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Chaos terrains are geologically young and extensively disrupted surface features of Europa, thought to be an expression of the subsurface ocean interacting with the surface. The most prominent examples of this terrain on Europa are Conamara Chaos, and Thera and Thrace Maculae, all prime targets for the upcoming JUICE and Europa Clipper missions to assess the astrobiological potential of Europa. Of the three features, Thrace Macula is currently the least studied and understood. It intersects both Agenor Linea to the north and Libya Linea to the south, two important regional-scale bands whose interaction with Thrace is yet to be fully unraveled, especially in terms of their relative ages of emplacement and activity. Through detailed structural mapping using Galileo Solid State Imager data and terrain analysis on Digital Terrain Models, we here develop a novel hypothesis on the mechanisms that have been involved in the study area. We find that Thrace Macula is bordered along most sides by preexisting strike-slip faults that have constrained its emplacement and areal distribution. We determine a sequence of events in the area involving the formation of Agenor Linea, followed by that of Libya Linea first and Thrace Macula later, and ultimately by strike-slip tectonic activity driven by Libya Linea and displacing a portion of Thrace Macula. Therefore, Thrace’s subsurface material, uprising along faults postdating its formation, likely represents the freshest possible that could be sampled by future spacecraft in this region, a major consideration for the upcoming Europa Clipper mission.

International audience; INTRODUCTION: Organic compounds in asteroids and comets contain information about the early history of the Solar System. They could also have delivered organic material to early Earth. The Hayabusa2 spacecraft visited the carbonaceous asteroid Ryugu and collected samples of its surface materials, which were brought to Earth in December 2020. RATIONALE: We investigated the macromolecular organic matter in the Ryugu samples, measuring its elemental, isotopic, and functional group compositions along with its small-scale structures and morphologies. Analytical methods used included spectro-microscopies, electron microscopy, and isotopic microscopy. We examined intact Ryugu grains and insoluble carbonaceous residues isolated by acid treatment of the Ryugu samples. RESULTS: Organic matter is abundant in the Ryugu grains, distributed as submicrometersized organic grains and as organic matter dispersed in matrix. The Ryugu organic matter consists of aromatic carbons, aliphatic carbons, ketones, and carboxyls. The functional group

Faults and fractures may emplace fresh material onto Europa's surface, originating from shallow reservoirs within the ice shell or directly from the subsurface ocean. Ménec Fossae is a region of particular interest as it displays the interaction of several geological features, including bands, double ridges, chaotic terrains, and fossae, within a relatively small area. These features might affect the emplacement of buried material and subsequent exposure of fresh volatiles, prime targets for the upcoming JUICE and Europa Clipper missions in order to assess Europa's astrobiological potential. Previous studies have already revealed that a deep central trough is present at Ménec Fossae, flanked by several subparallel minor troughs and by a few asymmetrical scarps with lobate planforms. The presence of such features has motivated this study, given its potential to provide clear indications on the tectonic regime involved. Through detailed geomorphological-structural mapping using Galileo Solid State Imager data and terrain analysis on Digital Terrain Models, we could develop a novel hypothesis on the formation mechanisms that might have been involved in the study area. We propose that Ménec Fossae has been shaped by transtensional (strike-slip with an extensional component) tectonic activity, as indicated by the orientation and relationship of the tectonic features present. Likely, such transtensional tectonism occurred above or associated with shallow subsurface water, consistent with the overall morphology and topography of the study area and the presence of chaotic terrains and double ridges. These results strengthen the case for widely distributed shallow water reservoirs within Europa's ice shell.

Introduction While the single image coverage of the currently available Context Camera (CTX, [1]) images converges to the full coverage of the surface of Mars, the individual images show offsets of tens to hundreds of pixels from their real ground position. Current efforts for ortho-rectification and lateral control use the MOLA data as a source for global reference and geometric correction (e.g., [2]). Towards the equator this approach is unprecise due to the large discrepancy of the spatial resolutions of the two datasets (6 m/px vs.463 m/px). Automatic point matching of image pixels to DTM pixels are not reliable, therefore usually the CTX pixels are matched to imagery datasets which are themselves controlled to MOLA, such as the THEMS IR dataset [3]. This of course is sensitive to error propagation. The HRSC team expects to finalise the creation of global mosaics consisting of bundle-block-adjusted DTMs and their corresponding image mosaics [4] by the end of the year 2023. These DTMs provide an internal photogrammetric precision better than the 50 m used as the grid size. The deviations from the MOLA profile heights are also less than this single pixel resolution value [5]. Their corresponding image mosaics provide precise pixel-by-pixel alignment to the respective DTM in 12.5 m/px resolution [6]. Here we show a first approach using these HRSC products as the global reference dataset for Mars, by creating a CTX quadrangle mosaic with absolute geodetic control to HRSC (and therefore also to MOLA). Methods Generally, first the HRSC DTM is used for the ortho-rectification of the CTX images instead of MOLA. After this geometric correction, the image mosaic is used as a reference for automatic point matching and co-registration. We then apply the well-established brightness correction in a similar way we are using it for HRSC [6]. Ultimately, we combine the multitude of images from a whole quadrangle together to a seamless mosaic and export it as a single image file. The general workflow of our processing pipeline is shown in Fig. 1. Figure 1: Flow chart of the proposed CTX processing workflow from single images to a complete mosaic. Owed to the large amount of single CTX images per HRSC tile, we use a database management system (DBMS) for storage and retrieval of the CTX data catalog. In the spatially-enabled DBMS we perform geometric queries by intersection with the HMC30 boundary with the CTX footprints. The map-projection and co-registration of the data is slow - processing time can be significantly increased by high-performance computing (HPC). We define the main tasks as array jobs: The ISIS [7] processing pipeline performs image ortho-rectification using the HMC30 DTM. The resulting nominally ortho-rectified CTX images show a significant offset to HRSC based on inaccurate spacecraft attitude control (see Fig. 2 left). For correction, we introduce a subsequent co-registration based on a phase correlation approach [8]. The consecutive brightness correction uses the same HRSC image mosaic as a radiometric reference. A final step for seamline creation and image export is performed outside of the cluster using Desktop GIS software. Figure 2: Image offsets between CTX image D02_027799_1580 (6.25 m/px) and HRSC HMC30 20W (12.5 m/px); left: CTX with nominal pointing after ISIS standard processing, offsets in red; middle: CTX co-registered to HRSC by global x/y shift, offsets in blue; right: CTX co-registered by warping to dense network of tie points, no visible offsets. Results In a first qualitative assessment of dividual single CTX images, we examined the pixel offsets between the nominal images and their co-registered counterparts. First we tried to translate the images only in x/y direction as a block, but there were significant remaining offsets, increasing in the along-track direction of the spacecraft (see Fig. 2 middle). We achieved better results by transforming the CTX image to the HRSC reference image by the use of a dense network of tie points (see Fig. 2 right). In the example given in Figure 2, the offsets measure about 170 m which corresponds to 27 CTX pixels, 13 HRSC image pixels and 3 HRSC DTM pixels. Based on the processing pipeline described above, we created a complete CTX mosaic of the HMC-20W quadrangle, which will be available on our mapserver (https://maps.planet.fu-berlin.de). The ISIS processing steps were successfully applied to all of the 2062 images intersecting the DTM boundary, and 1692 of the images were successfully co-registered to the HMC30 image mosaic. The processing of the complete CTX dataset consisting of 2062 single images with a resolution of 6.25 m/px took around 3 days on the cluster, but this time is highly dependent on the cluster utilization. Discussion The results of the co-registration with a success rate of 82% are better than we initially expected. The remaining visible image gaps might be filled either by adapted parameters for co-registration or by the addition of manual tie-points. The initial offsets between the nominally-processed CTX images and the HRSC DTM (3 pixels in our example) might be large enough to expect impacting geometric artifacts during the orthorectification process, which will not be removed by the co-registration. Therefore it is planned to include an additional iterative processing step by feeding the tie-points acquired from the co-registration back into the ISIS pipeline and perform a bundle-adjustment between the CTX image and HRSC as ground and height reference. Acknowledgements This work is supported by the German Space Agency (DLR Bonn), grant 50OO2204, on behalf of the German Federal Ministry for Economic Affairs and Climate Action. We thank the HPC Service of FU for computing time [9]. References [1] M. C. Malin et al., JGR Planets (E5 2007). [2] J. L. Dickson et al., LPSC 49, #2480. [3] S. J. Robbins et al., LPSC 52, #2066. [4] K. Gwinner et al., EPSC/DPS 13, 2019, #2006. [5] K. Gwinner et al., PSS 126 (2016). [6] G. G. Michael et al., PSS 121 (2016). [7] T. Sucharski et al. (2020), DOI: 10.5281/zenodo.3962369. [8] Q. Chen et al., IEEE TPAMI 16 (1994), pp. 1156–116. [9] L. Bennett et al. (2020), DOI: 10.17169/refubium-26754.

Direct link to the interactive map: https://maps.planet.fu-berlin.de/jezero Introduction: We welcome you to explore the landing site of the Mars 2020 Perseverance rover in an interactive hiking map loaded with orbital imagery, terrain data and virtual 3D panoramic views of Jezero crater and its surrounding area! The map allows fast zooming and panning for the exploration of the available data in several magnitudes of scale levels from far away until centimeter detail. It also seamlessly integrates several waypoints with pre-rendered virtual 360° panoramas and several real panoramas each stitched together from a multitude of single images of the MastcamZ instrument. System Design: The general architecture follows the principles used for the HRSC Mapserver [1], see Figure 1. In contrast to the Mapserver’s intended use as a science-based data-portal and dissemination platform, the Jezero map was also planned as an public outreach application. But it serves as the first prototype of a next-generation infrastructure for disseminating upcoming data products from Freie Universität. Major parts of the existing set-up could be re-used but had to be updated. The layer menu had to be completely re-designed as it was implemented statically and hard-wired into the main code, which made it impossible to maintain and update its module dependencies. The most fundamental changes to the HRSC Mapserver are: Integrated A-Frame panoramic views, enabled switching between map views and 3D/VR/AR scenes Sidebar element for improved user experience on mobile devices and small screens, by Tobias Bieniek (https://github.com/Turbo87/sidebar-v2) LayerSwitcher element integrated into the sidebar, by Matt Walker (https://github.com/walkermatt/ol-layerswitcher) Transition from OpenLayers 3 to OpenLayers 5 involving a major migration from the underlying Google™ Closure compiler infrastructure to ES-based modules Usage of the Parcel packager to bundle the application for production IAU2015-based Mars spatial reference system as the base reference Figure 1: Flow chart of the web-GIS application’s general system design outlining front-end (client) and back-end (server) components. Data: The base layer of the customized map consists of a merged data-set from three different instruments. The Mars Express High-Resolution Stereo Camera (HRSC, [2]) Mars-Chart 30 data [3] are used as reference data-sets providing the geodetically controlled topography base and the seamless base imagery covering the complete landing site. 33 single images of the Mars Reconnaissance Orbiter (MRO) Context Camera (CTX, [4]), empirically corrected for their inherent ”smile” effect and bundle-adjusted with absolute geodetic control to the HMC-13E tile [5]. The single CTX images have then been radiometrically normalized using the HMC13 tile as brightness reference with the well-established methods from [6], re-implemented and adapted to CTX. To provide the orbital image data from the landing site in the highest available detail, we included image and topography data from the MRO High Resolution Imaging Science Experiment (HiRISE, [7]). We use the ortho-rectified image mosaic provided by the Terrain Relative Navigation (TRN) team of the JetPropulsion Laboratory (JPL) [8], which provided sufficient alignment to the underlying CTX and HRSC reference data. All three data-sets have been colourised by the HRSC color channels using pan-sharpening techniques and logarithmically stretched to Byte format. Outlook: The new web-GIS client presented here will also serve as the prototype for the re-design of the HRSC Mapserver for data dissemination and download. Its unique features for single image visualization and download will be re-implemented and integrated into the new design. It will serve more image data products for time-series analysis and vizualitation, mainly the complete co-registered set of CTX images. Figure 2: Jezero front-end showing the inflow-channel Neretva vallesJezero delta as a map frame. The droplet icons are clickable and switch the interface from the web-based view to the 3D-virtual panorama view as seen in Figure 3. Figure 3: Jezero front-end showing the 3D-virtual panorama view of the ”Pliva Vallis” outflow channel. The underlying A-Frame library allows 360 degree-orientation in 3D or VR. Acknowledgements: This work is supported by theGerman Space Agency (DLR Bonn), grant 50OO2204, on behalf of the German Federal Ministry for Economic Affairs and Climate Action. References: [1] S.H.G. Walter et al., ESS 7 (2018). [2] R. Jaumann et al., PSS 55 (2007). [3] K. Gwinner et al., PSS 126 (2016). [4] M. C. Malin et al., JGR Planets (2007). [5] A. Neesemann et al., LPSC 52, 2021, #2509. [6] G. Michael et al., PSS 121 (2016). [7] A. S. McEwen et al., JGR Planets (2007). [8] R. L. Fergason et al., LPSC 51, 2020, #2020.

After 18 years in orbit Mars Express remains one of ESA’s most scientifically productive Solar System missions, with a publication record now exceeding 1450 papers. Characterization of the surface geology on a local-to-regional scale by HRSC, OMEGA and partner experiments on NASA spacecraft has allowed constraining land-forming processes in space and time. Recent studies characterized the geology of Jezero crater in great detail and provided Digital Elevation Model (DEM) of several equatorial regions at 50 m/px resolution. New maps and catalogues of surface minerals with 200 m/px resolution were released. MARSIS radar published new observations and analysis of the multiple subglacial water bodies underneath the Southern polar cap. Modelling suggested that the “ponds” can be composed of hypersaline perchlorate brines.Spectrometers and imagers SPICAM, PFS, OMEGA, HRSC and VMC continue adding to the longest record of atmospheric parameters such as temperature, dust loading, water vapor and ozone abundance, water ice and CO2 clouds distribution and observing transient phenomena. More than 27,000 ozone profiles derived from SPICAM UV spectra obtained in MY#26 through MY#28 were assimilated in the OpenMARS database. A new PFS “scan” mode of the spacecraft was designed and implemented to investigate diurnal variations of the atmospheric parameters. Observations of Tharsis region and Hellas basin contribute to mesoscale meteorology.ASPERA measurements together with MAVEN “deep dip” data enabled assessment of the conditions that lead to the formation of the dayside ionopause in the regions with and without strong crustal magnetic fields suggesting that the ionopause occurs where the total ionospheric pressure (magnetic + thermal) equals the upstream solar wind dynamic pressure.In 2021 Mars Express successfully performed two types of novel observations. In egress-only radio-occultations a two-way radio link was locked at a tangent altitude of about 50 km. This is well below the ionospheric peak and would allow perfect sounding of the entire ionosphere thus doubling the number of ionospheric soundings. MEX and TGO performed several test UHF occultations. The dual-spacecraft radio-occultation technique would allow much broader spatial distribution of the missions’ radio occultation profiles. Mars Express is extended till the end of 2022. A science case for the mission extension till the end of 2025 will be developed and submitted in March 2022. The talk will give the Mars Express status, review the recent science highlights, and outline future plans including synergistic science with TGO and other missions.

Context. After landing on C-type asteroid Ryugu, MASCOT imaged brightly colored, submillimeter-sized inclusions in a small rock. Hayabusa2 successfully returned a sample of small particles from the surface of Ryugu, but none of these appear to harbor such inclusions. The samples are considered representative of Ryugu. Aims. To understand the apparent discrepancy between MASCOT observations and Ryugu samples, we assess whether the MASCOT landing site, and the rock by implication, is perhaps atypical for Ryugu. Methods. We analyzed observations of the MASCOT landing area acquired by three instruments on board Hayabusa2: a camera (ONC), a near-infrared spectrometer (NIRS3), and a thermal infrared imager. We compared the landing area properties thus retrieved with those of the average Ryugu surface. Results. We selected several areas and landforms in the landing area for analysis: a small crater, a collection of smooth rocks, and the landing site itself. The crater is relatively blue and the rocks are relatively red. The spectral and thermophysical properties of the landing site are very close to those of the average Ryugu surface. The spectral properties of the MASCOT rock are probably close to average, but its thermal inertia may be somewhat higher. Conclusions. The MASCOT rock can also be considered representative of Ryugu. Some of the submillimeter-sized particles in the returned samples stand out because of their atypical spectral properties. Such particles may be present as inclusions in the MASCOT rock.

Introduction The formation of Ganymede’s light terrain and its possible interaction with a subsurface ocean, have made its investigation one of the top goals of the upcoming JUICE mission [1, 2]. In this study we present a detailed stratigraphic analysis of areas that were observed by the Galileo SSI camera at highest possible spatial resolution (scales of ~11 m/pxl) in order to see what information of the light terrain’s stratigraphic position in Ganymede’s surface evolution can be gained from mapping and crater counting results and to identify what still has to be done in order to prepare for the upcoming JUICE mission. Study areas Based on the available data set, we selected four major regions (Region A, B, C and D) that are covered by more than one high-resolution SSI image for our study (Fig. 1): Region A and D from the anti-Jovian hemisphere and Region B and C from sub-Jovian hemisphere. Region A comprises of Byblus Sulcus (G2GSGRVLNS01), Nippur and Philus Sulcus (G2GSNIPPUR01) and the Transitional region (G2GSTRANST01) with the context info provided by the SSI observation G8GSREGCON01. Region B is dominated by Arbela Sulcus (28GSARBELA01+02/ G7GSNICHOL01), Region C is the Harpagia Sulcus region (28GSBRTDRK02, 28GSCALDRA02 and 28GSSMOOTH02) and Region D comprises Erech Sulcus (G8GSERECH01), Mummu and Sippar Sulci (G8GSCALDRA01). Mapping results Geologic maps are prepared for the four regions using ArcGIS. The naming/categorization of geological units follows from [4, 5] but are refined and modified wherever necessary (Fig. 2). Among the light terrain units, ls and lg are the most commonly occurring than li. Stratigraphic correlation: On the whole, the relative ages from crater density measurements (Fig. 5) follow the mapping results. In brief, in Byblus Sulcus the two light terrain units are of similar age from crater counts while lg3 is younger than lg2 from crosscutting relationships. (Fig. 2). In case of Region B (Arbela Sulcus), we could find that the age relationship of the two light terrain units and two dark terrain units agree with the relative age inferred from crosscutting relationship (Fig. 3a) In more extensively resurfaced areas of the light terrain the situation appears to be more complex. In Region C, the terrain units ls also have comparatively higher age than lg terrain units (Fig. 3b-3d). In Region D the terrain units (Fig. 4) are highly interrupted by the secondary craters formed during the Osiris and Melkart impact events [6]. Discussion We used two most favored chronology models LDM (Lunar Derived Model by [7]) and JCM (Jupiter Comets Model by [8]) (Fig.6). In general, based on the LDM ages the crater densities point to a relatively high age of the light terrain units not much younger that the ancient dark terrain and could imply a relatively short time period of formation for most of our mapped light terrain units. This relatively high age fits into the theory that the light terrain could have formed as a direct result of internal differentiation followed by a global expansion [9]. On the contrary, the JCM derived ages point to a longer formation period of light terrain units around 2 Ga [9]. While the impact chronology in the Jovian system and of its satellites is still not fully solved, newest results infer that the craters on these bodies were created from members of a collisionally evolved impactor family, similar to those in the inner solar system [10]. This does not straightforwardly support the lunar-derived chronology model (LDM) by [7] but allows to derive a Ganymede-specific crater production function empirically from the lunar one. We used this production function to fit our crater distributions and to derive absolute model ages for both model chronologies [7][8]. Figure 1: Regions of Interest in this study with the available Galileo SSI coverage indicated. Figure 2: Geologic mapping results for Region A: a) Byblus Sulcus (G2GSGRVLNS01), b) Nippur and Philus Sulcus (G2GSNIPPUR01) and c) the Transitional region (G2TRANST01). The legend applies also to Figures 3 and 4. Figure 3: Geologic mapping results for Region B dominated by Arbela Sulcus (28GSARBELA01+02/ G7GSNICHOL01) and Region C by Harpagia Sulcus (b) 28GSBRTDRK02, c) 28GSCALDRA02 and d) 28GSSMOOTH02). Figure 4: Geologic mapping results for Region D comprises of a) Erech (G8GSERECH01) and b) Mummu and Sippar Sulci (G8GSCALDRA01). Figure 5: Comparison of relative ages of different terrain units from a) Region A (Byblus Sulcus), b) Region B (Arbela Sulcus), c) Region C (Harpagia Sulcus - 28GSBRTDRK02) and d) Region D (Erech Sulcus) based on crater size frequency distributions. Figure 6: Stratigraphic correlation of Region a) A, b) B, c) C and d) D in which relative ages are determined by plotting the N(10) values with respect to each terrain units and corresponding ages based on LDM [7] and JCM [8]models. Please note that ages of fresh impact craters such as Nergal (N), Kittu (K), Enkidu (E), Melkart (M) and Osiris (O) have been added as additional stratigraphic markers. Since terrain types often appear more than one time in a geologic map the different facies are indicated by different colors. References: [1] Grasset, O., et al.: Planetary and Space Science, 78, 1-21, 2013. [2] Stephan, K., et al.: Planetary and space science, 208, 105324, 2021. [3] Pappalardo, R. T., et al.: Jupiter: The Planet, Satellites and Magnetosphere, 363-396, 2004. [4] Collins, G.C., et al.: Global geologic map of Ganymede (p. 3237), US Geological Survey, 2013. [5] Patterson, G. W. et al.: Icarus, 207, 845-867, 2010. [6] Baby, N. R., et al.: LPI Contributions, 2678, abstr. #1350, 2022. [7] Neukum, G., et al.: LPSC XXIX, abstr. #1742, 1998. [8] Zahnle, K., et al.: Icarus 163, 263-289, 2003. [9] Bland, M. T. et al. : Icarus 200, 207- 221, 2009. [10] Bottke et al.: LPSC, #2638, 2022.

Perseverance’s Mastcam-Z instrument provides high-resolution stereo and multispectral images with a unique combination of spatial resolution, spatial coverage, and wavelength coverage along the rover’s traverse in Jezero crater, Mars. Images reveal rocks consistent with an igneous (including volcanic and/or volcaniclastic) and/or impactite origin and limited aqueous alteration, including polygonally fractured rocks with weathered coatings; massive boulder-forming bedrock consisting of mafic silicates, ferric oxides, and/or iron-bearing alteration minerals; and coarsely layered outcrops dominated by olivine. Pyroxene dominates the iron-bearing mineralogy in the fine-grained regolith, while olivine dominates the coarse-grained regolith. Solar and atmospheric imaging observations show significant intra- and intersol variations in dust optical depth and water ice clouds, as well as unique examples of boundary layer vortex action from both natural (dust devil) and Ingenuity helicopter–induced dust lifting. High-resolution stereo imaging also provides geologic context for rover operations, other instrument observations, and sample selection, characterization, and confirmation.

Dust and melt ponds have been studied on planetary bodies including Eros, Itokawa, and the Moon. However, depending on the nature of the regolith material properties and the location of the planetary body, the formation mechanism of the ponded features varies. On Eros and Itokawa, ponded features are formed from dry regolith materials whereas on the Moon similar features are thought to be produced by ejecta melt. On the surface of Vesta, we have identified type 1, ejecta ponds, and type 2, dust ponds. On Vesta type 1 pond are located in the vicinity of ejecta melt of large impact craters. The material is uniformly distributed across the crater floor producing smooth pond surfaces which have a constant slope and shallow depth. The hosting crater of melt-like ponds has a low raised rim and is located on relatively low elevated regions. Whereas, the type 2 ponds on Vesta reveal an undulating surface that is frequently displaced from the crater center or extends toward the crater wall with an abruptly changing slope. We suggested that for the production of the type 2 ponds, localized seismic diffusion and volatile-induced fluidization may be responsible for Vesta. Due to Vesta's large size (in comparison to Eros and Itokawa), the surface may have experienced local-scale rare high-amplitude seismic diffusion which was sufficient to drift fine material. Similarly, short-lived volatile activities were capable to transfer dusty material on to the surface. Segregation and smoothing of transferred material lack further surface activities, hindering the formation of smooth morphology.