[P-PS04] Small Solar System Bodies: A New Insight from Hayabusa2, OSIRIS-REx and Other Space Missions

[PPS04-P14] Assessing the debris generated by the small carry-on impactor operated from the Hayabusa2 mission

*Motoo Ito¹, Yoshinori Takano², Yoko Kebukawa³, Takuji Ohigashi⁴, Moe Matsuoka⁵, Kento Kiryu³, Masayuki Uesugi⁶, Tomoki Nakamura⁷, Hayato Yuzawa⁴, Keita Yamada⁸, Hiroshi Naraoka⁹, Toru Yada⁵, Masanao Abe⁵, Masahiko Hayakawa⁵, Takanao Saiki⁵, Shogo Tachibana¹⁰ (1.Kochi Institute for Core Sample Research, JAMSTEC, 2.Biogeochemistry Research Center, JAMSTEC, 3.Yokohama National University, 4.UVSOR, IMS, 5.ISAS, JAXA, 6.JASRI/SPring-8, 7.Tohoku University, 8.Tokyo Institute of Technology, 9.Kyushu University, 10.University of Tokyo)

Keywords:C-type asteroid Ryugu, Hayabusa2 mission, Off-nominal assessment, Small carry-on Impactor, Carbonaceous materials

We have analyzed the carbonaceous materials generated by the explosion of an HMX (high-melting explosive) mixture in an Ar atmosphere in a laboratory simulation of the SCI (small carry-on Impactor) experiment. We used both non-destructive and destructive analytical techniques to identify the chemical nature of the materials. From SEM–EDS, we found the materials to be composed mainly of carbon, nitrogen, and oxygen, with a detectable amount of metals. Suitable parameters for identifying these materials are a FTIR peak at 1520 cm⁻¹, low reflectance and gentle red slope of FTIR spectrum compared with a Murchison CM2 chondrite, the Raman D and G bands, and the H, C, and N isotopic compositions and their spatial distributions. The scanning transmission X-ray microscopy (STXM)–XANES results provided the molecular nature of these highly aromatic materials, which was supported by results from TD–GC/MS. These results suggest that it is possible to distinguish either Ryugu samples or SCI materials as potential contaminants in a sample container by using proper combinations of analytical techniques. This assessment provides information useful for the analysis of the Ryugu asteroidal samples.