R5: Extraterrestrial materials

[R5-11] Shock metamorphism of the surface particles of asteroid Ryugu

*Naotaka Tomioka¹, Akira Yamaguchi², Motoo Ito¹, Masayuki Uesugi³, Naoya Imae², Naoki Shirai^4,5, Takuji Ohigashi^6,7, Makoto Kimura², Ming-Chang Liu⁸, Richard Greenwood ⁹, Kentaro Uesugi³, Aiko Nakato¹⁰, Kasumi Yogata¹⁰, Hayato Yuzawa⁶, Yu Kodama (1. JAMSTEC, 2. NIPR, 3. SPring-8, 4. Tokyo Metro. Univ., 5. Kanagawa Univ., 6. UVSOR, IMS, 7. KEK, 8. UCLA, 9. Open Univ., 10. JAXA)

Keywords:Hayabusa2, Asteroid Ryugu, Shock metamorphism, SEM/TEM

In order to clarify the mineralogical characteristics and shock effects of hydrated asteroids' materials, surface particles of the asteroid Ryugu collected by the Hayabusa2 spacecraft were investigated using SEM and TEM. Although the overall textures of the Ryugu particles examined in this study do not show significant shock effects, some shock-induced microfaults-like structures and a high-pressure phase of sulfide were identified. In this presentation, we will evaluate the shock pressure experienced by Ryugu particles based on these observations.