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arXiv · 2304.02917

Spectral Type and Geometric Albedo of (98943) 2001 CC21, the Hayabusa2# Mission Target

Jooyeon Geem·Masateru Ishiguro·Mikael Granvik·Hiroyuki Naito·Hiroshi Akitaya·Tomohiko Sekiguchi·Sunao Hasegawa·Daisuke Kuroda·Tatsuharu Oono·Yoonsoo P. Bach·Sunho Jin·Ryo Imazawa·Koji S. Kawabata·Seiko Takagi·Makoto Yoshikawa·Anlaug A. Djupvik·Julie Thiim Gadeberg·Tapio Pursimo·Oliver Durfeldt Pedros·Jeppe Sinkbaek Thomsen·Zuri Gray
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Abstract

We conducted optical polarimetry and near-infrared spectroscopy of JAXA's Hayabusa2# mission target, (98943) 2001 CC21, in early 2023. Our new observations indicated that this asteroid has a polarimetric inversion angle of ~21 deg, absorption bands around 0.9 and 1.9 um, and a geometric albedo of 0.285 +- 0.083. All these features are consistent with those of S-type but inconsistent with L-type. Based on this evidence, we conclude that JAXA's Hayabusa2# spacecraft will explore an S-type asteroid with albedo and size (0.42-0.56 km when we assume the absolute magnitude of 18.6) similar to (25143) Itokawa.

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Jooyeon Geem, Masateru Ishiguro, Mikael Granvik, Hiroyuki Naito, Hiroshi Akitaya, Tomohiko Sekiguchi, Sunao Hasegawa, Daisuke Kuroda, Tatsuharu Oono, Yoonsoo P. Bach, Sunho Jin, Ryo Imazawa, Koji S. Kawabata, Seiko Takagi, Makoto Yoshikawa, Anlaug A. Djupvik, Julie Thiim Gadeberg, Tapio Pursimo, Oliver Durfeldt Pedros, Jeppe Sinkbaek Thomsen, Zuri Gray. 2023-04-06. Spectral Type and Geometric Albedo of (98943) 2001 CC21, the Hayabusa2# Mission Target. https://doi.org/10.1093/mnrasl%2Fslad073

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