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arXiv · 1812.01851

Investigation of surface homogeneity of (3200) Phaethon

Abstract

Time-series multi-band photometry and spectrometry were performed in Nov.-Dec. 2017 to investigate the homogeneity of the surface of asteroid (3200) Phaethon. We found that Phaethon is a B-type asteroid, in agreement with previous studies, and that it shows no evidence for rotational color variation. The sub-solar latitude during our observation period was approximately 55 degree S, which corresponded to the southern hemisphere of Phaethon. Thus, we found that the southern hemisphere of Phaethon has a homogeneous surface. We compared our spectra with existing spectral data to examine the latitudinal surface properties of Phaethon. The result showed that it doesn't have a latitudinal color variation. To explain this observation, we investigated the solar-radiation heating effect on Phaethon, and the result suggested that Phaethon underwent a uniform thermal metamorphism regardless of latitude, which was consistent with our observations. Based on this result, we discuss the homogeneity of the surface of Phaethon.

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Hee-Jae Lee, Myung-Jin Kim, Dong-Heun Kim, Hong-Kyu Moon, Young-Jun Choi, Chun-Hwey Kim, Byeong-Cheol Lee, Fumi Yoshida, Dong-Goo Roh, Haingja Seo. 2018-12-05. Investigation of surface homogeneity of (3200) Phaethon. https://doi.org/10.1016/j.pss.2018.12.001

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