The ongoing exploration of planets such as Mars is producing a wealth of data to define habitable environments beyond the Earth. The inferred presence of neutral to alkaline aqueous fluids on Mars in its early history suggests that many potentially habitable environments existed on the planet. Terrestrial analogues with similar chemical and physical properties are being explored and characterized in order to assess their suitability for triggering the Origin of Life on Mars. Recently, a novel Mars analogue site has been identified in the Bagno dell’Acqua Lake, which is located in the island of Pantelleria in Sicily (Italy). We report here that microbialite from the Bagno dell’Acqua Lake acts as an efficient catalyst for prebiotic processes, starting from a ternary mixture of well-recognized chemical precursors, including ammonium formate, diaminomalonitrile, and alpha-amino acids. Under thermal conditions, significant amounts of building blocks of both RNA and PNA were obtained. Furthermore, samples of the water from the Bagno dell’Acqua Lake have been found to promote the polymerization of the H-form of 3′,5′-cyclic GMP, resulting in the generation of RNA oligomers of up to 15 units in length.

We produced several mineral mixtures and measured their reflectance in the VNIR range (350–2,500 nm) with the aim of reproducing the spectral features observed by the rovers Perseverance and Curiosity in the Jezero and Gale Crater respectively. We chose two specific case‐study spectra of the rovers namely the Bellegarde #5 abrasion patch in Jezero and the Voyageurs target drill in Gale. After selecting a number of mineral components representative of the two sites we first produced several binary (two components) mixtures and measured their reflectance. The binary mixtures are characterized by systematic variations of mineral proportions and were used to assess specific aspects of the relationships between spectral properties and mineralogical composition of mineral mixtures. Based on the results from the binary mixtures we then produced multicomponent (4, 5 or 6 components) mixtures through an iterative approach in which the spectrum of each produced mixture is compared with a target spectrum and its mineralogical composition is adjusted to match the target spectrum as closely as possible. The retrieved mineral composition of the final mixtures was eventually used to infer the conditions of formation of the investigated target emphasizing how the mineralogical composition of a laboratory mixture can give insights into the environmental conditions experienced by the target rock.

We provide the first visible near-infrared (VNIR) reflectance spectroscopy characterization of a sample from the lunar feldspathic breccia NWA 13859. The sample is a 2 mm thick slab with an approximate area of 35 ± 2 cm². We characterized the spectroscopic variability by choosing and analyzing representative spots throughout the sample. Our results show a distinct spectral contribution from orthopyroxene, which, according to a preliminary mineralogical characterization, should be a minor phase in the sample. In a second step, we measured several spectra along a transect between a clast and the matrix. In order to oversample the signal, the points analyzed along the sample were partly superimposed to each other (80% areal superposition). The same approach was extended to a grid of points covering an area of about 8.6 cm², with the goal of obtaining a spatial resolution of the spectral parameters higher than the instrument’s spot size. Using this strategy, we obtained 2D maps of spectral parameters, which allowed us to infer the major mineralogical composition of the sample.

Reflectance spectroscopy remains the most important tool to remotely infer mineralogical and chemical information of Earth and planetary surfaces (Bishop at al. 2019). Meteorites represent a sampling of planetary bodies with variable differentiation degree, mineralogy, and chemistry. For this reason, an accurate laboratory characterization of meteorites is of crucial importance for the correct understanding of spectral features of planetary bodies. This is especially true for the VNIR spectral range (~ 0.3-2.5 µm) where most of the spacecraft instruments operate and earth-based telescopes work. On the other hand, IR spectroscopy is of paramount importance to detect subtle chemical and mineralogical variations in minerals and rocks. Here we report a spectroscopic and mineralogical characterization of a suite of ungrouped achondrites which do not fit any classification scheme and their origin, in terms of planetary bodies, is either unknown or highly uncertain. We acquired reflectance spectra in both VNIR (0.35-2.5 µm and IR (~600 to ~7000 cm-1 or ~2 – ~17 µm) spectral ranges. The spectroscopic characterization has been performed with a spatial resolution spanning two orders of magnitude (from ~ 5·10-5 to ~ 5·10-3 m) allowing us to relate the bulk spectroscopic response of the rocks with the spectroscopic features of their constituent minerals. Bidirectional reflectance (VNIR and bulk FTIR) measurements were performed at IAPS-INAF, µ-FTIR measurements were executed at DAFNE-Light synchrotron radiation facility at LNF – INFN, while EPMA and SEM analysis were performed at MEMA – Department of Earth Sciences of Florence. Our results show a wide chemical and mineralogical variation between the samples. The mineralogical and chemical variation is clearly reflected on spectroscopic features. In Fig 1 we report the MidIR reflectance spectra and SEM-EDS images for sample NWA 5400. Fig. 1a shows the bidirectional reflectance spectrum for the powders (spot size: 6 mm). Fig. 1b we report the SEM-EDS image of a small area of the sample with the detected phases indicated by different colors. In Fig. 1c we show the µ-FTIR results on the same area in (b). It is interesting to note how the µ-FTIR spectra of olivine are slightly different in term of band position and area likely indicating small chemical heterogeneities within the sample. Figure 1. FTIR/SEM-EDS results for sample NWA 5400. (a) Bidirectional FTIR reflectance spectrum on powdered sample [spot size:  6 mm]. (b) SEM-EDS (false colors) of a small area (1 x 0.6 mm) of the sample. The different colors correspond to the detected mineral phases. (c) µ-FTIR spectra collected in the same area showed in (b). Location of the spot analysis is marked by colored dots. Yellow area corresponds to the spatial resolution of the µ-FTIR analysis (150 x 150 µm) in this sample. Fig. 2(a) shows representative VNIR spectrum for high-pyroxene content meteorites like NWA 6704. Figure 2(b) shows a representative VNIR spectrum for medium-high content olivine samples like NWA 10503. The spectral features are highly dependent from modal abundances of mafic minerals (mainly olivine and pyroxene) so that it is possible to identify two main groups: olivine-dominant achondrites and pyroxene-dominant achondrites. Cloutis et al. (1986) proposed a plot to show the relationship between spectral features and olivine/pyroxenes content. The same plot was later considered by Gaffey et al. (1993) to discriminate the S-type asteroids on the basis of the band I center and the ratio between the area of band I and band II (BAR). Recently this relationship has been also used to relate spectral variation of achondrites and possible parental bodies (e.g. Carli et al. 2018; Lucas et al 2019) and is reported in Fig 3 for our samples. Figure 2. Typical VNIR reflectance spectra for pyroxene-dominant achondrites (a) and olivine-dominant achondrites (b) Reflectance spectroscopy coupled with a thorough mineralogical and geochemical investigation of meteorites proved to be a powerful technique to infer quantitative conclusions about their origin, history and associate them with their provenance. Using the plot originally proposed by Gaffey et al. (1993) we clustered our samples in four distinct regions which likely correspond to potentially four different family of small objects. µ-FTIR was instead successfully applied to retrieve small-scale information including mapping the chemical and mineralogical heterogeneities. Acknowledgments:  This research was supported by ASI-INAF n.2018-16-HH.0 (Ol-BODIES project) Figure 3. B I center vs BAR (from Gaffey et al. 1993) plot for the investigated samples     REFERENCES Bishop, J. L., Bell III, J. F., Bell, J., & Moersch, J. E. (Eds.). (2019). Remote Compositional Analysis: Techniques for Understanding Spectroscopy, Mineralogy, and Geochemistry of Planetary Surfaces (Vol. 24). Cambridge University Press. Cloutis, E. A., Gaffey, M. J., Jackowski, T. L., & Reed, K. L. (1986). Calibrations of phase abundance, composition, and particle size distribution for olivine‐orthopyroxene mixtures from reflectance spectra. Journal of Geophysical Research: Solid Earth, 91(B11), 11641-11653. Gaffey, M. J., Bell, J. F., Brown, R. H., Burbine, T. H., Piatek, J. L., Reed, K. L., & Chaky, D. A. (1993). Mineralogical variations within the S-type asteroid class. Icarus, 106(2), 573-602. Lucas, M. P., Emery, J. P., Hiroi, T., & McSween, H. Y. (2019). Spectral properties and mineral compositions of acapulcoite–lodranite clan meteorites: Establishing S‐type asteroid–meteorite connections. Meteoritics & Planetary Science, 54(1), 157-180. Carli, C., Pratesi, G., Moggi‐Cecchi, V., Zambon, F., Capaccioni, F., & Santoro, S. (2018). Northwest Africa 6232: Visible–near infrared reflectance spectra variability of an olivine diogenite. Meteoritics &...