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

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.

5 pages, 3 figures, Submitted to MNRAS Letter on 2023 April 3

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Cited by in corpus (5)

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• Quantitative grain size estimation on airless bodies from the negative polarization branch. I. Insights from experiments and lunar observations
• Characterization of of (98943) 2001 CC${}_{21}$, the target of Hayabusa2$\#$
• Thermal and Optical Characterization of Near-Earth Objects: Science Commissioning of the Recently Upgraded Mid-Infrared Camera MIRSI on the NASA Infrared Telescope Facility