講演情報
[PPS03-12]The Next-Generation Small-Body Sample Return: Comet Exploration Mission to Unveil the Origin of the Solar System
*大澤 亮1、黒川 宏之2、嶌生 有理3、坂谷 尚哉3、深井 稜汰3、巽 瑛理4、青木 順5、癸生川 陽子6、次世代小天体サンプルリターン ワーキンググループ (1.国立天文台 JASMINE プロジェクト、2.東京工業大学 地球生命研究所、3.JAXA 宇宙科学研究所、4.カナリア天文物理学研究所、5.大阪大学大学院 生命機能研究科、6.横浜国立大学 大学院工学研究院 )
キーワード：
彗星、289P/Blanpain、サンプルリターン、太陽系形成
Understanding the environment where the solar system formed will elucidate the origin of the solar system. Interstellar matters reflect the history of nucleosynthesis and processing in the Galaxy. Organic materials in the interstellar medium could be preserved through star and planet formation processes and incorporated into the primordial Earth. Knowing the sources of the materials that formed the solar system and their fractions remains to be addressed. Another open issue is the growing process of bodies in the primordial solar system. The building components of planetesimals remain to be understood. A comprehensive theory of solar system formation should take into account observations of protoplanetary disks and the history of elemental synthesis in the Galaxy.
In this presentation, we introduce our proposal for a planetary exploration mission for sample return of interior materials and inspection of the internal structure of a comet nucleus. Present samples of presolar grains are limited and possibly processed and biased by size sorting. We excavate unaltered primordial ingredients of the solar system under the reaccumulated layer of a comet nucleus both for sample return and in-situ analysis. The void structure of comet nuclei will determine whether comets or icy planetesimals were hierarchically formed. We plan to use a bistatic radar system or seismometer to inspect the inner structure of the comet nucleus. The current mission design and expected payloads will be presented with 289P/Blanpain as a provisional target.
The proposed mission may address open problems in comet observation. Material compositions may vary with depth, possibly related to the origins of some observational diversities and correlations, for example, the D/H ratio correlation with the comet activity. An excavation experiment may create a new active region, providing an opportunity for coordinated observations with ground-based or space-borne telescopes. Discussions about the mission are ongoing. Contributions, such as proposals for backup objects and new instruments, would be greatly appreciated.
In this presentation, we introduce our proposal for a planetary exploration mission for sample return of interior materials and inspection of the internal structure of a comet nucleus. Present samples of presolar grains are limited and possibly processed and biased by size sorting. We excavate unaltered primordial ingredients of the solar system under the reaccumulated layer of a comet nucleus both for sample return and in-situ analysis. The void structure of comet nuclei will determine whether comets or icy planetesimals were hierarchically formed. We plan to use a bistatic radar system or seismometer to inspect the inner structure of the comet nucleus. The current mission design and expected payloads will be presented with 289P/Blanpain as a provisional target.
The proposed mission may address open problems in comet observation. Material compositions may vary with depth, possibly related to the origins of some observational diversities and correlations, for example, the D/H ratio correlation with the comet activity. An excavation experiment may create a new active region, providing an opportunity for coordinated observations with ground-based or space-borne telescopes. Discussions about the mission are ongoing. Contributions, such as proposals for backup objects and new instruments, would be greatly appreciated.