[U-06_28PO1] New Progress toward the Understanding of Small Solar System Bodies

[U06-P20] Visible wavelength spectroscopy of sub-km-sized Near-Earth Asteroids with low delta-v

*Daisuke KURODA¹, Masateru ISHIGURO², Naruhisa TAKATO³, Sunao HASEGAWA⁴, Masanao ABE⁴, Yuichi TSUDA⁴, Seiji SUGITA⁵, Fumihiko USUI⁶, Takashi HATTORI³, Ikuru IWATA³, Masatoshi IMANISHI³, Hiroshi TERADA³, Young-jun CHOI⁷, Sei-ichiro WATANABE⁸, Makoto YOSHIKAWA⁴ (1.Okayama Astrophysical Observatory, National Astronomical Observatory of Japan, 2.Department of Physics and Astronomy, Seoul National University, 3.Subaru Telescope, National Astronomical Observatory of Japan, 4.Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 5.Graduate School of Frontier Science, The University of Tokyo, 6.Graduate School of Science, The University of Tokyo, 7.Korea Astronomy and Space Science Institute, 8.Graduate School of Science, Nagoya University)

Keywords:

asteroid,visible spectroscopy,taxonomic classification

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.