¹Daniele Fulvio,¹Ciprian Popa,¹Vito Mennella,²Federico Tosi,²SimoneDe Angelis,²Mauro Ciarniello,²Alessandro Mura,²Gianrico Filacchione
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.icarus.2023.115444]
¹INAF, Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, Naples 80131, Italy
²INAF, Istituto di Astrofisica e Planetologia Spaziali, Via del Fosso del Cavaliere 100, Rome 00133, Italy
Copyright Elsevier

Hydrated salts are thought to be a surface component of many different solid bodies in the solar system such as the icy-world satellites, especially the large ones of Jupiter and Saturn. In this context, three hydrated salts of interest in planetary sciences – natron (Na2CO3·10H2O), mirabilite (Na2SO4·10H2O), and epsomite (MgSO4·7H2O) – were selected and their NIR (0.8–3.6 μm) reflectance properties were studied as a function of temperature after diluting them in water. The main goal of these experiments is to characterize the evolution induced in the hydrated salt NIR spectra by the mixing and melting with water followed by freezing of the samples down to 95 K. Our results show that mixing of hydrated salts with water induces a complex phenomenology characterized by the formation of new bonds and absorption features. In addition, the shape and minimum position of the NIR spectral features here analyzed are temperature-dependent. The present laboratory study will be extremely useful to interpret the high-resolution data of Jupiter’s icy satellites surfaces which will be available in the next future thanks to the MISE and MAJIS instruments aboard NASA Europa Clipper and ESA JUICE spacecraft, respectively.