[U-06_28PO1] 太陽系小天体研究の新展開

[U06-P20] 探査候補となる地球近傍小惑星の可視分光観測

*黒田 大介¹、石黒 正晃²、高遠 徳尚³、長谷川 直⁴、安部 正真⁴、津田 雄一⁴、杉田 精司⁵、臼井 文彦⁶、服部 尭³、岩田 生³、今西 昌俊³、寺田 宏³、Choi Young-Jun⁷、渡邊 誠一郎⁸、吉川 真⁴ (1.国立天文台 岡山天体物理観測所、2.ソウル大学物理天文学科、3.国立天文台ハワイ観測所、4.宇宙航空研究開発機構宇宙科学研究所、5.東京大学新領域創成科学研究科、6.東京大学大学院理学系研究科、7.韓国天文宇宙科学研究院、8.名古屋大学大学院環境学研究科)

キーワード：小惑星, 可視分光観測, スペクトル分類

We present a unique data set of the taxonomic type of near-Earth asteroids (NEAs) accessible with available spacecraft.
The research on NEAs has entered a new phase thanks to sample-return space explorations together with state-of-the-art large ground-based telescopes. We made observations of twelve asteroids with Subaru, GEMINI-North, GEMINI-South and Okayama 188cm telescopes. They have low delta-v orbits with potential to be investigated by manned/unmanned spacecraft. Also, ten sub-km-sized bodies are included in them, and are one of remarkable characteristics in terms of an evolutionary scenario.
We find that eleven asteroids are classified as S-complex and one asteroid as V-type. Most S-complex asteroids (eight out of eleven, 〜70%) have spectra similar to subgroups of Q or Sq-type, suggesting that these objects are less matured against space weathering.
In this presentation, we show their spectra and discuss dominance of S-complex asteroids based on the previous research.