[P-PS04] 太陽系小天体：はやぶさ２等の宇宙ミッションからの新展開

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

*伊藤 元雄¹、高野 淑識²、癸生川 陽子³、大東 琢治⁴、松岡 萌⁵、桐生 健斗³、上椙 真之⁶、中村 智樹⁷、湯澤 勇人⁴、山田 桂太⁸、奈良岡 浩⁹、矢田 達⁵、安部 正真⁵、早川 雅彦⁵、佐伯 孝尚⁵、橘 省吾¹⁰ (1.海洋研究開発機構　高知コア研究所、2.海洋研究開発機構　生物地球化学センター、3.横浜国立大学、4.分子科学研究所 UVSOR、5.宇宙航空研究開発機構 宇宙科学研究所、6.JASRI/SPring-8、7.東北大学、8.東京工業大学、9.九州大学、10.東京大学)

キーワード：小惑星リュウグウ、はやぶさ２ミッション、Off-nominal assessment、Small carry-on Impactor、炭素質物質

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.