Very weak carbonaceous asteroid simulants I: mechanical properties and response to hypervelocity impacts
arXiv:2111.15279 · doi:10.1016/j.icarus.2020.113648
Abstract
The two on-going sample return space missions, Hayabusa2 and OSIRIS-REx are going to return to Earth asteroid regolith from the carbonaceous near-Earth asteroids Ryugu and Bennu. The two main processes that lead to regolith production are the micrometeorite bombardment and the thermal cracking. Here we report the production of a weak simulant material, analogue to carbonaceous meteorites with a CM-like composition, following the preliminary compositional results for Bennu and Ryugu. This asteroid simulant has compressive and flexural strength 1.8+/-0.17 and 0.7+/-0.07 MPa, respectively. The thermal conductivity (in air) of the simulant at room temperature is between 0.43 and 0.47 W/m/K. In order to distinguish the type of regolith that is produced by each of these processes, we present and discuss the results of the experimental campaign focused on laboratory hypervelocity impacts, using the 2-stage light-gas gun of the University of Kent, that mimic the micrometeorite bombardment. We find that this process produces both monomineralic and multimineralic fragments, resulting in a difficulty to distinguish the two processes, at least on these weak materials.
References in corpus (10)
- Cometary Origin of the Zodiacal Cloud and Carbonaceous Micrometeorites
- Introducing the Eulalia and new Polana asteroid families: re-assessing primitive asteroid families in the inner Main Belt
- Thermally induced stresses in boulders on airless body surfaces, and implications for rock breakdown
- Asteroid thermophysical modeling
- Thermophysical modeling of main-belt asteroids from WISE thermal data
- Rotational Characterization of Hayabusa II Target Asteroid (162173) 1999 JU3
- The Origins of Asteroidal Rock Disaggregation: Interplay of Thermal Fatigue and Microstructure
- Measuring the Fidelity of Asteroid Regolith and Cobble Simulants
- Ground-based Characterization of Hayabusa2 Mission Target Asteroid 162173 Ryugu: Constraining Mineralogical Composition in Preparation for Spacecraft Operations
- Impact cratering on porous targets in the strength regime