GRASSI, DavideDavideGRASSIMURA, AlessandroAlessandroMURAADRIANI, AlbertoAlbertoADRIANISindoni, GGSindoniAtreya, S KS KAtreyaFletcher, L NL NFletcherOrton, G SG SOrtonPLAINAKI, CHRISTINACHRISTINAPLAINAKITOSI, FedericoFedericoTOSIBIAGIOTTI, FrancescoFrancescoBIAGIOTTIOlivieri, AAOlivieriCASTAGNOLI, ChiaraChiaraCASTAGNOLID'AVERSA, EMILIANOEMILIANOD'AVERSAMIGLIORINI, AlessandraAlessandraMIGLIORINIMOIRANO, ALESSANDROALESSANDROMOIRANONOSCHESE, RaffaellaRaffaellaNOSCHESEPICCIONI, GIUSEPPEGIUSEPPEPICCIONISORDINI, RobertoRobertoSORDINIBolton, SSBolton2025-04-112025-04-1120240035-8711http://hdl.handle.net/20.500.12386/37053The Jupiter InfraRed Auroral Mapper (JIRAM) instrument onboard the Juno spacecraft performed repeated observations of Jupiter's North Equatorial Belt (NEB) around the time of 12th Juno pericenter passage on 2018 April 1. The data consist of thermal infrared images and show, among other atmospheric features, two bright Hotspots on the boundary between the NEB and the Equatorial Zone. Night-time images of the same areas at different emission angles were used to constrain the trend of the limb-darkening function. Comparison with simulated observations, computed for different emission angles, total opacities, single scattering albedo ω<SUB>0</SUB>, and asymmetry parameter g suggests that ω<SUB>0</SUB> ~ 0.90 ± 0.05 and g ~ 0.37 ± 0.15 provide best match with data. Subsequently, we computed the ω<SUB>0</SUB> and g resulting from different size distributions, taking into account the complex refractive indices of ammonium hydrosulfide (NH<SUB>4</SUB>SH) by Howett et al. [2007] and Ferraro et al. [1980]. Only the former data set is marginally consistent with JIRAM observations. Similarly, ammonia and hydrazine barely reproduce the experimental data. Tholin, although not usually considered a realistic component for Jupiter's aerosols, provides a better match for particle radii between 0.7 and 1 μm, both as a pure material as well as a thick coating over NH<SUB>4</SUB>SH cores. Notably, this radius range is consistent with the mean radius of aerosols as estimated by Ragent et al. [1998] on the basis of Galileo entry probe data. Comparison with literature suggests that similar results can be achieved by a large variety of contaminants bearing C-N bounds....STAMPAenArticle10.1093/mnras/stae18582-s2.0-85202439596https://academic.oup.com/mnras/article/533/2/2185/7725818?login=trueFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation::PE9_2 Planetary systems sciences