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

We conducted optical polarimetry and near-infrared spectroscopy of JAXA's Hayabusa2# mission target, (98943) 2001 CC₂₁, in early 2023. Our new observations indicate that this asteroid has a polarimetric inversion angle of ~20\(^\circ\), absorption bands around 0.9 and 1.9 \(\mu\)m, and a geometric albedo of 0.23\(\pm\)0.04. All these features are consistent with those of S-types but inconsistent with L-types. Based on this evidence, we conclude that JAXA's Hayabusa2# spacecraft will explore an S-type asteroid (more specifically, an L or LL chondrite-like object) with albedo and size (0.44-0.53 km when we assume the absolute magnitude of 18.8) similar to (25143) Itokawa.

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Description
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This ‘data’ directory contains the polarimetric and spectroscopic data of 2001 CC21 
used to derive the results in Geem et al. MNRAS Letter 2023 
(https://doi.org/10.48550/arXiv.2304.02917). 
See the published papers by Geem et al. (MNRAS Letter 2023)

If you need any questions, please contact Jooyeon Geem via her mail (ksky0422@snu.ac.kr). 

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Directory tree structure
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/data
 ├──/polarimetry
 │         └──/Instrument (FAPOL, HONIR and, MSI)
 │                   └──/Observation Date
 │                              └──/Filter (V or R)
 │                                         ├── *.fits      (Preprocessed image in FITS format)
 │                                          ├── mask_*.fits (Masking image in FITS format)
 │                                          └── *.mag.1     (IRAF Phot file containing target's center info.) 
 │
 └──/spectroscopy
            └──/Observation Date (230206 and 230205)
                       ├── obslog.txt (Observation log file)
                       └── *.fits (The extracted spectra using Spextool)