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Kuiper quadrangle (H06) is located at the equatorial zone of Mercury and encompasses the area between longitudes 288°E – 360°E and latitudes 22.5°N – 22.5°S. A detailed geological map (1:3M scale) of the Kuiper quadrangle based on the high resolution MESSENGER data, was performed (Giacomini et al., 2018) (Fig.1).The main basemap used for H06 mapping was the MDIS (Mercury Dual Imaging System) 166 m/pixel BDR (map-projected Basemap reduced Data Record) mosaic. Additional datasets were also taken into account, such as DLR stereo-DEM of the region (Preusker et al., 2017), mosaics with high-incidence illumination from the east and west, and MDIS global color mosaic (Denevi et al., 2018). The geological map showed that the quadrangle is characterized by a prevalence of crater materials which were distinguished into three classes based on their degradation degree (Galluzzi et al., 2016): from C1, consisting on the most degraded craters, to C3, including the freshest ones. Different plain units were also identified and classified on the basis of their density of craterisation: (i) intercrater plains, densely cratered, (ii) intermediate plains, moderately cratered and (iii) smooth plains, poorly cratered. Finally, several structures, mainly represented by thrusts, were mapped all over the quadrangle.The mapping of quadrangle allowed the identification of canditate targets for the BepiColombo mission to Mercury (Fig.1). Indeed, volcanic features, as hollows and pyroclastic deposits, are widespread in the quadrangle. Their high-resolution analysis could give new information regarding the volcanism history on the planet.Also several faulted craters have been detected. They represent important indicators to understand the kinematic of the structures transecting the craters (e.g. Galluzzi et al., 2015). Therefore, they will allow us to gain new clues on the tectonic history of the planet surface, with important implications for the knowledge of the thermophysical evolution of Mercury.Further intriguing features are craters showing smooth ejecta with sinuous edges and a fluidized morphology. They have been called ejecta flows and they are thought to represent dry granular flows, although the presence of volatiles involved in the fluidization process can not be excluded (Xiao, 2013). Hence, high resolution data could give new inputs for the knowledge of the origin and evolution of these deposits.Where MDIS WAC images at high spatial resolution are available, a more detailed analysis of the spectral behaviour of the surfaces can be accomplished (Carli et al., 2020). This allowed us to integrate geomorphological and spectral characteristics for specific areas in order to obtain new information about the landforms’ origin. Such procedure was preliminary conducted on Renoir basin, where two smooth deposits, showing different spectral characteristics, have been detected in different areas of its floor. However, a higher spectral and spatial resolution are needed to better appreciate the differences on those deposits.In light of these evidences, it appears that the high resolution of the instruments of BepiColombo mission, like STC and HRIC cameras and VIHI spectrometer of SIMBIO-SYS, can significantly contribute to answer several questions raised during the geological mapping and analysis of the Kuiper quadrangle.AcknowledgementsWe gratefully acknowledge funding from the Italian Space Agency (ASI) under ASI-INAF agreement 2017-47-H.0. MM, CC, FZ were also supported by European Union’s Horizon 2020 research grant agreement No 776276- PLANMAP. References Carli et al., 2020. Kuiper Quadrangle spectral analysis: looking forward to integrated geological map. EPSC, this conference.Denevi et al., 2018. Calibration, Projection, and Final Image Products of MESSENGER’s Mercury Dual Imaging System. Space. Sci. Rev., 214: 2. https://doi.org/10.1007/s11214-017-0440-yGalluzzi et al., 2015. Faulted craters as kinematic indicators in planetary tectonics: application to Mercury. In: Volcanism and Tectonism across the Inner Solar System, vol 401. Geol.Soc. London Spec. Pub, pp. 313–325.Galluzzi et al., 2016. Geology of the Victoria quadrangle (H02), Mercury. J. Maps, 12, 226–238.Galluzzi et al., 2018. The Making of the 1:3M Geological Map Series of Mercury: Status and Updates. Mercury: Current and Future Science of the Innermost Planet. Abstract#6075.Giacomini et al., 2018. Updates on geologic mapping of Kuiper (H06) quadrangle. EPSC abstracts, 12, EPSC2018-721-1.Preusker et al., 2017. Toward high-resolution global topography of Mercury from MESSENGER orbital stereo imaging: A prototype model for the H6 (Kuiper) quadrangle. Planetary and Space Sci., 142, 26-37.Xiao, 2013. Impact craters with ejecta flows and central pits on Mercury. Planetary and Space Science, 82, 62-78.

Geological maps have been historically a central part of the geological knowledge acquisition process: they are used to summarize all the relevant information of a site of interest and they provide the cornerstone for decision making, scientific discovery and three-dimensional geological modeling. Depending on the scope of the geological survey the cartography can depict different types of content: whether lithostratigrapy, chronostratigrapy, morphology, or other criteria are considered, the building blocks of a geological map is the geological unit, as the base element used to subdivide a region into geologically homogeneous patches of terrain. Digitized maps are normally represented within GIS software as polygonal layers. A common approach for mapping has been to directly draw polygons representing the different units on the map: although this approach appears the simplest one, it poses several issues in terms of topological consistency of resulting maps, especially when it comes to updating existing cartography. Furthermore, from a purely information science standpoint this representation, although useful for visualization, is inherently redundant, defining the same boundary geometry two times for each polygonal couples in contact. Editing polygonal layers is inherently problematic because vertex and edge correspondence between polygons in contact must be enforced by the operator. Although most GIS software implements appropriate tools (for editing and for topology validation) which can help in achieving error-free polygonal layers, the burden of using them is left to the operator and it is not enforced by the data format itself. A better solution for generating topologically-consistent geological maps consists in tracing the contacts separating the units, and then transforming them into polygonal layers (by using what is often known as a “polygonize” operation) for map finalization (see Figure 1). Figure 1: Generation of a consistent polygonal layer by polygonize operation, this can be performed by any GIS and is suggested as a good practice in geological map generation. A line layer is used for tracing the contacts between the different units and a point layer is also needed to define attributes for the polygons. This approach is also more similar to the geological reasoning that is performed when mapping, especially when remotely -sensed imagery is used (as in planetary mapping): the operator tries to identify the boundaries between different terrains rather than directly defining the area covered by the units themselves. This strategy hasve the clear benefit of making editing the map easier but, even when employed by the operator, the original layers (contact lines and points) are rarely or never distributed to the public, making it impossible to apply this method when updating already existing maps. In order to solve this problem we implemented a python module and a QGIS plugin called Mappy which is mostly based on already-existent modules as numpy (Oliphant 2006), geopandas (Jordahl et al. 2019), and topojson (Bostock 2017). Mappy implements the backwards transformation of the polygonize operation decomposing a polygonal layer into boundary lines and a point layer that contains the attributes of the original polygonal layer (the forward transform is also implemented). The input polygonal layer is first transformed into a topology-aware representation via topojson: first the intersection points are detected and then the polygons boundaries are split at those points, creating a list of arcs: each representing an unique portion of a contact line (Figure 2). Topojson representation can also account for rounding errors in the nodes coordinates and makes it possible to also consistently apply line-simplification methods (e.g. to reduce the number of nodes) while maintaining the original topology. Figure 2: The inverse operation of a "polygonize" operation as performed by mappy. a) the input polygonal layers with attributes; b) the topojson representation as list of arcs (each polygon is then just a list of arcs in the right order); c) the arcs are aggregated to create a representation more suitable for geological editing; d) point are positioned in the visual center of each polygon and the attributes are then transferred. Although being topologically sound, the topojson format of a polygonal layer is not the best suited representation for editing geological maps: given each line is split at the intersection points (Figure 2b) a contact might be split in a number of segments (i.e. when a contact separates one unit from several others) making it more difficult to edit the contact of a specific unit. For this reason, Mappy further processes the lines to aggregate several continuous arcs into a single polylines (Figure 2c). For each polygon an indicator point is then automatically computed to be in its visual center and the original attributes of the polygons are transferred to it. The points are placed by using the “polylabel” method provided by shapely module (Gillies and others 2007). The described approach has been then implemented in a standalone module that is also accessible from a QGIS plugin enabling easy transformation of any existing map into a line and points representations and vice-versa, therefore simplifying the process of editing and topology checking of existent geological maps. Acknowledgments: This research was supported by European Union’s Horizon 2020 under grant agreement No 776276- PLANMAP. References: Bostock, Mike, 2017 TopoJSON. URL: https://github.com/topojson/topojson-specification. Gillies, Sean, and others, 2007 Shapely: Manipulation and Analysis of Geometric Objects. toblerity.org. https://github.com/Toblerity/Shapely. Jordahl, Kelsey, Joris Van Den Bossche, Jacob Wasserman, et al., 2019 Geopandas/Geopandas: V0.4.1. Zenodo. https://zenodo.org/record/2585849, accessed June 29, 2020. Oliphant, Travis, 2006 NumPy: A Guide to NumPy. https://www.numpy.org/.

Within the European Horizon-2020 project PlanMap - whose aim is to provide integrated cartography with spectral information, stratigraphy and 3D geologic models of the subsurface - several artists contributed in shaping the vision of geological exploration of planetary bodies of our Solar System for the wide public (https://planmap.eu/content/artists). We addressed a broad audience of kids, students and general public by means of dedicated artworks and the production of a project soundtrack. We realised the following initiatives: (a) The “Drawing for Kids” storyline tells the adventures of the project's mascot Geolyn who is portrayed in stand-alone contexts related to planetary geology and exploration. These paintings aim to present geological mapping to the young public depicting in a very friendly and simple way the mapping process; (b) The “Drawing the Future” illustrations aim to deliver the vision of a near future where the tools and the scientific products of Planmap become hands-on applications for the exploration of the Moon, Mars and Mercury. This storyline aims to engage secondary school students and the general public showing planetary landscapes explored through enhanced tools and augmented reality; (c) “Drawing the Comic” is an initiative that is regularly published in the PLaNCK! Magazine (www.planck- magazine.it) and narrates the adventures of Marie, Max, Planck and nanny Rose delivering accurate and correct scientific information using vocabulary and narrative strategy suitable for the target audience; (d) The Planmap soundtrack project led to the realization of a dedicated multi-instrument track within the ITH project which aims to explore the baffling emotions and feelings of dreams from the point of view of a blind child. ITH is a one man band project with exploration desire at its core and each song has references to space, stars and science. This initiative is supported by the European Union’s Horizon 2020 research and innovation program under grant agreement N°776276 (PLANMAP).

On the southern hemisphere of the lunar farside lies the interesting Tsiolkovskiy crater that presents on its floor one of the few exposures of mare volcanism on the far side and an unusually well-shaped central peak. Its morphology and the remotely-sensed detection of minerals such as olivine and Purest Anorthosite (PAN), make Tsiolkovskiy crater an area to be considered for a possible landing site for a rover-based exploration. With this objective we are carrying on a geological characterization of this crater. Introduction Tsiolkovskiy crater (20.4° S, 129.1° E) is a Late Imbrian impact crater with an elliptical shape and a minor axis diameter of about 180 km [1, 2]. Over the crater floor rises a ~3 km-high particularly bright and well-preserved central peak surrounded by an exclusively dark and smooth mare deposit formed by multiple eruptive events [2]. Moreover, on the central peak have been detected PAN [3, 4] and olivine [5]. The above-mentioned characteristics highlight the scientific interest represented by Tsiolkovskiy crater as a main driver to characterize its interior as landing site and evaluate the possibility to safely plan route traverses for rovers. Aiming to focus the strategy of exploration for a future lunar landing mission we are producing geological maps of the area in order to select locations of high interest and traverse paths for in-situ investigations and analysis in order to help unravel key scientific questions concerning the origin and evolution of the Moon, the structure and composition of the lunar crust and interior and the presence of volatiles and of minor and trace elements. Basemap datasets The geomorphological mapping of the impact crater has been carried out on the Lunar Reconnaissance Orbiter Wide Angle Camera [6] global mosaic with a resolution up to 100 m/pixel along with elevation data derived from the Lunar Orbiter Laser Altimeter and Kaguya Terrain Camera DEM merge [7] with an horizontal and vertical resolution respectively of about 59 m/pixel and 3-4 m. The surface morphology mapping has then been coupled with the spectral mapping performed on the ~200 m/pixel false color composite (Red 750/415 nm; Green 750/1000 nm; Blue 415/750 nm) generated using the Clementine UVVIS [8] reflectance image. Moreover, an high-resolution mapping is being produced on Lunar Reconnaissance Orbiter Narrow Angle Camera (NAC) [7] images along with NAC-derived DEMs both with a resolution of about 0.5 m/pixel. Results From the geomorphological mapping (Fig. 1) have been distinguished the following crater floor (CF) and crater walls (CW) units: ­ CF smooth material: very smooth and planar material with a sharp boundary with respect to adjacent materials, ­ CF hummocky material: rough material reworked during the impact and CW debris, ­ CF central peak: sharp and well-recognizable central peak morphology, ­ CW smooth ponds: smooth material areas texturally discording with respect to the surrounding areas, ­ CW steep scarps: exposed steep scarps with slopes >40°, ­ CW rim: terraces and scarps made up by collapsed material. The spectral mapping (Fig. 2), instead, has been performed on the basis of the different color of the units, associated to a different origin and composition of the materials. The mapping allowed the distinction of the following units: ­ Fresher basalts: predominant yellow color, corresponding to most of the CF smooth material, ­ Basaltic plain: predominant orange color, corresponding to the remaining CF smooth material unit, ­ Noritic-anorthosite/troctolite: light blue color, mostly correlated to the CF central peak and CW steep scarps units, ­ Anorthosite: blue color, mostly correlated to the CF central peak and CW steep scarps units, ­ Mature highland soil: red color, corresponding to the CW rim, CW smooth ponds and CF hummocky material units. Finally, in the area surrounding the central peak of Tsiolkovskiy crater is being produced an high-resolution geological mapping with the aim to better define the geological setting for a rover-based exploration. So far, the mapping allowed to highlight some interesting features such as mare rilles and wrinkle ridges in proximity to the peak. Fig. 1: Geomorphological mapping superposed on the hillshade generated from the Lunar Orbiter Laser Altimeter and Kaguya Terrain Camera DEM merge. Fig. 2: Spectral mapping superposed on the Clementine UVVIS Color Ratio. Conclusions and future work Here we presented the geomorphological and spectral mapping of Tsiolkovskiy crater performed so far. In the next future the high-resolution mapping will be completed and coupled with a spectral investigation by means of Chandrayaan-1’s Moon Mineralogy Mapper [9] data. Moreover, a radar investigation for the presence of deep structures, such as voids and lava pile emplacements, will be carried on by means of Kaguya Lunar Radar Sounder [10] data. To conclude, in order to perform a complete characterization of Tsiolkovskiy crater as a possible future landing site, we will perform a steepness and hazard analysis for the definition of the landing ellipses and route traverses for a rover exploration. Acknowledgements This research was supported by the European Union’s Horizon 2020 under grant agreement No 776276-PLANMAP. References [1] Whitford-Stark, J.L. & Hawke, B.R., XIII LPSC, pp. 861-862, 1982 [2] Pieters, C.M. & Tompkins, S., JGR, Vol. 104, pp. 21935-21949, 1999 [3] Ohtake, M. et al., Nature, Vol. 461, pp. 236-241, 2009 [4] Lemelin, M. et al., JGR: Planets, Vol. 120, pp. 869-8878, 2015 [5] Corley, L.M. et al., Icarus, Vol. 300, pp. 287-304, 2018 [6] Robinson, M.S. et al., Space Sci. Rev., Vol. 150, pp. 81–124, 2010 [7] Barker, M.K. et al., Icarus, Vol. 273, pp. 346-355, 2016 [8] Lucey, P.G. et al.,JGR, Vol. 105, pp. 20377-20386, 2000 [9] Pieters, C. M. et al., Current Science, Vol. 96, pp. 500-505, 2009 [10] Ono, T. et al., Space Sci. Rev., Vol. 154, pp. 145-192, 2010