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Imaging spectroscopy is a powerful remote sensing technique used to infer and map the chemical and physical properties of a planetary body. Such instruments have been already and successfully used for a thorough investigation of the surface and atmosphere (if present) of several Solar System objects. Examples are, among the others, the Visible and InfraRed Thermal Imaging Spectrometer (VIRTIS) for the ESA Rosetta and Venus Express missions, the Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité (OMEGA) on board the ESA/Mars Express, the Visible and Infrared Mapping Spectrometer (VIMS), the Visible and Infrared (VIR) mapping spectrometer and the JIRAM instrument onboard the NASA Cassini, Dawn and JUNO missions, respectively. Others have just been launched or will be operational in future, e.g. the Spectrometers and Imagers for MPS BepiColombo Integrated Observatory SYStem (SIMBIO-SYS) onboard the ESA BepiColombo mission and the MAJIS instrument on board the ESA JUICE mission.By taking advantage of this heritage and the potential availability of hardware spare, we explore the possibility to use an imaging spectrometer for the Hera asteroidal target, once adapted to the mission constraints and objectives. As an example, by adapting the VIHI spectrometer channel of SIMBIO-SYS, covering the visible and near-infrared spectral range (0.4-2.0 μm), it would be possible to infer and map the surface mineralogy, the physical properties of the surface regolith and derive potential regional and local trends with a spatial resolution not achievable from ground-based instrumentation. Furthermore, by coupling spectral and spatial capabilities, we could derive chemical and physical properties of the target. [ABSTRACT FROM AUTHOR]

The NASA Juno spacecraft is studying Jupiter's atmosphere in depth since August 2016. The Jupiter Infrared Auroral Mapper (JIRAM) experiment, one of the scientific instruments on board Juno, is composed of a two broad-band imager and an infrared spectrometer, dedicated to the auroral and chemical composition of the Jupiter's atmosphere. In particular, JIRAM spectrometer has made observations of the trihydrogen cation (H3+) emissions at auroal region latitudes (Adriani et al. 2017; Dinelli et al. 2017) and at mid-to-equatorial latitudes (Migliorini et al., submitted) across the Jupiter's planetary disc in the spectral band 2-5 μm. We focus on limb observations of the planet from 60° North to 60° South latitudes, to investigate the vertical distribution of the H3+ emissions as a function of latitude across Jupiter's dayside. H3+ volume mixing ratio (VMR) and atmospheric temperatures were retrieved from the H3+ emission features in the 3-4 μm spectral band, while H3+ concentration was derived by combining the previous quantities. Here we discuss results obtained from data acquired during the first and fifth Juno orbit around Jupiter, in August 2016 and February 2017 respectively. Differences between North and South hemispheres are also discussed. AcknowledgmentsThe project JIRAM is funded by the Italian Space Agency.ReferencesAdriani, A., A. Mura, M.L. Moriconi, B.M. Dinelli, F. Fabiano, et al. (2017), Preliminary Results from the JIRAM Auroral Observations taken during the first Juno orbit: 2 - Analysis of the Jupiter Southern H3+ emissions and Comparison with the North Aurora, Geophys. Res. Lett., 44, 4633-4640, doi: 10.1002/2017GL072905 Dinelli, B.M., et al. (2017), Preliminary Results from the JIRAM Auroral Observations taken during the first Juno orbit: 1 - Methodology and Analysis Applied to the Jovian Northern Polar Region, Geophys. Res. Lett., doi:10.1002/2017GL072929.Migliorini A., et al., H3+ characteristics in the Jupiter atmosphere as observed at limb with Juno/JIRAM, submitted to Icarus. [ABSTRACT FROM AUTHOR]