety of terrains and geological features [2]. In addition, the OSIRIS observations revealed a dichotomy in appearance between the two hemispheres. In particular, the northern regions are almost fully covered by dust [2, 3]. On the contrary, in the equatorial regions, consolidated and coarse terrains seem to have replaced the dust on the surface [4]. This dichotomy is linked to the insolation and subsequent erosion of the surface [5]. The dust cover in the northern regions is the result of transport mechanisms of particles from the southern hemisphere during the southern summer [5, 6]. The strong insolation and the water ice content in the south could erode the surface up to 20 m [5] at the perihelion. Method and results By applying the method developed by Cambianica et al. (2020) [6], we monitored the erosion and accretion of dust deposits of the Imhotep, Hatmehit, and Ma’at regions (Fig. 1) with a vertical accuracy of 0.4 m. The tool is based on the measurement of the shadow length projected by a boulder on the surrounding pebbles deposit. In Fig. 2 an example of the height measurement is shown. After assuming that the position of the boulder did not change during the observational period [7], any height variations provide an indication of how the thickness of the surrounding dust layer is varying in time through erosion and accretion phenomena. We measured the height of three populations of boulders, and the analysis covers the period from August 2014, inbound the perihelion, to September 2016, outbound. Our results show that equatorial regions remain almost inactive before perihelion, contrarily to the Ma’at region which shows erosion during the inbound orbit, and a subsequent dust deposit during the perihelion cometary activity. These results are in line with those found for the Hapi region [6], for which an erosion of the dust deposit of about 1.7 m during the inbound orbit and a fallout of 96% during perihelion cometary activity were measured [6]. Comparing our results with those obtained for the Hapi region, we confirm that the amount of the erosion in the southern hemisphere may be linked with the transport mechanism of the eroded material, and then to its fallout on the nucleus, justifying the presence of coarse terrain only in the southern hemisphere. Fig. 1. OSIRIS NAC images showing the analyzed boulder populations located in the Imhotep (A), Hatmehit (B), and Ma’at (C) regions of 67P respectively. The first image of this set (A) was taken on 23 November 2014, at a distance of 30.1 km and a scale of 0.57 m/px. Image B was taken on 23 July 2016 at a distance of 10.22 km and has a scale of 0.19 m/px, while the last one (C) was taken on 13 September 2014 at a distance of 30.1 km and a scale of 0.56 m/px. White circles indicate the measured boulders. Fig. 2. (a) NAC view of the Ma’at region. This image was acquired in 2014. (b) Close-up of a boulder and of its shadow. The green line represents the projection of the Sun illumination direction. (c) Boulder section. The y-axis is oriented as the normal to the average plane around the peak of the shadow. The x-axis is obtained by projecting the green line in panel b on this average plane; the x-axis origin coincides with the peak of the shadow. Acknowledgements OSIRIS was built by a consortium of the Max-Planck-Institut für Sonnensystemforschung, in Göttingen, Germany, CISAS-University of Padova, Italy, the Laboratoire d’Astrophysique de Marseille, France, the Instituto de Astrofísica de Andalucia, CSIC, Granada, Spain, the Research and Scientific Support Department of the European Space Agency, Noordwijk, The Netherlands, the Instituto Nacional de Tecnica Aeroespacial, Madrid, Spain, the Universidad Politechnica de Madrid, Spain, the Department of Physics and Astronomy of Uppsala University, Sweden, and the Institut für Datentechnik und Kommunikationsnetze der Technischen Universität Braunschweig, Germany. The support of the national funding agencies of Germany (DLR), France (CNES), Italy (ASI), Spain (MEC), Sweden (SNSB), and the ESA Technical Directorate is gratefully acknowledged. We thank the ESA teams at ESAC, ESOC and ESTEC for their work in support of the Rosetta mission. References [1] Keller, H. U., Barbieri, et al. (2007). Osiris, the scientific camera system onboard Rosetta. Space Science Reviews, 128(1-4):433–506. [2] Thomas, N., Sierks, H., et al. (2015). The morphological diversity of comet 67P/Churyumov-Gerasimenko. Science, 347(6220):aaa0440 [3] El-Maarry, M. R., Thomas, et al. (2015). Regional surface morphology of comet 67P/Churyumov-Gerasimenko from Rosetta/Osiris images. Astronomy & Astrophysics, 583:A26. [4] Keller, H. U., Mottola, S., et al. (2017). Seasonal mass transfer on the nucleus of comet 67P/Chuyumov–Gerasimenko. Monthly Notices of the Royal Astronomical Society, 469(Suppl_2):S357–S371. [5] Keller, H. U., Mottola, et al. (2015). Insolation, erosion, and morphology of comet 67P/Churyumov-Gerasimenko. Astronomy & Astrophysics, 583:A34. [6] Cambianica, P., Fulle, M., Cremonese, et al., (2020). Time evolution of dust deposits in the Hapi region of comet 67P/Churyumov-Gerasimenko.\ Astronomy and Astrophysics 636, A91. [7] Cambianica, P., Naletto, G., Cremonese, G. et al. 2019. Quantitative analysis of isolated boulder fields on comet 67P/Churyumov-Gerasimenko.\ Astronomy and Astrophysics 630, A15.

Mercury geology reached a new era after the MESSENGER mission, which has allowed not only to acquire global information but also to study the geological history of the planet with multiple techniques. The orbital BepiColombo mission will be the next step to fix some of the Hermean paradigm because more techniques, coupled with the higher resolution of the instruments onboard Mio and Bepi.Integration of compositional data and morpho-stratigraphic maps generally produced from camera data, will be one of the main issue to improve the understanding of Mercury geological evolution. This goal is also correlated with the efforts of other projects such as PLANMAP European H2020 and GMAP Europlanet 20-24.Several morpho-stratigraphic maps of Mercury quadrangles have been produced, or are ongoing (e.g. Galluzzi et al. 2018), and a global map has been realized (e.g. Kinczyk et al. 2019). Discussion or integration at quadrangle level of Mercury is recently beginning (e.g. Bott et al. 2019; Zambon et al. 2019) and here we report activity done in the Kuiper H06.Kuiper (H06) is an equatorial quadrangle, and it encompasses the area between longitudes 72°W –0° and latitudes 22.5°N – 22.5°S. H06 morpho-stratigraphic mapping is still ongoing (Giacomini et al. 2018; 2019), it evidences a high variegation of units, from older intercrater plains to younger smooth plains, to craters. Several craters show pyroclastic deposits (e.g. Kerber et al. 2011; Pajola et al. 2020), in some cases with putative vents, and hollows. Some of the hollows look like very peculiar from spectral point of view, e.g. in Dominici Crater (Vilas et al. 2016; Lucchetti et al. 2018), showing possible indication of mineralogical phases. Whereas most smooth plains are limited in extension and confined on the floor of the largest craters, a wide smooth plain has been detected that surrounds Rudaki crater. Some of these plains show clearly color variegation (e.g. two color units within Renoir Basin, see Giacomini et al. 2018).Due to the low latitudes, the coverage from MDIS data with high spatial resolution is lower than the northern quadrangles (e.g. Bott et al. 2019; Zambon et al. 2019) and we approach the study in a multiple-stage passages. This has been done to investigate the region with the best detail from a spectral point of view. Following the mosaic product procedure used by Zambon et al. (2019), we generate a homogeneous 8 color global mosaic at 1600 m/px scale (average scale taking into account the average resolution) and at 665 m/px pushing the resolution. Moreover, we considered the partial quadrangle coverage mosaics at 385 m/px and 246 m/px to exploit the presence of higher resolution color images.We will show spectral variations considering specific indices and color combinations (example on Figure 1), discussing the possibility to define some spectral units which could be later integrated with the morpho-stratigraphic mapping. Furthermore, we will locally investigate the spectral variation of specific cases, e.g. fresh craters, hollows and pyroclastic material, to infer some indication on material composition, or within some blue dark regions to understand the possible darkening material.This activity could be also helpful in the definition of indicators improving the selection procedure for regions of interest (see also Giacomini et al. 2020) to be studied for covering the science goals of the BepiColombo mission (e.g. Rothery et al. 2020).Acknowledgements:We gratefully acknowledge funding from the Italian Space Agency (ASI) under ASI-INAF agreement 2017-47-H.0. MM, CC, FZ, FA were also supported by European Union’s Horizon 2020 research grant agreement No 776276- PLANMAP. MM, CC, FA were also supported by Europlanet 20-24 GMAP, EPN-RI-2024.References:Bott N., et al. 2019. Global Spectral Properties and Lithology of Mercury: The Example of the Shakespeare (H‐03) Quadrangle. JGR-Planets, 124, 2326-2346.Zambon F., et al. 2019. Spectral properties of the H05 Hokusai quadrangle on Mercury and relationship with the morpho-stratigraphic units. EGU 7796.Giacomini L., et al. 2018. Updates on geologic mapping of Kuiper (H06) quadrangle. EPSC 721-1.Giacomini L., et al. 2019. GEOLOGICAL MAPPING OF THE KUIPER (H06) QUADRANGLE OF MERCURY. XV Congresso delle Scienze Planetarie, pg. 71.Giacomini L., et al. 2020. Scientific sites of interest in Kuiper Quadrangle (H06). EPSC this meeting.Kerber L., et al. 2011. The global distribution of pyroclastic deposits on Mercury: The view from MESSENGER flybys 1–3. PSS, 59, 1895–1909.Kinczyk M.J., et al. 2019. The First Global Geological Map of Mercury. EPSC-DPS 1045-1.Lucchetti A., et al. 2018. Mercury Hollows as Remnants of Original Bedrock Materials and Devolatilization Processes: A Spectral Clustering and Geomorphological Analysis. JGR-Planets, 123, 2365-2379.Pajola M., et al. 2020. MULTIDISCIPLINARY ANALYSIS OF LERMONTOV CRATER ON MERCURY. 51 LPSC 1402.Rothery et al. 2020. Rationale for BepiColombo studies of Mercury’s surface and composition. Spa.Sci.Review. in press.Vilas F., et al. 2016. Mineralogical indicators of Mercury's hollows composition in MESSENGER color observations. JGR 43, 1450-1456.

South Polar Aitken (SPA) is the largest and deepest basin on the Moon [1, 2], and several regions within this widespread basin have been considered as possible landing sites for present and future missions. Some of these sites are also targets of the H2020 n° 776276- PLANMAP project [3]. In this work, we focus on specific areas within SPA, Apollo basin, Lebinitz and Von Karman craters regions (see fig. 1). For our analysis, we considered the M3/Chandrayaan-1 data [4], after the application of the last calibration, thermal removal and photometric correction [5, 6]. SPA is rich in high Ca-pyroxenes, except for some central crater peaks, where low Ca-pyroxenes dominate, and no extensive olivine-rich areas are observed [1, 7, 8]. Based on the spectral characteristics on the M3 spectra, we define specific spectral parameters, such as band centers, depths, spectral slopes, including selected RGB color composite combinations [5]. These indices are the starting point for retrieving the spectral units of the regions considered. The final aim of this work is to find a link between spectral, and morpho-stratigraphic units [9] to reach out highly informative geological maps of the Moon. This innovative approach holds the efforts of different research units and is one of the main goals of the PLANMAP project. References: [1] Ohtake, M. et al., 2014, GRL. [2] Moriarty, D.P. et al., 2018, JGR. [3] https://www.planmap.eu/, [4] Pieters et al., 2009, Current Science., [5] PLANMAP D4.3- Spectral Indices and RGB maps. [6] Besse, S. et al., 2012, Icarus. [7] Dhingra, D., 2018, Geosciences. [8] Melosh, H. J., et al., 2017, Geology. [9] Ivanov, M.A., 2018, JGR. Acknowledgments: This work is funded by the European Union’s Horizon 2020 research grant agreement No 776276- PLANMAP. Figure 1: Apollo basin (top-left) and Leibnitz and Von Karman craters (bottom-left) reflectance map at 540 nm. Apollo basin (top-right) and Leibnitz and Von Karman craters (bottom-right) Clementine-like mosaic derived by M3 data (bottom-right).

Virtual Reality (VR, with headsets) and Augmented Reality (AR, using a smartphone or tablet) coupled with 3D photogrammetric reconstructions are increasingly used for science, education and outreach applications. These techniques are not new [e. g. 1, 2], but they are becoming progressively more widespread thanks to the release in 2016 of technologically mature and cost-effective hardware solutions accessible to the general public. In the field of planetology, VR and AR theoretically allow the possibility to simulate field trips to remote places that are otherwise inaccessible to humans. Using high-resolution imaging, coupled with spectral or morphological data gathered by robotic explorers (orbiters, landers, rovers), we can create integrated virtual environments that accurately represent the surface of planetary bodies and allow the cross-comparison of different datasets. These virtual environments provide the possibility to navigate on a global scale using orbital data, and move down to the surface when in situ data are available to visualize and analyze local outcrops. This is particularly the case of the Moon and Mars, where both extensive remote and groundtruth data are available [3, 4, 5]. We are investigating how the information from various sources can be combined in a comprehensive way to display, manipulate, analyze and share both analytical data and results. We have for example integrated visible high-resolution imagery, digital elevation and outcrop models, geomorphological maps and compositional maps derived from spectroscopic measurements on several test sites such as the Copernicus crater and Apollo 17 landing site on the Moon, the Crommelin crater and Kimberley area (Gale crater) on Mars, and the Hokusai quadrangle area on Mercury. The VR and/or AR rendering of simple orbital and/or ground-based 3D models can be performed using a web-based solution such as Sketchfab (e.g. https://sketchfab.com/LPG-3D or https://sketchfab.com/planmap.eu), offering the possibility to visualize, interact, and share medium-resolution 3D versions of these multi-scale data (Fig. 1a and 1b). The use of a more powerful and versatile solution based on a game engine [6] allows the development of more complex solutions, for example dedicated measurement tools (Fig. 1c) or multi-layering capabilities (Fig. 1d). These approaches offer new possibilities in terms of data exploration, analysis, and applications for research and education during “virtual planetary field-trips”. Acknowledgments: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 776276 (PLANMAP). References : [1] McGreevy (1993), M.W. Virtual reality and planetary exploration. In Virtual Reality; Elsevier: Amsterdam, The Netherlands,; pp. 163–197, ISBN 0-12-745045-9. [2] Favalli, M. et al. (2012), Multiview 3D reconstruction in geosciences. Comput. Geosci. 2012, 44, 168–176. [3] Ostwald, A.; Hurtado, J. 3D models from structure-from-motion photogrammetry using MSL images: Methods and implications. In Proc. of the 48th LPSC, The Woodlands, TX, USA, 2017. LPI Contribution No. 1964, id.1787. [4] Caravaca, G. et al. (2020) Planet Space Sci, 182, 104808, DOI: 10.1016/j.pss.2019.104808 [5] Le Mouélic, S. et al. (2020) Remote Sensing, 12 (11), DOI: 10.3390/rs12111900 [6] Nesbit, P.R et al. (2020), GSA Today, vol. 30, 4–10. DOI: 10.1130/GSATG425A.1

Chaotic terrains are broad regions on Mars characterized by the occurrence of angular-polygonal blocks separated by deep fractures and grabens, associated with collapse chains and with the overall mineralogy consisting mainly in basalts (Luzzi et al., submitted, 2020). Several mechanisms of formation for Chaotic terrains were proposed in the literature. While it is a shared opinion that the peculiar structures delineating the polygonal blocks of the Chaotic terrains are due to a collapse, the actual process at the origin of such collapse is still debated. Collapses due to the overpressure within a confined aquifer were proposed (Rodriguez et al., 2005; Andrews-Hanna & Phillips, 2007) as well as related to magma-ice/water interactions (Chapman & Tanaka, 2002; Leask et al., 2006; Meresse et al., 2008), or melting of a buried frozen lake (Zegers et al., 2010). We propose a new formation scenario for Chaotic Terrains: a Chaotic (or Piecemeal) Caldera collapse. In such a Caldera collapse the fragmentation of the floor is irregular and characterized by polygonal blocks. We reproduced this process in a series of analogue experiments similar to those performed by Troll et al. (2002): a rubber membrane was used to simulate the magma chamber with multiple cycles of inflation and deflation that generate the characteristic fractures in an overlying K-feldspar sand layer. We performed the experiments in different settings (different geometry of the magma chamber and different depth) and we found that the geometry of the basin is influenced mainly by the shape of the magma chamber. Moreover, after the second cycle of inflation and deflation, the deformation tends to be moderate, consisting only in the formation of minor fractures and not in deep structures, responsible for the polygonal blocks fragmentation, which are instead formed during the first cycles. From a morphological point of view, the reproduced geometry is strikingly similar to that of Chaotic terrains on Mars. Further quantitative analyses on the DEMs are ongoing in order to assess the role played by each variable and refine a plausible collapse history for the specific case of study of Arsinoes Chaos.REFERENCESAndrews-Hanna, J. C., & Phillips, R. J. (2007). JGR: Planets, 112(E8).Chapman, M. G., & Tanaka, K. L. (2002). Icarus, 155(2), 324–339.Leask, H. J. et al. (2006). JGR: Planets, 111(E8).Luzzi et al. (2020). EarthArXiv, DOI: 10.31223/osf.io/td297Meresse, S. et al. (2008). Icarus, 194(2), 487–500.Rodriguez, J. A. P. et al. (2005). Icarus, 175(1), 36–57.Troll, V. R. et al. (2002). Geology, 30(2), 135–138.Zegers, T. E. et al. (2010). Earth and Planetary Science Letters, 297(3–4), 496–504.

Rift-related faults often display non-rectilinear geometries, which have been interpreted as (i) the result of linkage between different fault segments -developed during a single or more tectonic phases-, (ii) as curvilinear faults due to gravitational collapse, (iii) as inherited basement trends. Disentangling these processes is generally difficult, with multi-phase rifting and reactivation of pre-existing structures being the most intuitive and commonly adopted explanations.Here, we use 3D seismic data to reconstruct the evolution of a couple of intersecting, curvilinear faults in the Horda Platform (Northern North Sea), which is characterised by a complex history of reactivation and multi-phase extension during the Jurassic-Cretaceous rifting. By reconstructing the three-dimensional geometry of the fault planes, we highlight that one fault follows the trend of the Permian-Triassic rift along its entire length, whereas the other, strongly curvilinear, fault appears to be partially deflected from it. By using time-thickness maps and kinematic analyses, we show that the partially deflected fault initiated in the Late Jurassic, soon after the other one (which activated in the Middle Jurassic). Notably, the younger fault flexes from the inherited Permian-Triassic trend as it approaches the other, more mature, fault, getting perpendicular to -and finally crosscutting- it. Hence, the curvilinear geometry developed during the upward propagation of the fault plane during the Jurassic-Cretaceous rifting, suggesting that such change of strike was driven by the influence of the more mature fault and is not due to structural inheritance. Similar deflections can be observed also in other areas of the dataset, with incipient faults flexing towards more mature structures.More generally, newer faults have been shown to deflect perpendicularly to pre-existing faults both in analogue and numerical models, suggesting we are facing a general process. These strike deflections suggest a stress re-orientation in the vicinity of well-developed structures, and not just simply a stress-drop as widely indicated by fault spacing and throw distribution of parallel faults. This is consistent with observations on deflected normal faults developing in correspondence to oblique basement fabrics as well as with the numerical model of the stress field by Homberg et al. (1997). Hence, our three-dimensional analysis of fault geometries suggests that the well-established concept of “fault-related stress-drop” should be broadened into the concept of “fault-related stress-reorientation”. ReferencesHomberg, C., Hu, J.C., Angelier, J., Bergerat, F., Lacombe, O., 1997. Characterization of stress perturbations near major fault zones: insights from 2-D distinct-element numerical modelling and field studies (Jura mountains). Journal of Structural Geology 19, 703–718. https://doi.org/10.1016/S0191-8141(96)00104-6

Tsiolkovskiy is a 180 km diameter late Imbrian crater located at 20.4° S, 129.1° E on the far side of the Moon [Whitford-Stark & Hawke, 1982].Compared to the extensive mare deposits present of the lunar side facing the Earth, Tsiolkovskiy crater represents one of the few basaltic exposures on the far side [Pieters & Tompkins, 1999]. Along with its particularly dark and smooth crater floor, the impact crater is also characterized by a morphologically well-shaped central peak on which has been detected both olivine [Corley et al., 2018] and PAN [Ohtake et al., 2009; Lemelin et al., 2015].The area represents thus a potential scientific site of interest for a safe landing. The production of geological maps aiming at characterize Tsiolkovskiy crater will allow the definition of interesting locations for rover exploration.A geomorphological mapping of the crater has been performed using the ~100m/pixel LRO-WAC [Robinson et al., 2010] global mosaic along with the ~59m/pixel LRO-LOLA and Kaguya TC DEM merge which has a vertical resolution of 3-4m [Barker et al., 2016]. The mapping defined six units corresponding to the well-recognizable central peak and the texturally different smooth and hummocky materials constituting the crater floor units, and by scarps with slopes >40°, isolated ponds of smooth material discernible from the rough material constituting the crater rim and constituting the crater walls units.The geomorphological mapping has then been coupled with a spectral characterization of Tsiolkovskiy crater performed on the basis of the ~200m/pixel Clementine UVVIS false color composite (Red 750/415nm; Green 750/1000nm; Blue 415/740nm) [Lucey et al., 2000]. The spectral mapping allowed to discriminate different units characterized by different origin and composition. In particular, the morphologically smooth crater floor unit is composed by fresher basalts and basaltic soils, the steep scarps and the central peak units are mostly composed by norites, troctolites and anorthosites, while the remaining smooth ponds, crater rim and the hummocky crater floor units are generally composed by mature highland soils.In order to define landing ellipses and broad traverses for a rover exploration of the site, the geological mapping is also been supported by an ongoing high-resolution mapping of a quarter of Tsiolkovskiy crater by means of a mosaic of ~0.5m/pixel LRO-NAC [Robinson et al., 2010] images here scaled to 3m/pixel.Finally, a radar investigation for the presence of deep structures will be performed to possibly detect lava pile emplacements and voids in the crater subsoil.AcknowledgmentsThis research was supported by the European Union’s Horizon 2020 under grant agreement No 776276-PLANMAP.ReferencesWhitford-Stark, J.L. & Hawke, B.R., XXXIII LPSC, pp. 861-862, 1982Barker, M.K. et al., Icarus, Vol. 273, pp. 346-355, 2016Pieters, C.M. & Tompkins, S., JGR, Vol. 104, pp. 21935-21949, 1999Corley, L.M. et al., Icarus, Vol. 300, pp. 287-304, 2018Ohtake, M. et al., Nature, Vol. 461, pp. 236-241, 2009Lemelin, M. et al., JGR: Planets, Vol. 120, pp. 869-8878, 2015Robinson, M.S. et al., Space Sci. Rev., Vol. 150, pp. 81–124, 2010Barker, M.K., et al., Icarus, Vol. 273, pp. 346-355, 2016Lucey, P.G. et al., JGR, Vol. 105, pp. 20377-20386, 2000

The numerous past and present space missions dedicated to the Solar System planetary bodies exploration, provided a huge amount of data so far. In particular, data acquired by cameras and spectrometers allowed for producing morpho-stratigraphic and mineralogical maps for many planets, satellites and minor bodies. Despite the considerable progresses, the integration of these products is still poorly addressed. To date, no geological maps of planetary bodies other than the Earth, containing both the information, are available yet. In this context, one of the main goals the “European Union's Horizon 2020 - PLANetary MAPping (PLANMAP)” project [1] is to provide, for the first time, highly informative geological maps of specific regions of interest on the Moon, Mercury and Mars, taking into account datasets publicly available in the Planetary Data System (PDS) database [2].Here, we show the results achieved during the first two years of the project by the PLANMAP “Compositional unit definition Work Package”. In particular, we focused on specific areas, such as Hokusai quadrangle (22°-60° N, 0°-90°W) and Beethoven (13.24°S- 28.39° S; 116.1°- 132.32°W, 630 km diameter) and Rembrandt (24.58°S- 41.19°S, 261.72°- 282.73°W, 716 km diameter) basins on Mercury, and the Apollo basin (10 ° –60 ° S, 125 ° –175 ° W, 492 km diameter) within the northeastern edge of the ~ 2500 km South Pole-Aitken (SPA) basin on the Moon [3]. For this work, we considered the multi-color images acquired by the Mercury Dual Imaging System - Wide Angle Camera (MDIS-WAC) [3] onboard the MESSENGER mission and hyperspectral data provided by the Moon Mineralogy Mapper (M3) [4] onboard the Chandrayaan-1 mission. After data calibration and the instrumental artifacts removal, we have photometrically corrected the data to derive multi- and hyper-spectral reflectance maps, afterwards we defined appropriate spectral indices to eventually obtain the spectral unit maps of these regions of interest. In next step, we will integrate the spectral unit maps obtained with the morpho-stratigraphic ones provided by other PLANMAP work packages [5, 6, 7] to merge the information and finally retrieve geological units. This work is funded by the European Union’s Horizon 2020 research grant agreement No 776276- PLANMAP and by the Italian Space Agency (ASI) within the SIMBIO-SYS project (ASI-INAF agreement 2017-47-H). References [1] https://planmap.eu/[2] https://pds.nasa.gov/[3] S. Edward Hawkins III et al., 2007, Space Science Reviews, 131, 247–338.[4] Pieters, C. E. et al., 2009, CURRENT SCIENCE, 96 (4).[5] Brandt, C. et al., 2020 EGU General Assembly 2020.[6] Ivanov, M.A., et al., 2018, Journal of Geophysical Research, 123 (10), 2585-2612.[7] Wright, J., et al., 2019, 50th Lunar and Planetary Science Conference.

Geologic mapping is a key element of planetary exploration for mission planning, orbital and rover reconnaissance, and target selection for in-situ analysis and sample return, as well as for understanding the formation and evolution of planetary surfaces. The PLANMAP project (http://www.planmap.eu) aims at produce high-level, standardized geological maps of the Moon, Mars, and Mercury (Massironi M. et al., 2018). The project is integrating different types of data as images, spectral-cubes, chemical data, Digital Terrain Models and three-dimensional geological models to produce geological maps suitable to planetary exploration at different levels. The process results in rich datasets composed by a variety of datatypes encapsulated in open standards and released to the community as freely accessible packages (https://maps.planmap.eu).To accomplish the complexity of deploying PLANMAP packages, considering reliability and automation as key components of a data release workflow, we arranged a data management framework respecting the FAIR (findable, accessible, interoperable, and reusable) guidelines. Geographic data are stored and served by a multi-layered Web-GIS allowing easy information discovery. Particular attention has been paid in designing the user interface and in the definition of the underlying data structure. Different data query services are also provided to properly address different user needs (Luzzi E. et al., 2020). PLANMAP’s datasets can be downloaded in the form of fully contained packages (https://data.planmap.eu) fulfilling a specifically designed standard. Once a data package is ready for publication, validation and summary information extraction take place and the results are published together within the packages.We will here present an overview of the PLANMAP’s deployed data system, and the technical solutions that were adopted with the final goal of improving the quality standards of planetary geological maps.References:- Luzzi E. et al., 2020, “Tectono-magmatic, Sedimentary and Hydrothermal History of Arsinoes and Pyrrhae Chaos, Mars.”, EarthArXiv, doi:10.31223/osf.io/td297- Massironi M. et al., 2018, “Towards integrated geological maps and 3D geo-models of planetary surfaces: the H2020 PLANetary MAPping project”, EGU General Assembly 2018

The research project ‘Moon Mapping’ has been established in 2014 between the Italian and Chinese Governments to promote cooperation and exchange between undergraduate students from both countries. The operational phase of the project started in early 2015, and will end in 2017, for a total length of three years. The main aim is to train new scholars to be able to work on different kinds of remotely-sensed data collected over the Moon surface by the Chinese space missions Chang’E-1/2. The project coordination has been assigned to the Italian Space Agency for the Italian side and to the Center of Space Exploration, China Ministry of Education, for the Chinese side. Several Chinese universities and Italian national research institutes and universities have been officially involved in this project. Six main research topics have been identified: (1) map of the solar wind ion; (2) geomorphological map of the Moon; (3) data preprocessing of Chang’E-1 mission; (4) map of element distribution; (5) establishment of 3D digital visualization system; and (6) compilation and publication of a tutorial on joint lunar mapping.