Laboratory investigations of the electromagnetic properties of a powdered L-chondrite

Abstract

IntroductionRadio Echo Sounding (RES) has been employed in planetary missions to survey the Moon, Mars, and Comet 67P/Churyumov-Gerasimenko (Porcello et al., 1974; Plaut et al., 2007; Kofman et al., 2015) and it will be applied, among others, in future investigations of the Galilean moons (JUICE mission - Grasset et al., 2013; EUROPA CLIPPER mission – Blankenship et al., 2018), and asteroids (e.g. AIDA mission - Herique et al., 2019). The ability of a radar signal to penetrate and image the subsurface layers depends on both the dielectric permittivity and magnetic permeability of the materials composing the crust. Thus, laboratory experiments are essential to improve our capability to estimate the radar performance and interpret the radar data collected in different scenarios. We present here the results of the electromagnetic measurements conducted for different porosities of a powdered L5 chondrite sample (a good simulant of the surface of Ganymede and S type asteroids), in the frequency range of interest for planetary radar sounders (1 MHz-1 GHz).MethodologyThe analyzed meteorite was classified as an ordinary L5 chondrite, with shock grade S2 and weathering W2 (Cosciotti et al.,2021). A fragment of the solid meteorite was pulverized in a jaw crusher and then sieved, to obtain five different granulometric samples, from