FOSSIL: I. The Spin Rate Limit of Jupiter Trojans

Chan-Kao Chang; Ying-Tung Chen; Wesley C. Fraser; Fumi Yoshida; Matthew J. Lehner; Shiang-Yu Wang; JJ Kavelaars; Rosemary E. Pike; Mike Alexandersen; Takashi Ito; Young-Jun Choi; A. Paula Granados Contreras; Youngmin JeongAhn; Jianghui Ji; Myung-Jin Kim; Samantha M. Lawler; Jian Li; Zhong-Yi Lin; Patryk Sofia Lykawka; Hong-Kyu Moon; Surhud More; Marco Munoz-Gutierrez; Keiji Ohtsuki; Tsuyoshi Terai; Seitaro Urakawa; Hui Zhang; Hai-Bin Zhao; Ji-Lin Zhou. The FOSSIL Collaboration

arXiv · 2107.06685

FOSSIL: I. The Spin Rate Limit of Jupiter Trojans

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Abstract

Rotation periods of 53 small (diameters $2 < D < 40$ km) Jupiter Trojans (JTs) were derived using the high-cadence light curves obtained by the FOSSIL phase I survey, a Subaru/Hyper Suprime-Cam intensive program. These are the first reported periods measured for JTs with $D < 10$ km. We found a lower limit of the rotation period near 4 hr, instead of the previously published result of 5 hr (Ryan et al. 2017; Szabo et al. 2017, 2020) found for larger JTs. Assuming a rubble-pile structure for JTs, a bulk density of 0.9 gcm$^{-3}$ is required to withstand this spin rate limit, consistent with the value $0.8-1.0$ gcm$^{-3}$ (Marchis et al. 2006; Mueller et al. 2010; Buie et al. 2015; Berthier et al. 2020) derived from the binary JT system, (617) Patroclus-Menoetius system.

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Chan-Kao Chang, Ying-Tung Chen, Wesley C. Fraser, Fumi Yoshida, Matthew J. Lehner, Shiang-Yu Wang, JJ Kavelaars, Rosemary E. Pike, Mike Alexandersen, Takashi Ito, Young-Jun Choi, A. Paula Granados Contreras, Youngmin JeongAhn, Jianghui Ji, Myung-Jin Kim, Samantha M. Lawler, Jian Li, Zhong-Yi Lin, Patryk Sofia Lykawka, Hong-Kyu Moon, Surhud More, Marco Munoz-Gutierrez, Keiji Ohtsuki, Tsuyoshi Terai, Seitaro Urakawa, Hui Zhang, Hai-Bin Zhao, Ji-Lin Zhou. The FOSSIL Collaboration. 2021-07-14. FOSSIL: I. The Spin Rate Limit of Jupiter Trojans. https://arxiv.org/abs/2107.06685

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