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Phobos and Deimos, the two satellites of Mars, were largely studied in the past using ground-based telescope and spacecraft data, although most of the data were obtained by opportunity observations performed by Mars dedicated orbiters. Despite the data available so far, the main composition of the two moons is not yet fully understood. The possible presence of hydrated minerals along with mafic minerals olivine and pyroxene seems to be the most plausible interpretation, but more investigations are needed. MIRS spectrometer on-board the future JAXA MMX sample return mission will help to unveil the open question on the composition of Phobos and Deimos. In this work, we review past spectroscopic observations of the Martian moons, both from ground observatories and spacecraft data set, aiming at better understanding the constraints in interpreting the Mars satellites composition and at identifying the best spectroscopic analogues. We also present new laboratory measurements on mineral mixing and meteorites to match the satellites spectral behaviour. New measurements were acquired at INAF-Astrophysical Observatory of Arcetri and IPAG laboratories at room conditions exploring different geometries and the results obtained set new constraints for future laboratory measurements. Our preliminary results confirm that the surface of Phobos and Deimos can be associated with samples characterized by a higher presence of dark components (e.g. amorphous carbon) or minerals produced by space weathering (e.g. Fe0 and FeS-bearing materials). Presence of dark component could also be totally responsible for the reduced hydrated band observed on the moons without invoking dehydration or OH-implantation on anhydrous surface.

As soon as samples collected from Mars will be brought back to Earth, the samples will be placed inside a receiving facility to check for the presence of life. There is a large number of approaches that were proposed on the techniques to be used to investigate the presence of life and any biological risk in the returned samples. Another interesting approach was reported by Kminek in which suggestions were provided on how to organize the sample analysis sequence within the facility. Finally, another study suggested a long list of techniques capable of measuring biological signatures based on their general characteristics: global, morphological, mineralogical, organic, molecular and biochemical, isotopic analysis. Despite the effort of the cited studies, there is still the need of a critical approach to make an actual comparison between the techniques, with the aim to find a ranking. In this work, we focused on the construction of a correlation matrix with which to correlate biosignatures to analytical techniques. It is known that a number of techniques can detect biological signatures and, at the same time, each technique can be applied to multiple biological signatures. Using this method, it is possible to summarize all this information to be easily consulted, but also to define in a quantitative way how strong each correlation is.

The NASA Double Asteroid Redirection Test (DART) mission performed a kinetic impact on asteroid Dimorphos, the satellite of the binary asteroid (65803) Didymos, at 23:14 UTC on September 26, 2022 as a planetary defense test. DART was the first hypervelocity impact experiment on an asteroid at size and velocity scales relevant to planetary defense, intended to validate kinetic impact as a means of asteroid deflection. Here we report the first determination of the momentum transferred to an asteroid by kinetic impact. Based on the change in the binary orbit period, we find an instantaneous reduction in Dimorphos's along-track orbital velocity component of 2.70 +/- 0.10 mm/s, indicating enhanced momentum transfer due to recoil from ejecta streams produced by the impact. For a Dimorphos bulk density range of 1,500 to 3,300 kg/m$^3$, we find that the expected value of the momentum enhancement factor, $\beta$, ranges between 2.2 and 4.9, depending on the mass of Dimorphos. If Dimorphos and Didymos are assumed to have equal densities of 2,400 kg/m$^3$, $\beta$= 3.61 +0.19/-0.25 (1 $\sigma$). These $\beta$ values indicate that significantly more momentum was transferred to Dimorphos from the escaping impact ejecta than was incident with DART. Therefore, the DART kinetic impact was highly effective in deflecting the asteroid Dimorphos., Comment: accepted by Nature

Introduction: Ceres is the largest object of the Solar System main belt with a complex geological and chemical history, which experienced extensive water related processes and geochemical differentiation [1]. Ceres’ surface is characterized by dark materials, phyllosilicates, ammonium-bearing minerals, carbonates, water ice, and salts. In addition to a global presence of carbon-bearing chemistry, local concentration of aliphatic organics has been detected by Dawn mission [2]. The mission, thanks to the data collected by the Italian instrument VIR [3], showed clear evidence of a high amount of aliphatic organic material on the surface of Ceres [4, 5, 6]. This has raised new questions about the origin and preservation of this material, especially when considering its high estimated abundance (Fig 1). We started a series of laboratory studies on physicochemical evolution of organic material interacting with minerals thought to be present on Ceres. The goal is to understand the transformations induced on these samples by processing with ultraviolet radiation. Fig. 1 Ceres spectra of the organic-rich area in Ernutet crater (label “Organics”); of a background organic-poor area from a region southeast of Ernutet (label “Background”); and Occator bright material (label “Carbonate”) [4]. Results: In this study, we mixed organic material with a mixture of minerals considered a spectral analog of the Ceres surface. Specifically, we mixed undecanoic acid and solid material made of serpentine, magnetite, carbonate and ammonium bearing montmorillonite with a ratio of 1:80 (organic:mineral). Diffuse FTIR reflectance spectra were acquired in vacuum. Spectra of simulant are resembling the Ceres surface composition (Fig. 2) organic rich area, even if the proportions between the bands of clays, carbonates and organics are not the same as seen on Ceres. We irradiated the sample in the vacuum chamber at room temperature using an UV lamp to simulate the solar radiation. The photon flux was 2.75x1017 ph. cm-2s-1 in the 200-400 nm spectral range as measured through a single monochromator Spectro 320 spectrometer. The simulant was irradiated at increasing fluence up to irradiation time of about 7 hours and the degradation process was monitored in real time with FTIR spectroscopy by measuring the changes in the spectral features (band areas). In Fig. 4 the reflectance spectra of the simulant as prepared and after UV irradiation at 180, 2280, and 21180 s are showed. The bands area of NH3 at 3 μm and aliphatic CH2/CH3 at 3.4 μm are decreasing as the irradiation fluence increases with time. Fig. 2 Average spectrum of Ceres Ernutet organic-rich ares (black) compared to laboratory simulant (blue). Spectra are normalized at 2.6 μm. Each band area, which is proportional to the number of functional groups, was evaluated at different irradiation time and the degradation rate was obtained by fitting the band areas vs irradiation time using an exponential function. This method permits to determine the degradation cross section of each band, which is the probability that chemical bonds are broken by UV radiation. In particular, for the aliphatic band at 3.4 μm it was possible to obtain the degradation cross section of the whole band, 5.85x10-21 cm2. and of every single band component distinguishing between CH2 and CH3 bonds behavior under irradiation. In presence of mineral simulant, the degradation rate of aliphatic compounds extrapolated to the estimated UV flux at the surface of Ceres gives a half-lifetime of 215 days. This result coupled with resurfacing process time scale of million years could justify the absence of detectable organics on most of the Ceres’ surface. However, this result would not be able to explain the presence of organics in the organic-rich area in Ernutet crater. Furthermore, as can be seen from Fig. 3, UV radiation not only degrades the CH bonds but also affects the NH bonds present in the ammoniated silicates. In this latter case the degradation cross section for the whole band is 2.05x10-21 cm2 which is responsible of a less effective photodegradation process giving a degradation half-lifetime of about 613 days. This result also seems to be in contrast with the ubiquity of the presence of ammoniated silicates on Ceres. We have to recall that the experiments reported in this work have been done at room temperature. It is not excluded that photoprocessing at cryogenic temperature typical of Ceres surface can be less effective further reducing the degradation cross sections of CH and NH bonds. Discussion: As showed by VIR, the ammoniated band is ubiquitous on Ceres, which is in contrast with the fact that we expected the ammoniated band to be completely degraded. However, photodegradation acts on the first molecular layers of the surface exposed to the radiation. Furthermore, the visible and near infrared spectra detected by VIR are diffused by the first millimeters of the surface at a depth that cannot be affected by UV radiation. Therefore, the spectra are a combination of processed superficial material and underlying layers of the Ceres surface, which may retain the primitive characteristics of material rich in organic. However, it should be noted that in addition to UV, the surface is constantly bombarded by solar energetic particles (SEP) and galactic cosmic rays (GCR). This radiation also has the effect of breaking chemical bonds such as UV photons, but penetrating meters into the surface can alter deeper layers. These results suggest that there must be a resurfacing mechanism able to expose organic rich material that acts on a much shorter time scale than the geological one. Fig. 3 Diffuse reflectance spectra of the simulant as prepared (0 s) and after UV irradiation at 180, 2280, and 21180 s. Acknowledgements: This work is supported by INAF Main Stream program, grant “Evolution and alteration of organic material on Ceres”. References: [1] De Sanctis et al., 2016, Nature 536, 54–57 [2] Marchi et al., 2019, Nature Astr. 3, 140-145 [3] De Sanctis et al., 2011, Space Science Reviews 163, 329-369. [4] De Sanctis et al., 2017, Science 355, 719-722 [5] Pieters et al., 2018, Meteoritics and Planetary Science 53 (9), 1983-1998 [6] De Sanctis et al., 2019, MNRAS 482 (2), 2407–2421

Introduction One of the main topics of astrobiology research is the study of life’s limits in stressful environments. The study of organisms in extreme environments might give an indication about their potential adaptive plasticity, in the view of a climate change perspective, the terrestrial geological past and future scenarios, as well as extra-terrestrial habitats such as Mars’ surface. Lichens - with their excellent adaptive abilities - represents an extremely interesting case study. Several astrobiological studies involving lichens - that are symbiotic association between a fungus and an alga and/or acyanobacterium - proved the ability of these organisms to resist and thrive in extreme environments such as space and Mars’ surface simulated conditions [1, 2]. We have already tested the lichen species Xanthoria parietina (L.) Th. Fr. in simulated space conditions, that was able to survive and to reactivate after exposure [3]. X. parietina is a cosmopolitan foliose lichen that grows on barks and rocks [4]. This species shows high tolerance to air pollutants, heavy metals, and resistance to UV-radiation thanks to the shielding properties of the secondary metabolite parietin [5, 6]. Here we present a new study on the survival of X. parietina under simulated Mars conditions performed at the Mars Simulation Facility of the DLR Institute of Planetary Research in Berlin (Fig.1). Figure 1 - Mars Simulation Facility at DLR with the opened experiment chamber. Methods The aim of the study was to assess the survivability of Xanthoria parietina under simulated Mars conditions for 30 days [7, 8]. Inside the Mars simulation chamber, eight samples (Fig.2) were exposed to the simulated atmospheric conditions of Mars of which four were fully UV-irradiated with day-night cycles (FM, Full-Mars) and the other four kept in darkness (DM, Dark-Mars). A three-gas mixture of 95% CO2, 4% N2 and 1% O2 was used as best approximation of Mars-like atmospheric conditions, with a constant pressure of 600Pa. Temperature and humidity were subjected to day-night cycles, reaching during daytime 15°C and 0% RH, and during night -55°C and 100% RH (Fig.3) according to Martian thermophysical conditions at mid-latitudes. UV-radiation for FM samples was simulated using a Xenon UV-lamp (spectral range 200 nm – 2200 nm) that was automatically turned on for 16 h (day) and turned off for 8 h (night) daily. The total average radiation dose for FM was 2452.32 J/cm2 and the average instantaneous irradiance on the sample spots was 14,2 W/m2 [9]. Four other samples (Fig.2) were kept in control conditions during the experiment, at the constant temperature of 25°C, daily wetted and 12h dark and 12h light (ca. 50 μmol m-2 s-1 PAR photons). Several analyses were carried out to study all the samples before, during and after the exposure to the extreme Mars conditions. In detail, this experiment was performed aiming: to monitor the lichen vitality through chlorophyll a fluorescence (FV/FM) as photosynthetic efficiency parameter, carrying out in situ and after treatment analyses, to evaluate the oxidative stress due to the extreme conditions, highlighting eventual changes in the lichen carotenoids’ Raman signatures, to verify eventual modifications in the infrared features (peak shifting) in the lichen FTIR reflectance spectrum possibly related to UV-photodegradation effects, to highlight possible variations in the lichen ultrastructure through TEM analysis. Figure 2 - Xanthoria parietina samples ready for the experiment. First row (from above): full Mars samples, second row: dark Mars samples, third row: control samples. Figure 3 - Detail of the day-night cycles of the simulated Mars conditions (temperature, red thick line; humidity, blue thin line) and fluorescence variation values for both the treatments (FM and DM). Results The results showed significant differences between FM and DM photosynthetic efficiency parameter during exposure to Mars environment, exhibiting FV/FM values correlated with temperature and humidity day-night cycles (Fig.3). The FV/FM recovery values showed significant differences between the treatments too, highlighting that FM conditions caused stronger effects on fluorescence values. Additional analyses show possible changes in the Raman and FTIR spectra of the irradiated samples with several features involved. Overall, Xanthoria parietina was able to survive to FM conditions, and for this reason it may be considered a candidate for long exposure in space and evaluations on the photodegradability of parietin in extreme conditions. Reference [1] Onofri, S., de la Torre, R., de Vera, J. P., Ott, S., Zucconi, L., Selbmann, L., Scalzi, G., Venkateswaran, K. J., Rabbow, E., Sánchez Iñigo, F. J., and Horneck, G. (2012). Survival of rock-colonizing organisms after 1.5 years in outer space. Astrobiology, 12(5), 508-516. [2] De Vera, J. P., Möhlmann, D., Butina, F., Lorek, A., Wernecke, R., and Ott, S. (2010). Survival potential and photosynthetic activity of lichens under Mars-like conditions: a laboratory study. Astrobiology, 10(2), 215-227. [3] Lorenz, C., Bianchi, E., Benesperi, R., Loppi, S., Papini, A., Poggiali, G., & Brucato, J. R. (2022). Survival of Xanthoria parietina in simulated space conditions: vitality assessment and spectroscopic analysis. International Journal of Astrobiology, 1-17. [4] Nimis P.L., 2016. ITALIC - The Information System on Italian Lichens. Version 5.0. University of Trieste, Dept. of Biology, (http://dryades.units.it/italic), accessed on 2022, 05, 09. for all data contained in the taxon pages, including notes, descriptions, and ecological indicator values. [5] Silberstein, L., Siegel, B., Siegel, S., Mukhtar, A., and Galun, M. (1996). Comparative Studies on Xanthoria parietina, a Pollution Resistant Lichen, and Ramalina duriaei, a Sensitive Species. I. Effects of Air Pollution on Physiological Processes. The Lichenologist, 28:355-365. [6] Solhaug, K. A., and Gauslaa, Y. (1996). Parietin, a photoprotective secondary product of the lichen Xanthoria parietina. Oecologia, 108:412-418. [7] Lorek, A., and Koncz, A. (2013). Simulation and measurement of extraterrestrial conditions for experiments on habitability with respect to Mars. In Habitability of Other Planets and Satellites (pp. 145-162). Springer, Dordrecht. [8] De Vera, J. P., Schulze-Makuch, D., Khan, A., Lorek, A., Koncz, A., Möhlmann, D., and Spohn, T. (2014). Adaptation of an Antarctic lichen to Martian niche conditions can occur within 34 days. Planetary and Space Science, 98, 182-190. [9] Cockell, C. S., Catling, D. C., Davis, W. L., Snook, K., Kepner, R. L., Lee, P., and McKay, C. P. (2000). The ultraviolet environment of Mars: biological implications past, present, and future. Icarus, 146(2), 343-359.

Introduction: Near-Earth objects (NEOs), due to their proximity to our planet, represent one of the most accessible bodies in the whole Solar System. Their investigation can offer answers to several pressing questions in modern planetology (regarding, e.g., planetary formation, delivery of water and organics to the early Earth, and emergence of life). However, NEOs can also represent a risk for human civilization, since few of them can be potential impactors [1].The binary Didymos system: The binary NEO Didymos is composed of a main body (68503) Didymos and its satellite, later renamed Dimorphos. Recent studies estimate that nearly 15% of large NEOs (> 200 m) should be binaries [2]. At the moment, the most current explanation involves the reaccumulation of a body following a rotational disruption, probably as a result of the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect. However, other mechanisms are predicted for different sizes and populations of small bodies (capture, collision and tidal processes) [3].Binary NEOs can also be helpful to demonstrate the applicability of the most mature technique for impact mitigation, i.e. the kinetic impactor [4]. To this purpose, the NASA Double Asteroid Redirection Test (DART) has been approved to be the first demonstration of an hazard mitigation of an asteroid by using a kinetic impactor [5].The DART/LICIACube mission: The DART spacecraft, launched on November 23rd 2021, will impact Dimorphos, the smaller member of the Didymos binary asteroid system, on September 26th 2022. Hosted as a piggyback during the 15 months of DART interplanetary cruise there will also be LICIACube, the Light Italian Cubesat for Imaging of Asteroids [6], which is a 6U cubesat space mission supported by the Italian Space Agency (ASI). LICIACube will be released in the proximity of the target and will perform an autonomous fly-by of the Didymos system, probing the DART impact and reaching several scientific goals, such as: i) witness with its optical payloads (LUKE & LEIA, [6]) the impact of DART, ii) study the structure and evolution of the ejecta plume, and iii) acquire images of the event’s aftermath on the impacted hemisphere, as well as characterizing the non-impacted one.Ground-based characterization of the Didymos system prior to the impact: Data available in literature for the target of the DART/LICIACube mission, the binary NEO 65803 Didymos, is scarce. Only few spectra were taken during the latest observational windows in 2003 and 2019. The limited compositional data available for this NEO suggests a possible silicate composition [7], and an affinity with its best meteorite analogue, the L- and LL-ordinary chondrites [8]. A detailed spectral characterization in this case is crucial due to its binary nature, in order to disentangle the contribution of the primary from the secondary body and asses the heterogeneity of the surface composition in the light of the DART/LICIACube mission.A potential heterogeneity on Didymos: During the latest observational window in 2021 (the last before the DART impact) we obtained for the first time a complete rotational characterization of the system via visible spectroscopy. While the observations confirm an affinity with silicate material and ordinary chondrites, data analysis shows a subtle but persistent spectral slope variation, computed in this case between 0.5 and 0.7 µm. This slope variation is also confirmed by comparing our most recent data with spectra obtained during the previous 2003 and 2019 passages (see Fig. 1).Figure 1 – Comparison between a representative set of spectra collected during our observations in 2021, together with previously observed spectra of the Didymos system retrieved in literature. a) Spectrum #1 together with the one observed by J. De Leon in 2019 in red (private communication); b) Spectrum #5 together with one from [9] in green; right) spectrum #8 with one retrieved by [7] in cyan. Published originally in [10].Figure 2 – Comparison between three representative Didymos spectra observed at TNG during the 2021 observational window with their best meteorite analogue. Best analogue is represented by either L-, LL-ordinary chondrites or pure olivine and hypersthene spectra, the main components of L-/LL ordinary chondrites, suggesting that variability is probably related with different concentration of these minerals. Published originally in [10].Future work: New spectral characterization already scheduled for 2022 in the unexplored NIR range will be helpful to confirm these promising results. We will compare this new data with RGB-images obtained by LUKE camera on board of LICIACube, to look for potential heterogeneity of the surface. Moreover, we will take advantage of the unprecedented brightness of the system during the 2022 observational window (brighter than the last two decades, Vmag = 14.5) to further investigate the contribution of Dimorphos, constrain potential similarity/difference with respect to Didiymos, and assess eventual mineralogical changes induced to the system by DART impact. These observations will be the ideal benchmark also in light of the Hera mission [12], which will visit the system in 2026. Acknowledgments: This research was supported by the Italian Space Agency (ASI) within the LICIACube project (ASI-INAF agreement AC n. 2019-31-HH.0).References: [1] Perna D., et al., 2013, A&A Rev. 21, 65; [2] Margot, J. L et al. 2015, Ast. IV, 355; [3] Walsh, K. J. & Jacobson, S. A., Ast. IV, 454; [4] Cheng, A. F. et al. 2018, P&SS,157,104; [5] Rivkin A.S. et al., (2021) [6] Dotto E. et al., 2021, PSS, 199, 105185; [7] De Leon J., et al., 2010, A&A 517, A23; [8] Dunn, T. L., et al., 2013, Icarus, 222, 273; [9] Binzel, R.P. et al., 2004, Icarus, 170, 25; [10] Ieva, S. et al., 2022, PSJ, submitted. [11] Michel, P. et al., 2022, PSJ, submitted.

Laboratory simulations of the Martian conditions are essential in order to interpret results collected on Mars exploration missions. Among them, the study of the degradation and/or the evolution of possible organic biomarkers adsorbed on minerals is very important. The thin atmosphere of Mars allows ionizing radiations to reach the surface of the planet and drive the photochemical production of strong oxidants in the soil which possibly degrade the organics on the Mars´ surface1. However, traces of ancient life forms may be found in old mineral deposits preserved within protected environments recently accessible due to erosion or impacts. It is known that mid-UV radiation is among the main degradation agents on Mars2. Thus, inspection the stability and reactivity of possible biomarkers in the eolian-mobile layer and in the different fresh subsurface minerals exposed at the surface of Mars is important. Laboratory simulations of the harsh Martian conditions can evaluate the likelihood of preservation of potential biomarkers on different minerals on Mars. This provides a critical support to rover missions on Mars, helping to select the most appropriate minerals to find organic molecules and therefore, possible biomarkers. In this work, the interaction and stability of L-histidine in saponite are studied. The saponite mineral was chosen because is a common product of low-temperature reaction between water and the mafic minerals on Mars. In addition, saponite in old cold basaltic crust is favourable for microbial life.3 L-histidine, an α- amino acid used in the biosynthesis of proteins, was chosen as biomarker because it is very diagnostic of life. Moreover, it presents different protonation states depending on the pH, which might result in different interaction with the mineral at different pHs. The samples were prepared using the equilibrium adsorption method. In particular, pure synthetic saponite was put in contact with different solutions of L-histidine at pH 2.7 and 9.6, in order to investigate the effect of acidic or alkaline conditions on the adsorption process. The suspensions were kept for 24 hours on rotation to reach the equilibrium state during molecular adsorption, and then they were dried in an oven at 40◦C. The samples were analyzed by X-Ray Diffraction to understand if any intercalation of L-histidine in the negatively-charged interlayer sites of saponite occurs at acidic pH. Further characterization of molecule-mineral interactions was carried out by Transmittance and Diffuse Reflectance InfraRed Fourier Transform Spectroscopy. Finally, the samples were processed under Martian-like UV irradiation conditions using an experimental setup which allows to monitor the degradation kinetics in situ by infrared spectroscopy analysis during UV irradiation. These experiments allowed us to investigate the catalytic/protective behaviour of saponite towards L-hystidine in different pH conditions, and obtain the degradation cross section of L-histidine adsorbed on saponite compared to the pure molecule, along with the half-lifetime of degradation under Martian UV flux. References 1Quinn, R. C.; Martucci, H. F. H.; Miller, S. R.; Bryson, C. E. Perchlorate Radiolysis on Mars and the Origin of Martian Soil Reactivity. Astrobiology 2013, 13 (6), 515–520. 2Fornaro, T.; Steele, A.; Brucato, J. R. Catalytic/Protective Properties of Martian Minerals and Implications for Possible Origin of Life on Mars. Life 2018, 8. 3Y. Sueoka, S. Yamashita, M. Kouduka, Y. Suzuki, Deep Microbial Colonization in Saponite-Bearing Fractures in Aged Basaltic Crust: Implications for Subsurface Life on Mars, Frontiers in Microbiology. 10 (2019).

Polycyclic aromatic hydrocarbons (PAHs) represent ~20% of cosmically available carbon [1, 2]. The further photochemical evolution of PAHs on planetary surfaces is of interest to early Earth origin-of-life studies and Mars origin-of-life speculations. Much of the literature has focused on small molecules contained in meteorites, such as amino acids and nucleic acid bases, and their potential as a carbon source for prebiotic chemistry on early Earth. However, 75% of extraterrestrial organic matter in meteorites is in aromatic form [3], and is more likely to survive the journey to a planetary surface, during which much of the small molecules can be destroyed. These stable carbon compounds could later be broken down into smaller, more biologically relevant molecules by photocatalysis on clay mineral surfaces in the ultraviolet radiation regime of early Earth and Mars. Here we experimentally test whether PAHs degrade when adsorbed to nontronite clay and exposed to ultraviolet radiation. Experiments were performed at the INAF Observatory of Arcetri and in the PALLAS chamber at Utrecht University and were monitored with in-situ diffuse reflectance infrared spectrometry (DRIFTS) measurements. PAHs and any degradation products were extracted post-irradiation and analyzed with nuclear magnetic resonance (NMR). [1] Allamandola, L. J., Tielens, A. G. G. M., & Barker, J. R. (1989). The Astrophysical Journal Supplement Series, 71, 733-775. [2] Puget, J. L., & Léger, A. (1989). Annual review of astronomy and astrophysics, 27(1), 161-198. [3] Sephton, M. A. (2002). Natural product reports, 19(3), 292-311.

Instrument overviewThe Light Italian Cubesat for Imaging of Asteroids (LICIACube) [1] is part of the NASA Double Asteroid Redirection Test (DART) [2], the first mission aiming to demonstrate the applicability of the kinetic impactor method for planetary defense. The mission was launched on 24 November 2021 to perform the impact experiment on Dimorphos, the small secondary of the binary asteroid (65803) Didymos, on September 26, 2022. The 6U LICIACube, stored as a piggyback of DART spacecraft, is the first Italian mission operating in deep space managed by the Italian Space Agency (ASI) that will witness the effects of DART impact on Dimorphos. The Italian cubesat will perform an autonomous fly-by of the binary system with several scientific objectives: (i) to directly witness the impact of DART spacecraft on Dimorphos surface; (ii) to study the ejecta plume over its evolution in time and under varied phase angles in order to estimate the properties of the plume and the evolution of its grain distribution; (iii) to study the impact site with sufficient resolution to allow the measurements of size, color and morphology of the artificial crater formed in the aftermath; (iv) to perform observations of the non-impacted hemisphere to increase accuracy in the determination of the target’s shape and volume and for overall investigation of the surface. To fulfill such key objectives, LICIACube is carrying a suite of cameras composed by the LICIACube Explorer Imaging for Asteroid (LEIA), a narrow FoV camera, and LUKE, a Gecko imager provided by SCS space company. The 70.55 mm focal length of LUKE is designed to work in focus between 400 m to infinity. FoV is ±5° and IFoV 78 μrad/px with a spatial scale about 4 m/px at 51 km. LUKE is equipped with a front illuminated CMOS detector (ams CMV2000), the pixel pitch is 5.5 microns and images will be 1088x2048 pixels. It is an RGB camera with a Bayer pattern filter. LICIACube will be released by DART about 10 days before the impact and it will autonomously fly to the target, reaching a minimum distance of about 51 km (Closest Approach). During the fly-by, both LEIA and LUKE cameras will acquire 228 RGB image (for a simulated example see Figure 1) of the impacted and non-impacted target sides with a resolution ranging from 71 m/px down to 4.3 m/px.Fig 1 Original frame and zoom-in of analog image of Didymos-Dimorphos system, simulated using the shape models of asteroids Ryugu and Itokawa, as observed by LUKE. Expected scientific analysisSeveral activities in support of the scientific analysis are ongoing and more will be done once data will be downloaded [3]. Four main studies are linked with LUKE science: (i) laboratory support to data interpretation, (ii) multivariate statistical analysis of LUKE data, (iii) photometric phase curve analysis, and (iv) study of the plume evolution.The support of laboratory analyses will be continuous across all the LICIACube mission phases to support the interpretation of the data collected by the LICIACube payload. Main activities will concern RGB measurements with LUKE-like RGB cameras and analysis of LUKE RGB bands spectral response with existing and new laboratory spectroscopic measurements in LUKE wavelength range. In detail we will proceed with: 1) the creation of a dedicated database to support the investigation on surface composition; 2) the study of surface processes able to modify the appearance of Didymos and Dimorphos surfaces.Moreover, by using multi-color images acquired by LUKE we will analyze the features on Dimorphos and Didymos surfaces both from a geomorphological and a compositional perspective. By applying the G-Mode method we will search for possible heterogeneities/variegations on the surface characterizing regions with the same spectral behavior. This analysis is therefore fundamental to infer the formation and the evolution of this binary system. Indeed, binary asteroids' possible compositional differences are still poorly investigated due to the difficulties in ground-based observation and the absence of dedicated space missions.In addition, during about 10 days in the nominal operation schedule of LICIACube, LUKE is expected to capture images of the Didymos-Dimorphos system ranging from 42 to 120 degrees of phase angle and down to about 51 km. Didymos will become resolved by 4 pixels about 7 minutes before the impact, while Dimorphos will reach the same spatial resolution only 42 seconds after. The photometric phase curve will reveal some scattering properties of the granular surface medium. Within this phase angle coverage, the surface texture, particles’ irregularities, multiple scattering, and multi-scale roughness are the dominant properties.LUKE data will help improve our knowledge on asteroid binary systems in particular on their origin and evolution. Expected results promise to significantly advance our understanding of these small rocky bodies in combination with the other data obtained by the mission both from the spacecraft and from ground observations.AcknowledgementsThe LICIACube team acknowledges financial support from Agenzia Spaziale Italiana (ASI, contract No. 2019-31-HH.0 CUP F84I190012600). This work utilizes spectra downloaded by NASA RELAB facility at Brown University. All the authors have contributed to the present work. The entire LICIACube Team made this paper possible. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.References[1] Dotto et al. 2021, PSS, 199, 105185[2] Rivkin et al. 2021, PSJ, 2, 5, 173[3] Poggiali et al. 2022, PSJ, submitted

Interpretation of spectral data acquired remotely and/or in situ from other planets requires an exhaustive database taking into account well-characterized spectra. Silicate glasses are one of the main constituents of volcanic rocks and a deep knowledge of their spectral response is fundamental to characterize volcanic terrains that we can observe on other planets.We will show a study concerning spectroscopy properties of silicate glasses, which were synthesized at the Petro-Volcanology Laboratory of the University of Perugia. This study has the main objective to simulate and characterize putative compositions of lavas present on the Northern Volcanic Province of Mercury.Glasses were synthesized mixing pure oxides and melting them at high temperatures. Once produced, glasses were partly crushed to powders in order to obtain different grain size classes and distributions. Furthermore, they were partly embedded as bulk fragments in epoxy and irradiated by laser ablation at different powers to simulate space weathering effects on Mercury.The spectroscopic characterization of the samples was performed at the INAF-Astrophysical Observatory of Arcetri, Firenze, where mid-IR biconical diffuse reflectance FTIR spectra in the range 7-15 µm range were acquired on samples characterized by different granulometry. Spectroscopic measurements were performed first on 7 different homogeneous granulometric classes (ranging from 25 to 500 µm), then on six heterogeneous granulometric classes presenting gaussian distributions with varying values of average granulometry and standard deviation. Finally, spectra were acquired on slabs of glasses, which were previously irradiated by laser ablation simulating both weathered surface and re-deposited fine material after meteoritic impacts.The results showed that spectroscopic features depend on the grain sizes, and in particular they are strongly influenced by presence of fine materials in the heterogeneous samples. Such information was used to retrieve detailed granulometrical data of the bulk samples which were covered by ablated and redeposited particles.The study shows that experimental petrology is indeed a powerful tool to obtain planetary analogues of any terrestrial and planet product. The spectral characterization and space weathering simulation in the laboratory represent useful techniques to develop instrumental and analytical knowledge for space and planetary exploration. This study was performed on a specific Mercurian product, but in general this kind of approach can be preparatory to design future exploration missions of any planetary/asteroidal site in particular.

Light Italian Cubesat for Imaging of Asteroids (LICIACube) is an Italian mission managed by the Italian Space Agency (ASI) and part of the NASA Double Asteroid Redirection Test (DART) planetary defense mission. Its main goals are to document the effects of the DART impact on Dimorphos, the secondary member of the (65803) Didymos binary asteroid system, characterizing the shape of the target body and performing dedicated scientific investigations on it. Within this framework, the mission Science Operations Center will be managed by the Space Science Data Center (ASI-SSDC), which will have the responsibility of processing, archiving, and disseminating the data acquired by the two LICIACube onboard cameras. In order to better accomplish this task, SSDC also plans to use and modify its scientific webtool Multi-purpose Advanced Tool for Instruments for the solar system Exploration (MATISSE), making it the primary tool for the LICIACube data analysis, thanks to its advanced capabilities for searching and visualizing data, particularly useful for the irregular shapes common to several small bodies.

The Light Italian Cubesat for Imaging of Asteroids (LICIACube) is part of the NASA Double Asteroid Redirection Test (DART), the first mission aiming to demonstrate the applicability of the kinetic impactor method for planetary defense. The mission was launched on 2021 November 24 to perform the impact experiment on Dimorphos, the small secondary of the binary asteroid (65803) Didymos. The 6U LICIACube, stored as a piggyback of the DART spacecraft, is the first Italian mission operating in deep space managed by the Italian Space Agency that will witness the effects of the DART impact on Dimorphos. On board LICIACube, there is a suite of cameras that will perform imaging of Didymos and Dimorphos to investigate the DART impact effects and study the binary system. Among them, the LICIACube Unit Key Explorer (LUKE), a wide-angle camera coupled to an RGB Bayer pattern filter, will be pivotal to constrain the surface composition and heterogeneity of the binary system due to differences in surface properties linked with possible space weathering effects and/or the presence of exogenous material. Multiband photometric analysis of LUKE data and laboratory experiments in support of data interpretation will provide new insights on the binary asteroid nature and evolution. Moreover, photometric phase curve analysis will reveal the scattering properties of the granular surface medium providing important constraints for the microphysical properties of the Didymos–Dimorphos system. In this work, we will present the state of the art of the LUKE scientific activities with an overview of the instrument setup, science operations, and expected results.

The DART spacecraft will impact Dimorphos (the secondary body of the Didymos binary asteroid) to test the kinetic impactor deflection method against possibly hazardous near-Earth asteroids. The DART impact ejecta plume, and possibly the impact crater, will be imaged by the LICIACube spacecraft, hosted as a piggyback and released by DART just before the impact, and then, several years later, by the Hera probe. To exploit the wealth of data obtained and understand the physics of the whole impact experiment, it is of paramount importance to properly model the dynamics of the binary system pre- and postimpact and the dynamics of the particles ejected from the impact crater. A model was developed to simulate the evolution of the ejecta particles created during the impact in order to first interpret the LICIACube images and then test the survival of particles on long intervals of time that might be detected by the Hera mission either as individual bodies or as parts of rings. The dynamical evolution of the particles is simulated over different timescales to highlight the most important perturbations and their relative importance. The ejecta dynamics turns out to be highly chaotic due to repeated close encounters with the two asteroids. However, we find that some ejecta survive in the binary orbital environment for timescales comparable to the Hera arrival time. The effects of the particles reimpacting against either one of the components is also analyzed to estimate the amount of momentum transfer to the target bodies.

Abstract We present laboratory activities of preparation, characterization, and UV irradiation processing of Mars soil analogues, which are key to support both in situ exploration and sample return missions devoted to detection of molecular biosignatures on Mars. In detail we prepared analog mineral samples relevant to the landing sites of past, present and future Mars exploration missions, such as Gale Crater, Jezero Crater, and Oxia Planum. We doped these samples with a large variety of organic molecules (both biotic and prebiotic molecules) like amino acids, nucleotides, monosaccharides, aldehydes, lipids. We investigated molecular photostability under UV irradiation by monitoring in situ possible modifications of infrared spectroscopic features. These investigations provide pivotal information for ground analysis carried out by rovers on Mars. Introduction Laboratory simulations of Mars are key to support the scientific activity and technology development of life detection instruments on board present and upcoming rover missions such as Mars2020 Perseverance [1] and ExoMars2022 Rosalind Franklin [2]. Studies about the stability of organic molecules in a Martian-like environment allow us to explore the conditions for the preservation of molecular biosignatures and develop models for their degradation in the Martian geological record. A systematic study of the effects of UV radiation on a variety of molecule-mineral complexes mimicking Martian soil can be key for the selection of the most interesting samples to analyse in situ or/and collect for sample return. Testing the sensitivity of different techniques for detection of the diagnostic features of molecular biosignatures embedded into mineral matrices as a function of the molecular concentration helps the choice, design and operation of flight instruments, as well as the interpretation of data collected on the ground during mission operative periods. Methods Experimental analyses were conducted in the Astrobiology Laboratory at INAF-Astrophysical Observatory of Arcetri (Firenze, Italy). Laboratory activities pertain to: (i) synthesis of Mars soil analogues doped with organic compounds that are considered potential molecular biosignatures; (ii) UV-irradiation processing of the Mars soil analogues under Martian-like conditions; and (iii) spectroscopic characterization of the Mars soil analogues. Results Such studies have shown to be very informative in identifying mineral deposits most suitable for preservation of organic compounds, while highlighting the complementarity of different techniques for biomarkers detection, which is critical for ensuring the success of space missions devoted to the search for signs of life on Mars. We will present a series of laboratory results on molecular degradation caused by UV on Mars and possible application to detection of organics by Martian rovers [3,4,5,6]. In detail, we investigated the photostability of several amino acids like glycine, alanine, methionine, valine, tryptophan, phenylalanine, glutamic acid, prebiotic molecules like urea, deoxyribose and glycolaldehyde, and biomarkers like nucleotides and phytane adsorbed on relevant Martian analogs. We monitored the degradation of these molecule-mineral complexes through in situ spectroscopic analysis, investigating the reflectance properties of the samples in the NIR/MIR spectral region. Such spectroscopic characterization of molecular alteration products provides support for two upcoming robotic missions to Mars that will employ NIR spectroscopy to look for molecular biosignatures, through the instruments SuperCam on board Mars 2020, ISEM, Ma_MISS and MicrOmega on board ExoMars 2022. Acknowledgements This research was supported by the Italian Space Agency (ASI) grant agreement ExoMars n. 2017-48-H.0. References [1] Farley K. A. et al. (2020) Space Sci. Rev. 216, 142. [2] Vago, J. L. et al. (2017) Astrobiology 6, 309–347. [3] Fornaro T. et al. (2013) Icarus 226, 1068–1085. [4] Fornaro T. et al. (2018) Icarus 313, 38-60. [5] Fornaro T. et al. (2020) Front. Astron. Space Sci. 7:539289. [6] Poggiali G. et al. (2020) Front. Astron. Space Sci. 7:18.

Summary Ceres is the largest object in the Solar System main belt. Clearly, Ceres experienced extensive water-related processes and geochemical differentiation and nowadays it is a body with a complex geological and chemical history [1]. Its surface is characterized by dark materials, phyllosilicates, ammonium-bearing minerals, carbonates, water ice, and salts. In addition to a global presence of carbon bearing chemistry, local concentration of aliphatic organics has been detected by Dawn [2]. In this context, we have started a series of laboratory spectroscopy measurements targeted to study the physicochemical interactions between organic material and minerals possibly present on Ceres. The goal is to understand the transformations induced on these samples by ultraviolet radiation, neutral atoms, and fast ions, under experimental conditions that simulate the environment of Ceres. The spectroscopic data obtained in laboratory experiments allow, through the comparison with the observations of the VIR spectrometer aboard the Dawn mission, to clarify the nature and origin of organic material identified on Ceres. Introduction Organic material in the minor bodies of the Solar System is an important component to understand planetary evolution and, eventually, the origin of life. Nevertheless, our knowledge on the subject is still limited. Recently the Dawn mission, thanks to the data collected by the Italian instrument VIR [3], showed clear evidence of a high amount of aliphatic organic material on the surface of Ceres [4, 5, 6] (Fig 1). This evidence has raised new questions about the origin and preservation of this material, especially when considering its high estimated abundance and the mineralogical context. Fig 1 Ceres spectra of the organic-rich area in Ernutet crater (label “Organics”); of a background organic-poor area from a region southeast of Ernutet (label “Background”); and of Occator bright material (label “Carbonate”) [4]. In order to understand the organic chemical species and in particular their abundance on Ceres, laboratory studies were performed [7]. The importance of having a direct comparison between laboratory and remote sensing data can provide a further investigation clues to shed light on the origin and evolution of Ceres. Through this project, we intend to study, through dedicated experiments, the interaction between minerals, water, and organic concerning the environmental conditions of Ceres. Making a synergistic use of complementary and indispensable skills present within INAF (Italian National Institute of Astrophysics) laboratories we investigated a complex issue such as that concerning the origin and preservation of organic molecules on planetary surfaces. Within INAF, complementary and unique realities coexist which, thanks to joint and coordinated work, can give a new interpretation of the physical-chemical processes active on Ceres. Project development and results In this study, we prepare mixtures of materials resembling the Ceres surface composition [8, 9] adding organic molecules in order to: (i) understand how organic molecules behave and eventually degrade on Ceres, in particular, how aliphatic molecules degrade by energetic processing with fast ions (keV-MeV) and UV photons [10, 11]. Moreover, the physico-chemical properties of the materials exposed to a flux of neutral atoms are investigated [12, 13]. (ii) evaluate the interaction between ammoniated minerals and simple organic molecules that may lead to the synthesis of complex compounds. In the presence of ultraviolet (UV) radiation, these minerals present on the surface of Ceres can show photocatalytic effects accelerating the photo-reactions, which generally destroy the original organic molecule and in the synthesis of new complex organic molecules [14]. (iii) evaluate the role of minerals in the protection or degradation of organic compounds. Some studies indicated a fundamental role of clays in the catalysis and preservation of organic materials [15]. Ceres is rich in clays and other hydrated minerals, making the interactions with the observed organics of particular interest. The project is carried out by several INAF institutes and laboratories. In detail: INAF-IAPS Istituto di Astrofisica e Planetologia Spaziali prepared the analog mineral mixtures taking into account the compositional information gained by VIR observations. INAF - Osservatorio Astrofisico di Arcetri subsequently doped the mixture with several organic investigating UV photostability in Ceres analog conditions and the influence of temperature. INAF -Osservatorio Astronomico di Capodimonte studied irradiation with atoms and temperature effect while INAF - Osservatorio Astrofisico di Catania performed irradiation with fast ions. Finally, results of laboratory measurements were compared with data obtained by VIR instrument onboard Dawn mission. AcknowledgementsThis work is support by INAF Main Stream programme, grant 1.05.01.86.08 Evoluzione ed alterazione del materiale organico su Cerere (ref. Maria Cristina De Sanctis). References [1] De Sanctis et al., 2016, Nature 536, 54–57 [2] Marchi et al., Nature Astr., 2019 [3] De Sanctis et al., 2011, Space Science Reviews 163, 329-369. [4] De Sanctis et al., science 2017 355, 719 [5] Pieters et al., 2018, Meteoritics and Planetary Science 53 (9), 1983-1998 [6] De Sanctis et al., 2019, 482 (2), 2407–2421 [7] Vinogradoff et al., 2021 [8] Ferrari et al., 2019, Icarus 321, 522-530 [9]De Angelis et al., 2021 JGR Planets doi: 10.1029/2020JE006696 [10] Baratta et al. 2002, A&A, 384, 343-349 [11] Brucato et al. 2006, A&A, 455, 395-399 [12] Mennella et al. 2003, ApJ, 587, 727-738 [13] Palumbo et al 2004, Ad. Sp. Res., 33, 49-56 [14] Fornaro et al. 2013, Icarus, 226(1), 1068–1085 [15] Fornaro et al 2018, Astrobiology, 18, 989-1007

Introduction: Millimeter and centimeter observations are discovering an increasing number of interstellar complex organic molecules (iCOMs) in a large variety of star-forming sites from the earliest stages of star formation to protoplanetary disks. To correctly interpret the distribution and abundances of iCOMs observed along the formation process of a Sun-like star (i.e. in pre-stellar dense cores1,2, hot corinos around protostars3,4, in the associated jets and outflows5,6, and protoplanetary disks7), we need to first comprehend their formation processes and the mechanism responsible for their release in gas-phase. In this context, it is pivotal to understand the influence of the solid phase interactions between iCOMs and grain surface in the thermal desorption process and the subsequent presence of molecular species in the gas phase. Thermal desorption can be characterized through laboratory experiments using interstellar ice analogs deposited on grains similar to interstellar ones deriving important parameters such as the desorption temperatures and energies. Up to now, temperature-programmed desorption (TPD) experiments have been carried out mainly from graphite and amorphous water ice surfaces8,9,10,11. As far as we know, TPD experiments from grain surfaces are lacking in the literature, although mineral matrices can selectively adsorb, protect, and allow the iCOMs concentration on their surface. Molecules can diffuse inside the grains and so, the presence of grains can influence the desorption and release of the iCOMs in the gas phase. Laboratory measurements: We report our new recently published laboratory results12 on TPD experiments of astrophysical relevant ice mixtures of water, acetonitrile (CH3CN), and acetaldehyde (CH3COH) from micrometric grains of silicate olivine ((Mg,Fe)2SiO4) used as interstellar dust analog on which the icy mixtures were condensed at 17 K inside the ultra-high vacuum (UHV) chamber (P~6.68 × 10-10 mbar). The ice mixtures condensed on olivine dust were heated at a constant rate, so the molecules diffused and desorbed from the dusty sample, and in situ TPD analysis was made. Results: We found that in the presence of grains, only a fraction of acetaldehyde and acetonitrile desorbs at about 100 K and 120 K respectively, while 40% of the molecules are retained by fluffy grains of the order of 100 μm up to temperatures of 200 K. In contrast with the typical assumption that all molecules are desorbed in regions with temperatures higher than 100 K, this result implies that about 40% of the molecules can survive on the grains enabling the delivery of volatiles towards regions with temperatures as high as 200 K. This may be important in protoplanetary disks where the submicrometric interstellar grains begin to agglomerate into fluffy grains of hundreds of microns. The diffusion of molecules on the silicate surface is a valuable process enabling the permanence of the ices in the inner part of the disk. This implies that O-rich and N-rich volatiles ice can survive up to ∼ 200 K, broadening the snowlines of O- and N-bearing molecules, such as CH3CN and CH3COH. The presence of dust grains in the protoplanetary disk can therefore determine the approach of the snowlines towards the star and allow the presence of water and volatile species in Earth-like planets forming region. These studies offer a necessary support to interpret observational data and may help our understanding of iCOMs formation providing an estimate of the fraction of molecules released at various temperatures. G. A. Blake, E. C. Sutton, C.R. Masson, T.G. Phillips, ApJ. 1987, 315 E. Herbst & E. F. van Dishoeck, ARA&A. 2009, 47 S. Cazaux, A. G. G. M. Tielens, C. Ceccarelli et al., ApJ. 2003, 593 C. Ceccarelli, P. Caselli, E. Herbst, A. G. G. M. Tielens & E. Caux, Protostars and Planets V. 2007, 47 R. Bachiller, & M. Pérez Gutiérrez, ApJ. 1997, 48 C. Codella, B. Lefloch, C. Ceccarelli et al., A&A. 2010, 518 J. Lee, S. Lee, G. Baek et al., Nature Astronomy. 2019, 3 M. P. Collings, M. A. Anderson, R. Chen et al., MNRAS. 2004, 354 T. Hama, N. Watanabe, A. Kouchi & M. Yokoyama, ApJL. 2011, 738 J. Shi, G. A. Grieves & T. M. Orlando, ApJ. 2015, 804 H. Chaabouni, S. Diana, T. Nguyen & F. Dulieu, A&A. 2018, 612 M. A. Corazzi, J. R. Brucato, G. Poggiali, L. Podio, D. Fedele & C. Codella, accepted on ApJ. 2021

One of the main topics of astrobiology is the study of life limits in stressful environments. This field of research has the aim to understand the physiological and biochemical effects on unprotected biological samples in extreme conditions, such as space. Moreover, these studies provide indications about organisms’ adaptive plasticity under a climate change perspective, the terrestrial geological past and future scenarios, as well as extra-terrestrial habitats as Mars surface. The biological specimen chosen for this study was Xanthoria parietina (L.) Th. Fr. It is a widespread foliose lichen growing on bark and rocks which has a broad spectrum of tolerance to air pollutants such as NOX and heavy metals, and resistance to UV-radiation because of the screening properties provided by the secondary metabolism product parietin. In this study we evaluated the ability of this lichen specie to survive under simulated UV space radiation in two different extreme environments i.e., in N2 atmosphere (N2) and in vacuum (100~10-2 Pa) (VAC). Thalli of X. parietina were randomly collected in a remote area of Tuscany, Italy in June and July 2020. Thalli were dehydrated for 24 h at room temperature (25°C) and stored at -18°C until treatment. Three days before the treatment, thalli were allowed to recover their normal metabolic conditions in a growth chamber at 25 °C and 70 μmol m-2 s-1 PAR photons. Overnight, thalli were covered with a black cotton cloth and kept moistened by spraying with distilled water. The simulated UV space radiation was produced using a Xe-enhanced UV lamp with a sun-like emission spectrum (wavelength range 185-2000 nm). The aforementioned atmospheric conditions (N2 and VAC) were chosen to set up an extreme and dehydrating environment for the lichen. The total absorbed UV radiation dose was 1.34 MJ m-2 for each exposed sample. During the irradiation, the IR reflectance spectrum of the lichen was monitored in situ with infrared spectroscopy to assess changes in spectral bands. The efficiency of the photosynthetic apparatus was assessed as indicator of vitality, and was expressed in terms of chlorophyll a fluorescence (FV/FM) and Normalized Difference Vegetation Index (NDVI). The examination of X. parietina recovery through eco-physiological analysis revealed the capacity of this lichen species to survive in extreme conditions such as those simulated in this investigation. It has been highlighted the significant difference between treatments about the photosynthetic efficiency parameters recovery trends, finding that UV-radiation in vacuum produces more intense effects on FV/FM values. After 72h, UV N2 fluorescence mean values recovered up to 93% of the starting ones, while UV VAC fluorescence recovered up to 45% of the pre-exposure values. The IR analysis revealed several spectral band changes in the fingerprint region. The most visible variation was the 5200 cm-1 water band, disappearing in the overtone region. This analysis suggests that the disappearance of H2O band after treatment is strictly linked to the thalli dehydration due to the atmospheric simulated conditions represented by N2 insufflation and high vacuum application. Nevertheless, X. parietina was able to survive to UV-radiation in N2 atmosphere and in vacuum, and for this reason it may be considered a candidate for further evaluations on its survival capacity in extreme conditions.

Introduction Astrobiology is an interdisciplinary field covered by only a few CubeSat missions so far. Moreover, no CubeSat mission has ever mounted miniaturized technology for the purpose of searching for molecular evidences of life in space. AstroBio CubeSat (ABCS) is a 3U CubeSat selected by the European Space Agency (ESA) to be launched in spring 2022 with the Vega C maiden flight, as piggy back passenger of the ASI LARES2 mission. ABCS will host a payload assembly based on Lab-on-Chip (LoC) technology for biomarkers detection and will be deployed along a circular orbit with altitude of about 5900 km and inclination of 7°, therefore crossing the inner Van Allen belt where the radiation flux is close to its maximum. Due to the harsh environment, ABCS payload and subsystems will be likely exposed to damages and degradations of electronics and performances, thus the payload assembly and the operational architecture were designed to be as much dependable as possible. This approach should constitute the first step to implement a mature technology with the aim to check the stability of chemicals and biomolecules involved in space experiments. This work reports an overview of ABCS architecture and the approach chosen for its operational design. ABCS Architecture ABCS objective is to test in space an automatic in-situ multiparameter LoC [1], which exploits luminol injection and enzymatic bio-mimicking assays on a functionalized 3D wax-printed origami. Luminol will be transported by capillarity to reaction sites with immobilized biomolecules targets where the reactions will trigger chemiluminescence, detected by means of hydrogenated amorphous silicon (a-Si:H) photodiodes deposited on a borosilicate glass substrate and connected to a photocurrent readout board [2]. The described payload consists in an experiment board hosting the LoC and a support board containing peristaltic pumps for luminol injection, drivers for pumps, radiation field effect transistors (RADFETs) and pressure/temperature sensors. The LoC architecture allows to repeat the experiment up to six times. In addition to RADFETs, ABCS mounts an ancillary radiation dose sensor (ARDS), developed by Thales Alenia Space, with the aim to assess the radiation effects. The ARDS is able to measure different amounts of current, until its failure, depending on the dose acquired. To mitigate the effects of the expected very high flux of charged particles, an extra tungsten layer shielding was mounted on each side panel and all the main subsystems (experiment and support board, batteries and EPS board, on-board computer (OBC), telemetry, tracking and control board), were placed inside a 5 mm thick aluminium box. At the same time, to keep the temperature range (from 4°C to 20°C) and operative pressure (about 1 atm) required to allow the LoC capillarity effect and to prevent reagents degradation, the box was sealed and a thermal control system, composed by a multi-layer insulation and an active heather mounted inside the box, was implemented. ABCS Mission Design ABCS will be deployed in an approximately circular orbit at about 5900 km altitude and 70° of inclination, spending a significant amount of the orbital period within the inner Van Allen belt, very close to its radiation peak point. ABCS ground operations will be mainly performed from the School of Aerospace Engineering (SIA) Ground Station. Simulations show that SIA will have access to ABCS 4 times a day, with an average duration of about 65 minutes. For this reason, a network of radioamateurs and third part ground stations will be involved for supporting the collection of the telemetry and science data packages and possibly uplink commands. ABCS Operations The assumption we made is that ABCS should be able to perform the payload operations in a completely autonomous manner. As we know, radiation flux will most likely induce several errors on electronics and performances, causing potential mission failure due to the fact that payload operations may not start because the OBC fails to send the command to start the experiment. A possible way to reduce failure is to perform ABCS experiments where the proton flux is lower. Simulations shows that this happens when ABCS is at polar latitudes, namely outside the range [-60°; 60°]. For this reason, the payload operations, based on redundant checks and triggers, were implemented accordingly. The purpose is to automatically determine if ABCS is at a latitude useful to perform the experiments and verifying this condition by means of multiple triggers, time or position based. Each trigger is used for scheduling purposes only if the ones with higher priority are unreliable. If all the triggers are not reliable, payload operations are forced to begin, as it is better to perform eventually degraded payload operations rather than performing no payload operations at all. Conclusions ABCS is required to operate in an extremely harsh environment where radiation fluxes are likely to degrade the electronic devices. Operations should be scheduled in order to reduce the time needed to perform all the experiments. The chosen approach will lead ABCS to complete the payload operations in three orbital periods, reducing the total ionizing dose absorbed and guaranteeing the higher system reliability. Acknowledgments ABCS AstroBio-CubeSat is supported by ASI - Italian Space Agency ASI/INAF Agreement n. 2019-30-HH.0. References [1] Iannascoli, L. et al. 2020, "Astrobio cubesat: Enabling technologies for astrobiology research in space", Proceedings of the International Astronautical Congress, IAC. [2] Mirasoli M, et al. 2014. Multiwell cartridge with integrated array of amorphous silicon photosensors for chemiluminescence detection: development, characterization and comparison with cooled-CCD luminograph. Anal Bioanal Chem. Sep;406(23):5645-56.

The Origins, Spectral Interpretation, Resource Identification, and Security Regolith Explorer(OSIRISREx) mission observed the The Origins, Spectral Interpretation, Resource Identification, and Security‐Regolith Explorer (OSIRIS‐REx) mission observed the Moon during the spacecraft's Earth gravity assist in 2017. From the spacecraft view, the lunar phase was 42°, and the in‐view hemisphere was dominated by anorthositic highlands terrain. Lunar spectra obtained by the OSIRIS‐REx Visible and InfraRed Spectrometer show evidence of several candidate absorption features. We observe the 2.8‐μm hydration band, confirming the spectral results from other missions, but detected in full‐disk spectra. We also tentatively identify weak spectral features near 0.9 and 1.3 μm, consistent with lunar regolith containing a mixture of plagioclase and orthopyroxene minerals, as expected for highlands terrain.

Millimeter and centimeter observations are discovering an increasing number of interstellar complex organic molecules (iCOMs) in a large variety of star forming sites, from the earliest stages of star formation to protoplanetary disks and in comets. In this context it is pivotal to understand how the solid phase interactions between iCOMs and grain surfaces influence the thermal desorption process and, therefore, the presence of molecular species in the gas phase. In laboratory, it is possible to simulate the thermal desorption process deriving important parameters such as the desorption temperatures and energies. We report new laboratory results on temperature-programmed desorption (TPD) from olivine dust of astrophysical relevant ice mixtures of water, acetonitrile, and acetaldehyde. We found that in the presence of grains, only a fraction of acetaldehyde and acetonitrile desorbs at about 100 K and 120 K respectively, while 40% of the molecules are retained by fluffy grains of the order of 100 {\mu}m up to temperatures of 190-210 K. In contrast with the typical assumption that all molecules are desorbed in regions with temperatures higher than 100 K, this result implies that about 40% of the molecules can survive on the grains enabling the delivery of volatiles towards regions with temperatures as high as 200 K and shifting inwards the position of the snowlines in protoplanetary disks. These studies offer a necessary support to interpret observational data and may help our understanding of iCOMs formation providing an estimate of the fraction of molecules released at various temperatures., Comment: Accepted for Publication on Astrophysical Journal

Using data acquired by the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer) mission, we investigate spectral properties of craters on the near-Earth asteroid (101955) Bennu. We compare Bennu's craters with its global average by means of four spectral parameters: (a) minimum position of the band at 2.7 μm, (b) depth of the hydrated phyllosilicate absorption band at 2.7 μm, (c) normalized spectral slope from 0.55 to 2.0 μm, and (d) reflectance factor at 0.55 μm. We examine 45 craters using spectral data obtained under various observing conditions. For 20 craters, we find a shortward shift of the 2.7-μm band minimum relative to the global 2.7-μm band minimum, which we attribute to the presence of relatively fresh (less space-weathered) material excavated from the sub-surface by crater-forming impacts. For three craters, we find an anti-correlation between spectral slopes and reflectance factor for a series of spectra acquired during a specific scan, where we observe that spectra become redder and darker towards the center of the crater. We attribute this to the presence of fine-particulate regolith. Localized spectral heterogeneities are apparent inside a prominent equatorial crater on Bennu, which is one of the asteroid's oldest geological features. We propose that such local spectral heterogeneities could be used as a tracer of mass movement on Bennu. We show that younger craters are redder, brighter, and have deeper 2.7-μm bands. Comparing global average spectral values of Bennu and crater frequency distributions as a function of the chosen spectral parameters, we find that craters evolve to assume the global average spectral properties of Bennu. A positive correlation identified between the reflectance factor and 2.7-μm band depth suggests that brighter craters tend to be more hydrated. Finally, we put into context, the results from the Small Carry-on Impactor experiment by the Hayabusa2 spacecraft, which created an artificial crater on the near-Earth asteroid (162173) Ryugu.

International audience; Organic matter directly observed at the surface of an inner planetary body is quite infrequent due to the usual low abundance of such matter and the limitation of the infrared technique. Fortuitously, the Dawn mission has revealed, thanks to the Visible and InfraRed mapping spectrometer (VIR), large areas rich in organic matter at the surface of Ceres, near Ernutet crater. The origin of the organic matter and its abundance in association with minerals, as indicated by the low altitude VIR data, remains unclear, but multiple lines of evidence support an endogenous origin. Here, we report an experimental investigation to determine the abundance of the aliphatic carbon signature observed on Ceres. We produced relevant analogues containing ammoniated-phyllosilicates, carbonates, aliphatic carbons (coals), and magnetite or amorphous carbon as darkening agents, and measured their reflectance by infrared spectroscopy. Measurements of these organic-rich analogues were directly compared to the VIR spectra taken from different locations around Ernutet crater. We found that the absolute reflectance of our analogues is at least two orders of magnitude higher than Ceres, but the depths of absorption bands match nicely the ones of the organic-rich Ceres spectra. The choices of the different components are discussed in comparison with VIR data. Relative abundances of the components are extrapolated from the spectra and mixture composition, considering that the differences in reflectance level is mainly due to optical effects. Absorption bands of Ceres’ organic-rich spectra are best reproduced by around 20 wt.% of carbon (a third being aliphatic carbons), in association with around 20 wt.% of carbonates, 15 wt.% of ammoniated-phyllosilicate, 20 wt.% of Mg-phyllosilicates, and 25 wt.% of darkening agent. Results also highlight the pertinence to use laboratory analogues in addition to models for planetary surface characterization. Such large quantities of organic materials near Ernutet crater, in addition to the amorphous carbon suspected on a global scale, requires a concentration mechanism whose nature is still unknown but that could potentially be relevant to other large volatile-rich bodies.

We present a multidisciplinary analysis of Lermontov crater, located at 15.24°N, −48.94°E in the Kuiper quadrangle of Mercury. By means of MESSENGER multiband MDIS-WAC and monochrome MDIS-NAC images, we prepare a high-resolution geological map of the crater and its closest surroundings, highlighting the presence of coexisting hollows and pyroclastic deposits on its floor. On the photometrically corrected MDIS-WAC multiband dataset, we apply an unsupervised clustering technique that spectrally separates the different materials located both inside and outside Lermontov crater. We observe that the pyroclastic deposits located on the crater’s floor have a steep, red spectral behaviour dominated by the presence of a mixture of various pyroxenes containing Ti and Ni. On the contrary, the vents’ rims are characterised by several hollows whose spectral slope is bluer than that of the pyroclastic deposits. By comparing the vent hollows to the hollows located farther out on the crater floor, we observe a steeper 0.62–0.82 ​μm spectral trend for those within the vents. The vent hollows’ spectrum is more similar to the pyroclastic one in the above mentioned wavelength range. In addition, the vent hollows 0.55 ​μm absorption band could be related to CaS, while the small differences in slope at 0.48 ​μm and 0.62 ​μm could be due to the presence of other volatiles compounds, such as MgS or chlorides. When compared to hollows located in other hermean geological settings, Lermontov hollows are characterised by steeper spectra. This supports the interpretation that when hollows form, their bright deposits do not completely overwrite the spectral signature of the surrounding terrain, and their spectroscopic appearance is mixed with the composition of the terrain where they form.

International audience

Through laboratory analyses it is possible to study the physical and chemical processes involving prebiotic molecules, the building blocks of life. Today thanks to the advent of new generation of (sub-) millimeter and centimeter interferometers (ALMA, NOEMA, ngVLA), an increasing number of interstellar complex organic molecules (iCOMs) is observed in star forming regions, pre-stellar dense cores, hot corinos, jets and outflow ardound protostars [1, 2, 3]. Hot corinos are inner compact (100 K) regions of some protostars [4]. In these high-temperature regions, thermal desorption is the physical process responsible for the sublimation of frozen mantles into the gas phase and so for the presence of a rich chemistry [5] in the gas phase. On the other hand, iCOMs are difficult to observe in protoplanetary disks, where, for a solar-type star, the region where the temperature reaches the values for the desorption and release into the gaseous phase of water and iCOMs (water snow line) is too close to the star (≤5 au). This region is difficult to solve but a new perspective is provided by objects such as the FU Ori systems in which the young central star undergoes a sudden increase in brightness which leads to heating of the disk and quick expansion of the snow lines to large radii. This phenomenon has been observed in the protoplanetary disk around the protostar V883 Ori [6]. Thanks to the increase in temperature of the disk and the consequent thermal desorption of the molecules, five iCOMs were recently detected: methanol, acetone, acetonitrile, acetaldehyde, and methyl formate [7]. Moreover, outbursting young stars are good new targets for looking for organic complex molecules that thermally desorb from icy mantles. The interpretation of observations can benefit from laboratory activities, where it is possible to simulate the thermal desorption process and UV irradiation of complex molecules under simulated space conditions. Furthermore, laboratory studies on thermal desorption are fundamental to constrain parameters such as the thermal desorption temperature of a given molecule and its fragments, and the binding energies involved. Here we reported the results that we have recently published about temperature-programmed desorption (TPD) analysis of pure formamide (HCONH2) ice and in the presence of TiO2 dust, before and after UV irradiation. We found that pure formamide desorbed at 220 K in high vacuum regime and after UV irradiation it fragmented mainly into NH2, HCO and CH2NO. These fragments are more volatile and desorbed before formamide (~180 K) at the same desorption temperature of water. The presence of water was due to residual deposition in the high vacuum chamber. It is reasonable to think, therefore, that the sublimation of water ice was responsible for releasing more volatile species. The same phenomenon probably occurs in the space where water is the most abundant molecule. Going forward with our investigation, we reproduced the condensation, irradiation, and desorption experiments with a substrate of TiO2 dust. In presence of grains, we observed evidence for a change in desorption temperature. Formamide desorption from TiO2 dust occurred at higher temperatures, that is, around 30 K above the temperature at which desorption takes place for pure formamide. A higher desorption temperature is direct evidence of the interactions described by the Van der Waals forces that were occurring between the molecule and the grains. The molecule interacts and diffuses into the grains and this is confirmed by the values of the binding energy that we found. When formamide desorbed directly from the cold finger of the cryostat (copper chromate surface), the binding energy found was (5.9 ± 0.3)·103 K; while when it desorbed from TiO2 dust, the binding energy found was (1.35 ± 0.08)·104 K, a value two times higher [8]. Therefore, in the chemical models of sublimation, it is essential to take into account physisorption of iCOMs on grain surfaces and their diffusion to correctly describe the desorption process, that is, to constrain desorption temperatures and binding energies [8]. Furthermore, our experiments show something more than the desorption temperature and the binding energy of formamide. The molecular fragments observed in laboratory (NH2, HCO and CH2NO) can be used to indirectly measure the presence of formamide through detection of relative abundance (e.g., [NH2]/[HCO]∼4).We reported also preliminary results on laboratory studies about thermal desorption of ice mixtures of acetaldehyde and acetonitrile from crystalline olivine grains.These studies offer support to observational data and improve our understanding of the role of the grain surface in enriching the chemistry in space. References[1]Beltrán, M. T. et al. 2009, The Astrophysical Journal Letters, 690 [2] Rivilla, V. M. et al. 2017, Astronomy & Astrophysics, 598 [3] Codella, C. et al. 2015, Mon. Not. R. Astron. Soc., 449 [4]Ceccarelli, C. et al. 1999, Astronomy and Astrophysics, 342[5] López-Sepulcre, A. et al. 2015, MNRAS, 449[6] Cieza, L. A. et al. 2016, Nature, 535, Issue 7611[7] Lee, J. et al. 2019, Nature Astronomy,3, 314[8] Corazzi, M. A. et al. 2020, A&A, 636, A63

Introduction OVIRS [1, 2] acquired visible to near-infrared spectra of asteroid Bennu’s surface showing an asymmetric absorption band centered at 2.74 ± 0.01 μm [3], attributed to the presence of hydrated phyllosilicates. This feature is widespread across Bennu’s surface. Such an absorption band has been detected in some carbonaceous chondrite meteorites [4, 5].In this study, we report the results from two distinct methods to estimate the hydration of Bennu’s surface. We calculated the normalized optical path length (NOPL) as well as the effective single particle absorption thickness (ESPAT) [6, 7, 8] on Bennu’s hydration band and on the selected meteorite spectra. For both methods, we compare meteorite results with their H2O/OH– H content, to estimate a H2O/OH– H content of Bennu’s average surface. Carbonaceous chondrite meteorite H2O/OH– H contents are derived from laboratory studies [9, 10]. Data Analysis Bennu spectra. Analysed spectra were acquired by OVIRS during Equatorial Station 3 (EQ3) of the Detailed Survey mission phase, on May 9, 2019, at 12:30 pm local solar time [11]. The reflectance spectra have been calibrated and photometrically corrected to an incidence angle of 0°, emission angle of 30°, and phase angle of 30°, using a McEwen photometrical model [12].Meteorite spectra. We used three sets of meteorite absolute reflectance spectra, from [4,5], [8], and [13]. For each set, powdered meteorite sample spectra were measured under vacuum (asteroid-like conditions).We selected over 40 meteorites for which bulk H values have been independently measured [9, 10]. In the case of Orgueil, Bells, and Tagish Lake, several samples were analysed and several H contents were ultimately derived [9, 14], all of which were used. Methods Normalized Optical Path Length (NOPL). The NOPL parameter was calculated as described in [6, 7, 8] on each meteorite spectrum, each individual Bennu reflectance spectrum, and the global average spectrum of Bennu. A linear continuum was fitted from 2.67 to 3.3 μm. The wavelength, at which the NOPL parameter is calculated, is the mean band minimum position for the EQ3 data set at 2.73 μm. Methods used to locate the band minimum are described in [3].Effective Single Particle Absorption Thickness (ESPAT). The ESPAT parameter was calculated following the method of [6, 7, 8]. Absolute reflectance spectra of meteorites and Bennu’s surface were first converted into single-scattering albedo spectra [6, 7, 8]. A linear continuum was then fitted from 2.67 to 3.3 μm and the ESPAT parameter is calculated at 2.73 μm as well. Our analyses do not include the organic absorption bands, present longwards of ~3.3 μm [11, 15]. Thus, we compare NOPL and ESPAT results with the hydrogen content of H2O/OH– groups in hydrated phyllosilicates only, measured for the selected meteorites [9, 10]. Results Figure 1 shows the NOPL parameter variations across Bennu’s surface using EQ3 spectra.Figure 1: Map of NOPL values computed at 2.73 μm for each EQ3 spectrum of Bennu.We find a linear correlation (Figure 2) between the NOPL parameter calculated at 2.73 μm on meteorite spectra and the meteorite H2O/OH– H content.Using this linear correlation, for the NOPL calculated on Bennu’s EQ3 average spectrum, we estimate a H2O/OH– H content for Bennu’s average surface of 0.54 ± 0.11 wt.%. Figure 2: Linear correlation between NOPL calculated at 2.73 μm and H2O/OH– H content of the seven selected meteorites (in colored points), and for average Bennu (blue circle).As with the NOPL parameter, we also find a linear correlation between the ESPAT parameter calculated at 2.73 μm on meteorite spectra and the meteorite H2O/OH– H content. We therefore estimate a H2O/OH– H content for Bennu’s average surface of 0.49 ± 0.13 wt.%, using Bennu’s EQ3 mean ESPAT value and the latter correlation. Discussion and ConclusionThe H2O/OH– H content for Bennu’s average surface obtained using NOPL parameters is consistent with the range obtained with the ESPAT parameter. Both methods are based on estimating global H content (in H2O/OH– groups of hydrated phyllosilicates) by analogy with meteorite data. The values of H2O/OH– H content of Bennu’s average surface we obtained are 0.54 ± 0.11 and 0.49 ± 0.13 wt.% using the NOPL parameter and the ESPAT parameter, respectively. From our results (Figure 2), Bennu’s average surface is most similar to heated CMs and Tagish Lake. Both estimated H2O/OH– H content ranges of Bennu’s average surface are more consistent with those of CM meteorites (0.46–1.36 wt%), Tagish Lake (0.50–0.69 wt.%), CR meteorites (0.30–1.20 wt.%), and CO meteorites (0.49–0.52 wt.%) [3, 9]. The gaussian modeling of the hydration band will complete those results. AcknowledgementsThis material is based on work supported by NASA under Contract NNM10AA11C issued through the New Frontiers Program. AP, MAB, FM, SF, PH and JDPD acknowledge funding support by CNES. INAF participation was supported by Italian Space Agency grant agreement n. 2017-37-H.0. We are grateful to the entire OSIRIS-REx Team for making the encounter with Bennu possible. References[1] Lauretta D. S. et al. (2017) Space Sci. Rev. 212, 925-984. [2] Reuter D. C. et al. (2018) Space Sci. Rev. 214, 54. [3] Hamilton V. E. et al. (2019) Nat. Astron. 3, 332. [4] Takir D. et al. (2013) Meteorit. Planet. Sci. 48, 1618–1637. [5] Takir D. et al. (2019) Icarus 333, 243–251. [6] Milliken R. E. et Mustard J. F. (2005) JGR, 110, E12001. [7] Milliken R. E. et al. (2007) JGR, 112, E08S07. [8] Garenne A. et al. (2016) Icarus, 264, 172-183. [9] Alexander C.M.O’D. et al. (2012) Science, 337, 721-723. [10] Alexander C.M.O’D. et al. (2013) Geochim. Cosmochim. Acta, 123, 244-260. [11] Simon et al. (in revision) Science. [12] Zou X.-D. et al., this meeting. [13] Potin S. et al. (2020) Icarus, 348, 113826. [14] Gilmour C. M. et al. (2019) Meteorit. Planet. Sci. 54, 1951–1972. [15] Kaplan et al. (2020) LPSC LI, 1050.

1. IntroductionOrigins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS-REx) is a NASA New Frontiers mission to return a sample of near-Earth asteroid (101955) Bennu. The OSIRIS-REx spacecraft is equipped with a suite of scientific instruments [1], including the OSIRIS-REx Camera Suite (OCAMS) and the OSIRIS-REx Visible and InfraRed Spectrometer (OVIRS), among others. OCAMS’s high-spatial-resolution images of Bennu’s surface facilitate the identification of regions of interest, characterization of surface morphology, and mapping of relative surface albedo [2]. OVIRS is a point spectrometer that measures surface composition [3]. The OVIRS footprint during the Reconnaissance phase of the mission [1] had an observational field of view with diameters between 5 to 9 m.We search for and distinguish organics and carbonates on the surface of Bennu by studying the shape of the 3.4-micron feature, as observed by the OVIRS spectrometer during reconnaissance of candidate sampling sites [4]. Aliphatic organics have vibrational stretching bands at 3.4 microns, and the CO32- anion in carbonate minerals has an overtone of a fundamental asymmetric vibrational stretch, also at 3.4 microns. Organics on asteroids are hypothesized to be related to the organic materials delivered to Earth during the early bombardment phase of Earth’s development [5]. Carbonates record evidence of aqueous processes on Bennu [6], and together the organics and carbonates provide evidence for Bennu’s alteration history.We present the results of a search for Bennu spectral matches to specific laboratory carbonate spectra and meteoritic aliphatic organic spectra, in the wavelength range from 3.2 to 3.6 microns. The carbonate spectra were obtained from the RELAB facility at Brown University [7], and the insoluble organic material (IOM) spectra were obtained from [8]. For the carbonates, we test ~10 representative spectra each of calcite, dolomite, and magnesite. For the organic IOM, we test spectra such as Tagish Lake, Cold Bokkeveld, Mighei, Murchison, and Orgueil.2 Data collection and preparation2.1 Spectrum preparation To prepare laboratory and OVIRS spectra for band-match testing, we first divide every spectrum by a continuum, defined as a second order polynomial. The parabola is constrained using reflectance values at the wavelengths 2.95, 3.24, 3.6 microns. We then “stretch” the band by normalizing each spectrum such that the band minimum occurs at 0.0 and the maximum occurs at 1.0. Thus, we are only comparing the band shapes, as all other quantitative information has been removed by the continuum normalization and the band stretching. 2.2 K-S parameter testWe apply a Kolmogorov-Smirnov (K-S) parameter test to find which laboratory spectra best fit the OVIRS spectra. We compare each laboratory spectrum to the entire OVIRS data set. The K-S parameter is an evaluation of the maximum discrepancy between two cumulative distribution functions (Figure 1). That is, we calculate the cumulative sum of the laboratory and OVIRS spectra and find the points of maximum discrepancy. The smaller the discrepancy, the better the fit. 3 Results Figure 1 shows an example match between an OVIRS spectrum from Bennu and a laboratory spectrum of calcite. Because the K-S parameter has a very low value (We will present maps of where carbonate and organic material is detected on Bennu and discuss our search for associations or correlations with boulders or other surface properties.AcknowledgementsThis material is based upon work supported by NASA under Contract NNM10AA11C issued through the New Frontiers Program. INAF participation was supported by Italian Space Agency grant agreement n. 2017-37-H.0. We are grateful to the entire OSIRIS-REx Team for making the encounter with Bennu possible.References[1] Lauretta, D.S. et al. (2017). OSIRIS-REx: Sample Return from Asteroid (101955) Bennu. Space Sci. Rev. 212, 925–984.[2] Rizk, B. et al. OCAMS: the OSIRIS-REx camera suite. Space Sci Rev (2018) 214:26 https://doi.org/10.1007/s11214-017-0460-7[3] Reuter, D.C. et al. (2018). The OSIRIS-REx Visible and InfraRed Spectrometer (OVIRS): Spectral Maps of the Asteroid Bennu. Space Sci. Rev. 214, 54.[4] V. E. Hamilton. VNIR-TIR spectroscopy of (101955) Bennu. This conference.[5] Anders, Edward. Pre-biotic organic matter from comets and asteroids. Nature 342.6247 (1989): 255-257.[6] Kaplan, H. H., et al. Evidence of Organics and Carbonates on (101955) Bennu. LPI 2326 (2020): 1050.[7] Pieters, C.M., et al. Reflectance Experiment Laboratory (RELAB) Description and User's Manual. NASA Technical Reports Server. (2004). Document ID, 20040129713[8] Kaplan, H.H., et al. Reflectance spectroscopy of insoluble organic matter (IOM) and carbonaceous meteorites. Meteorit Planet Sci, 54 (2019): 1051-1068. doi:10.1111/maps.13264

IntroductionAsteroid (65803) Didymos is an S-type [1] Apollo binary system characterized by a 780±30 m size primary, called Didymos, and a 164±18 m size secondary, called Dimorphos, orbiting at a distance of ~1.19 km [2]. The primary rotation period is 2.26 h [2], close to the 2.2 h disruption spin barrier [3], while the period of revolution of Dimorphos around the primary is 11.9217+0.0002 h [4]. This asteroid has been selected as the target of the Double Asteroid Redirection Test (DART, [5]), whose main goal is to impact Dimorphos at a speed of 6.6 km/s on September 30, 2022, thereby demonstrating the kinetic impactor technique and evaluating the resulting impulsive deflection.The scientific camera onboard DART is called DRACO, i.e. the Didymos Reconnaissance and Asteroid Camera for Op-nav [6]: its main goals are to image Didymos for optical navigation, to resolve the two bodies and support the spacecraft autonomous navigation to the target, and to locate the impact site precisely and characterize its local surface features. To complement such observations, the Light Italian Cubesat for Imaging of Asteroids (LICIACube, [7]) will be released from DART ten days before the impact, and autonomously guided through a flyby with closest approach distance of ~55 km from the target. LICIACube cameras LEIA (LICIACube Explorer Imaging for Asteroid - narrow angle camera) and LUKE (LICIACube Unit Key Explorer – wide angle camera) will then safely witness the redirection test in-situ, while its crater, as well as the ejecta and plume are being formed.Boulders SFD on Didymos systemBoulders/large blocks on asteroids are mainly interpreted as produced by target fragmentation and excavation due to high-velocity impact processes. They are the largest fragments excavated during an impact and are typically found within the crater or in its proximity, because they have not reached the escape velocity [8]. Instead, on rubble-pile asteroids boulders (typically the largest ones) are products of the reaccumulation process that formed the minor body itself, and may not be correlated to the observed craters [9]. For both cases, these blocks provide information on impact cratering processes occurring on low gravity bodies or on their parent body disruption event: their size-frequency distribution (SFD) fitting indices are therefore pivotal to provide hints on the fragment/boulder formation and/or degradation processes.Deriving boulder SFD and the corresponding power/exponential-law indices has been an important scientific topic addressed in several fly-by and orbital missions to minor bodies [e.g. 10-12]: it will be accomplished on the Didymos system as well.Four minutes before the impact the last image that contains all of Didymos will be taken by DRACO, with an expected spatial scale of 7 m/pixel. 120 seconds before impact, the last DRACO image containing any part of Dydimos will be taken, with a maximum resolution of 3.5 m [13]. DRACO will image all of Dimorphos ~50 cm/pixel ~17 seconds before impact and plans to return at least one higher-resolution image before impact. These final image(s) will have pixel scales At closest approach (CA), LICIACube/LEIA will image the surface of Dimorphos at 1.4 m/px [7]. If the DART crater will be observed through LEIA (it may be close to the limb during CA, hence the challenging imaging condition), we will be able to identify all boulders larger than 4.0-7.0 m located on the impacted side of Dimorphos, discerning those that have been generated/fragmented/moved after the DART impact from the ones previously imaged through DRACO. In addition, LEIA will image the non-impacted side of Dimorphos (not observed by DRACO) with resolutions ranging from 1.5 to 5 m: this will enable the characterization of the boulders SFD of the secondary down to 4.5 m.By comparing both the pre-, post- and non-impacted surface areas we will have the unique opportunity to witness how the boulders SFDs and densities/m2 will change as a result of a well characterized, hypervelocity impact. We will therefore test if the generation of a crater results in a different power-law distribution of boulders than the one observed on other S-type asteroids, such as (433) Eros and (25143) Itokawa [8,9], as well as recently observed carbonaceous asteroids, (101955) Bennu [12] and (162173) Ryugu [15].Acknowledgments: This research was supported by the Italian Space Agency (ASI) within the LICIACube project (ASI-INAF agreement AC n. 2019-31-HH.0).References: [1] de León, J. et al. (2010) Astron. Astrophys, 517, A23. [2] Naidu, S.P. et al. (2020) Icarus, 348, 113777. [3] Pravec P. and Harris A.W. (2000) Icarus, 148, 12-20. [4] Pravec, P. et al. (2006) Icarus, 181, 63. [5] Cheng A. F. et al. (2016) Planet. Space Sci., 121, 27-35. [6] Fletcher, Z.J. et al. (2016) 3rd Inst. Planetary Missions, 4043. [7] Dotto, E. et al., (submitted), Planet. Space Sci. [8] Thomas, P.C., et al. (2001) Nature 413, 394. [9] Michikami, T. et al. (2008), Earth Planets Space, 60, 13-20. [10] Lee, S.W., et al. (1986) Icarus 68, 77. [10] Geissler, P., et al. (1996) Icarus 120, 140. [11] Pajola, M. et al. (2015), Astron. Astrophys. 583, A37. [12] DellaGiustina, D. et al. (2019), Nat.Astron. 3, 341-351. [13] Cheng, A. F. et al. (2018) Planet. Space Sci., 157, 104-115. [14] Barnouin, O. et al. (2019). LPSC 50 abst. 2448. [15] Watanabe, S. et al. (2019), Science, 364, 6437, 268-272.

IntroductionAstroBio CubeSat (ABCS) is an Italian Space Agency (ASI) 3U CubeSat (100x100x340 mm) selected by European Space Agency (ESA) to be launched with the Vega C qualification maiden flight, as piggy back of the ASI LARES2 main satellite, by the end of 2020. ABCS will be deployed in an approximately circular orbit, with about 5900 km altitude and 70° of inclination. It implies that ABCS will spend a significant part of the orbital period within the internal Van Allen belt, close to its maximum. The radiation environment is characterized by a very high flux of charged particles, which have a significant effect on electronic components in terms of permanent damages due to accumulated dose effects and single events. Considering the extremely harsh space conditions, the estimated mission lifetime useful to perform the payload experiments should be defined in 3 months.ABCS Project is funded and managed by ASI in cooperation with INAF-Astrophysical Observatory of Arcetri, that will coordinate the scientific and engineering team. Partners of the projects are the School of Aerospace Engineering of Sapienza University of Rome, the University of Bologna, the University of Torino, and Kayser Italia.ABCS PayloadABCS will host a mini laboratory payload based on an innovative lab-on chip technology suitable for research in astrobiology. The objective is to test in space environments an automatic laboratory able to provide a highly integrated in-situ multiparameter platform that uses immunoassay tests exploiting chemiluminescence detection by means of on-chip a-Si:H photodiodes. The experiment will consist in a set of lateral flow immunoassays (LFIA) on nitrocellulose support where target biomolecules are immobilized in specific test areas. Reagents are deposited in a non-permanent fashion and in a dry form in the initial part (starting area) of the microfluidic path. When the reagents-delivery-system provides a volume of liquid reagent to the starting pad, capillary forces will guide the reagents through the LFIA microfluidic pathway. During the flow, liquid reagents will solubilize and transport along the path the deposited reagents, triggering specific reactions and allowing the chemiluminescence detection by the photodiodes.ABCS also mounts an ancillary radiation dose payload, to investigate the degradation of of electronic components exposed to the space environment. The device has twin components protected by established radiation screens, kindly provided by Thales Alenia Space Italia and by CESI, so that the degradation can be assessed on the basis of the difference between the observed currents.ABCS architecture and payload are based on the strong heritage gained by the research team with the ground validation of the PLEIADES (Planetary Life Explorer with Integrated Analytical Detection and Embedded Sensors) instrument, an R&D ASI project recently concluded.Enviromental challengesThe main challenges of the project are to mitigate the effects of the expected very high flux of charged particles, keeping the correct temperature (4°C/25°C) and pressure (about 1 atm) range for the payload to prevent reagents degradation. This invoked a series of technological solution to protect the payload. The pressurized environment is ensured by an inner aluminium box, hosting both the experiment and the main subsystems (batteries, on-board data handling, telemetry, tracking and control) hermetically sealed and providing shielding from radiation and charged particles. A thermal control system, including a passive control multi-layer insulation and an active heather mounted inside the pressurized box, maintain the temperature in the desired range.ConclusionABCS mission aims at evaluating the overall system functionality (delivery of reagents, mixing of chemicals, LoC characterization, detection of emitted photons, readout noise, etc.) such as the chemicals and biomolecules stability (reagents and antibodies employed in the experiment) in the extremely harsh environment.The in-orbit validation of the proposed technology would represent a significant breakthrough for autonomous execution of bio-analytical experiments in space with potential application in search for signs of life in planetary exploration missions, space biolabs without human support, health monitoring in manned missions.

Contact.The NASA New Frontiers asteroid sample return mission Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS-REx) has provided a large amount of data on the asteroid (101955) Bennu, including high-quality spectra obtained by the OSIRIS-REx Visible and InfraRed Spectrometer (OVIRS).Aims.To better constrain the surface properties and compositional variations of Bennu, we studied the visible and near-infrared spectral behavior across the asteroid surface by means of a statistical analysis aiming to distinguish spectrally distinct groups, if present.Methods.We applied theG-mode multivariate statistical analysis to the near-infrared OVIRS spectra to obtain an automatic statistical clustering at different confidence levels.Results.The statistical analysis highlights spectral variations on the surface of Bennu. Five distinct spectral groups are identified at a 2σconfidence level. At a higher confidence level of 3σ, no grouping is observed.Conclusions.The results at a 2σconfidence level distinguish a dominant spectral behavior group (group 1, background) and four small groups showing spectral slope variations, associated with areas with different surface properties. The background group contains most of the analyzed data, which implies a globally homogeneous surface at the spectral and spatial resolution of the data. The small groups with redder spectra are concentrated around the equatorial ridge and are associated with morphological surface features such as specific craters and boulders. No significant variation is detected in the band area or depth of the 2.74μm band, which is associated with hydrated phyllosilicate content. The spectral slope variations are interpreted as a consequence of different regolith particle sizes, and/or porosity, and/or space weathering, that is, the presence of more or less fresh material. The OSIRIS-REx mission primary sampling site, Nightingale, and a boulder known as the Roc, are redder than the background surface.

The search for molecular biosignatures at the surface of Mars is complicated by an intense irradiation in the mid- and near- ultraviolet (UV) spectral range for several reasons: (i) many astrobiologically relevant molecules are electronically excited by efficient absorption of UV radiation and rapidly undergo photochemical reactions; (ii) even though the penetration depth of UV radiation is limited, aeolian erosion continually exposes fresh material to radiation; and (iii) UV irradiation generates strong oxidants such as perchlorates that can penetrate deep into soils and cause subsurface oxidative degradation of organics.As a consequence, it is crucial to investigate the effects of UV radiation on organic molecules embedded in mineral matrices mimicking the martian soil, in order to validate hypotheses about the nature of the organic compounds detected so far at the surface of Mars by the Curiosity rover, as well as organics that will be possibly found by the next rover missions Mars 2020 and ExoMars 2020. In addition, studying the alteration of possible molecular biosignatures in the martian environment will help to redefine the molecular targets for life detection missions and devise suitable detection methods.Here we report the results of mid-UV irradiation experiments of Mars soil analog samples obtained adsorbing relevant organic molecules on a clay mineral that is quite common on Mars, i.e. montmorillonite, doped with 1 wt% of magnesium perchlorate. Specifically, we chose to investigate the photostability of a plausible precursor of the chlorohydrocarbons detected on Mars by the Curiosity rover, namely phthalic acid, along with the biomarkers of extant life L-phenylalanine and L-glutamic acid, which are proteomic amino acids, and adenosine 5’-monophosphate, which is a nucleic acid component.We monitored the degradation of these molecules adsorbed on montmorillonite through in situ spectroscopic analysis, investigating the reflectance properties of the samples in the Near InfraRed (NIR) spectral region. Such spectroscopic characterization of molecular alteration products provides support for two upcoming robotic missions to Mars that will employ NIR spectroscopy to look for molecular biosignatures, through the instruments SuperCam on board Mars 2020, ISEM, Ma_Miss and MicrOmega on board ExoMars 2020.

Mineral surfaces are energetic environments that can assist prebiotic organization by adsorbing selected molecules and allowing their concentration and chemical evolution, possibly toward complex (pre)biological systems. This dynamic rocky environment can also play a crucial role as promoters of chemical reactions towards increasing molecular complexity. Moreover, presence of minerals can mediate the effects of electromagnetic radiation and influence the photostability of biomolecules, catalyzing photoreaction or protecting molecules against degradation. Such interactions are responsible for the preservation/degradation mechanisms of organic molecules in space. In particular, the discovery of organic molecules on asteroids and comets confirms their role as transport and delivery vehicles of building blocks of life on Earth and possibly on other bodies of the Solar System, and the study of this kind of processes can improve our knowledge in astrobiology.Many different prebiotic and bio-molecules were detected in space and in meteorites, but among them amino acid glycine (H2NCH2COOH), is one of the most important. It is the simplest of the 20 biogenic amino acids and it is conceivably the link between complex organic molecules detected in our evolved Solar System and prebiotic molecules observed in the interstellar medium and protostellar environment. Laboratory simulations of UV processing may provide key insights into the survival of glycine and other biomarker in space environment, which is of particular relevance for upcoming space exploration missions on planetary surfaces, like ESA-Roscosmos ExoMars 2020, and sample return missions, like NASA OSIRIS-REx.We report a laboratory study of UV irradiation of glycine adsorbed on various space relevant minerals, i.e. forsterite, antigorite, spinel and pyrite, using a calibrated enhanced UV Xenon lamp, which demonstrated good performance as solar simulator. Comparing protective/catalytic effects of various minerals helps to unravel the role of rocky surfaces in the origin of life and provides hints for the search of organics in present and future robotic space exploration missions.

Introduction On September 30, 2022, NASA’s Double Asteroid Redirection Test (DART, [1]) mission will be the first space mission demonstrating the kinetic impactor method for planetary defense. DART will impact Didymos B (a 164±18 m secondary of asteroid (65803) Didymos [2]) with its mass of 650 kg and at a speed of 6.6 km/s. Such impact is expected to change the secondary orbital period by about 10 minutes. DART will carry as a piggyback the Light Italian Cubesat for Imaging of Asteroids (LICIACube, [3]) which will be released from DART ten days before the impact. LICIACube will provide evidence of the impact and will take multiple images of the target up to a distance of ~55 km from the target. The LICIACube narrow and wide angle cameras - LEIA (LICIACube Explorer Imaging for Asteroid) and LUKE (LICIACube Unit Key Explorer), respectively – will capture the post-impact processes coming from in situ events, such as the newly formed crater, the expanding ejecta and the dynamics of its plume. In particular, the measurement of the motion of the slow ( Dust plume model We use a 3D+t non-spherical dust model that solves the Euler dynamical and kinetic equations. Considering free-collisional dust regime we study the effects on the particle dynamics provided with different shapes, initial particle orientation and velocities as well as torque. Torque is computed from the law of variation of the angular momentum by using the Euler dynamic equations. The particles are assumed to be homogeneous, isothermal convex bodies, having the same physical properties of the target. The dust motion is governed by solar radiation pressure force, initial dynamical parameters (speed, orientation and torque) and gravity of the asteroid binary system. To compute the gravity we take into account that Didymos B is orbiting at distance of ~1.18 km the Didymos primary (780±80 m in size) [6]. As input we use the physical parameters obtained via numerically simulated impact into low-gravity and strength- dominated asteroid surface done with the iSALE numerical code [5]. A detailed description of the parameters set used in the impact modelling are reported in Table 1. As an example, in Fig.1, we show the iSALE simulation of the spatial distribution of tracer particles for 50 ms after the impact. Table 1: Paremeters used for iSAle simulation. A detailed description can be found in [5]. Fig. 1: A snapshot of the formation of the crater resulting from the iSALE modelling performed with parameters reported in Table 1. The colorbar represent the peak pressure of the ejecta tracer particles. Non-spherical dust motion in the plume We have studied the motion of non-spherical particles after the impact assuming various set of initial parameters coming from the iSALE simulations, such as particle mass, shape, initial orientation, launch position and computed velocity. The Didymos system physical parameters and particle temperature were taken from [7]. Here, in Fig. 2, we show the velocity and the distance from the surface where it has been reached for a prolate spheroid (aspect ratio = 2 [4]) with assumed density 2600 kg/m3. The particle mass is 7.45 x10-2 kg, the initial velocity 0.94 m/s, the launch position is 11 m from the center of the crater and the initial tilt of the initial velocity vector away from local surface normal is 46 degrees. We plotted the results for two cases: 1) only the Didymos B gravity field is considered and 2) the gravity of the whole binary is used. Our results show that the particle dynamics is sensitive to parameters such as orientation and ejection velocity. Fig. 2: Velocity and distance at which it has been achieved for a prolate particle (aspect ratio a/b = 2). The complete set of parameters is given in the text. The solid line indicates the case when only gravity of Didymos B was considered and the dashed line when the gravity of the whole binary was used (binary was approximated as a mass point). This study of dust dynamics in expanding ejecta together with LICIACube plume evolution images can further constrain the momentum transfer efficiency estimation as well as the ejecta velocity and dust size distribution in the “far-field” expanding plume. Acknowledgments This research was supported by the Italian Space Agency (ASI) within the LICIACube project (ASI-INAF agreement AC n. 2019-31-HH.0). References [1] Cheng A. F. et al. (2016) Planet. Space Sci., 121, 27-35. [2] de León, J. et al. (2010) Astron. Astrophys, 517, A23. [3] Dotto, E. et al., (submitted), Planet. Space Sci. [4] Ivanovski S. et al. (2017), Icarus 282, p. 333 - 350. [5] Raducan, S. D. et al. (2019), Icarus, 329, p. 282 - 295. [6] Michel, P. et al. (2016) Adv. Space Sci. 57, p. 2529 - 2547. [7] Yu Y. et al. (2017), Icarus 282, p.313 - 325

In Autumn 2022, the NASA Double Asteroid Redirection Test Mission (DART) will impact the surface of asteroid Dimorphos, a ~165 m body orbiting around asteroid (65803) Didymos, with the main aim to demonstrate the kinetic impactor technique for Planetary Defense. During the last minutes of the mission, the DRACO scienti c camera onboard DART will image the surface of both the primary and the secondary asteroids at different spatial scales, allowing the detection of boulders larger than 0.6-1.5 m on the impacted side of Dimorphos and larger than 11-21 m on Didymos. To complement such observations, the ASI "Light Italian Cubesat for Imaging of Asteroids" (LICIACube) will be released from DART ten days before the impact and will be then autonomously guided through a yby with closest approach distance of 55 km from Dimorphos. Through the LEIA (LICIACube Explorer Imaging for Asteroid) narrow angle camera, it will be possible to safely witness the DART redirection test in situ, while its crater and the ejecta and plume are being formed. At closest approach LEIA will image Dimorphos at ~2 m/px: we will therefore be able to identify all boulders larger than 4-7 m located on the imaged side of the asteroid. The analysis of the boulder surface densities and size frequency distributions (SFD) on Didymos and Dimorphos will be important to understand the processes that originated them (impact cratering versus parent body disruption). In addition, we will compare the SFD derived on the binary asteroid with those obtained on other S-type or carbonaceous minor bodies, highlighting the similarities and differences. In this work, the results of the boulder SFD expected from both LICIACube and DART images are presented. Acknowledgments: This research was supported by the Italian Space Agency (ASI) within the LICIACube project (ASI-INAF agreement AC n. 2019-31-HH.0).

Aims. Formamide (HCONH2) is the simplest molecule containing the peptide bond first detected in the gas phase in Orion-KL and SgrB2. In recent years, it has been observed in high temperature regions such as hot corinos, where thermal desorption is responsible for the sublimation of frozen mantles into the gas phase. The interpretation of observations can benefit from information gathered in the laboratory, where it is possible to simulate the thermal desorption process and to study formamide under simulated space conditions such as UV irradiation. Methods. Here, two laboratory analyses are reported: we studied formamide photo-stability under UV irradiation when it is adsorbed by space relevant minerals at 63 K and in the vacuum regime. We also investigated temperature programmed desorption of pure formamide ice in the presence of TiO2 dust before and after UV irradiation. Results. Through these analyses, the effects of UV degradation and the interaction between formamide and different minerals are compared.We find that silicates, both hydrates and anhydrates, offer molecules a higher level of protection from UV degradation than mineral oxides. The desorption temperature found for pure formamide is 220 K. The desorption temperature increases to 250 K when the formamide desorbs from the surface of TiO2 grains. Conclusions. Through the experiments outlined here, it is possible to follow the desorption of formamide and its fragments, simulate the desorption process in star forming regions and hot corinos, and constrain parameters such as the thermal desorption temperature of formamide and its fragments and the binding energies involved. Our results offer support to observational data and improve our understanding of the role of the grain surface in enriching the chemistry in space., Comment: In press Astronomy and Astrophysics, 13 pages, 12 figures

Asteroid (65803) Didymos is an S-type [1] Apollo binary system characterized by a 780±30 m size primary, called Didymos, and a 164±18 m size secondary, called Dimorphos, orbiting at a distance of ~1.19 km [2]. The primary rotation period is 2.26 h [2], close to the 2.2 h disruption spin barrier [3], while the period of revolution of Dimorphos around the primary is 11.9217+0.0002 h [4]. This asteroid has been selected as the target of the Double Asteroid Redirection Test (DART, [5]), whose main goal is to impact Dimorphos at a speed of 6.6 km/s on September 30, 2022, thereby demonstrating the kinetic impactor technique and evaluating the resulting impulsive deflection. The scientific camera onboard DART is called DRACO, i.e. the Didymos Reconnaissance and Asteroid Camera for Op-nav [6]: its main goals are to image Didymos for optical navigation, to resolve the two bodies and support the spacecraft autonomous navigation to the target, and to locate the impact site precisely and characterize its local surface features. To complement such observations, the Light Italian Cubesat for Imaging of Asteroids (LICIACube, [7]) will be released from DART ten days before the impact, and autonomously guided through a flyby with closest approach distance of ~55 km from the target. LICIACube cameras LEIA (LICIACube Explorer Imaging for Asteroid - narrow angle camera) and LUKE (LICIACube Unit Key Explorer - wide angle camera) will then safely witness the redirection test in-situ, while its crater, as well as the ejecta and plume are being formed.

Nata da una collaborazione fra l’Istituto europeo di astrobiologia e la scienziata ed editrice Julie Nováková, la raccolta di racconti “Strangest of All” accompagna i lettori in un viaggio alla scoperta della vita nell’universo, affiancando gli scenari immaginati da autori di fantascienza con le conoscenze scientifiche attuali