OSIRIS-REx & Hayabusa2 asteroid sample return missions: Impact process on “new” space materials.
Hayabusa2 and OSIRIS-REx small return space missions have returned invaluable information about the nature of the surfaces of the near-Earth asteroids Ryugu and Bennu, respectively. As surprise to predictions the surface of those asteroids is covered by boulders and, so -far in observations- not of fine regolith, as it was expected. Measurement of thermal conductivity on boulders of Ryugu in particular has shown a very low value, indicative of a very porous material. In our meteorite collection we have a few samples that could potentially match the mineralogy and mechanical properties of these asteroids, as weak materials are filtered out by Earth’s atmosphere.Here we report the production of a weak material, analogue to carbonaceous meteorites with a CM-like composition, following the preliminary compositional results for Bennu and Ryugu. A series of tests were conducted in order to investigate the thermo-mechanical properties of this simulant, which are very close to that of the weakest carbonaceous meteorites. Next we performed a series of hypervelocity impact experiments at the impact facility of the University of Kent in order to study their behaviour, aiming to understand the cratering features on the asteroid surfaces.
