Paper

Photometric Observations of 107P/Wilson-Harrington

Urakawa, Seitaro, Kitazato, Kohei, Takahashi, Noritsugu, Okumura, Shin-ichiro, Abe, Shinsuke, Shimizu, Yasuhiro, Ohta, Kouji, Sakamoto, Tsuyoshi, Kuroda, Daisuke, Yanagisawa, Kenshi, Hasegawa, Sunao, Nishiyama, Kota, Nagayama, Shogo, Ishiguro, Masateru, Kawai, Nobuyuki, Yoshida, Michitoshi, Yoshikawa, Makoto

2011

Overview

We present lightcurve observations and multiband photometry for 107P/Wilson-Harrington using five small- and medium-sized telescopes. The lightcurve has shown a periodicity of 0.2979 day (7.15 hour) and 0.0993 day (2.38 hour), which has a commensurability of 3:1. The physical properties of the lightcurve indicate two models: (1) 107P/Wilson-Harrington is a tumbling object with a sidereal rotation period of 0.2979 day and a precession period of 0.0993 day. The shape has a long axis mode (LAM) of L1:L2:L3 = 1.0:1.0:1.6. The direction of the total rotational angular momentum is around = 310, = -10, or = 132, = -17. The nutation angle is approximately constant at 65. (2) 107P/Wilson-Harrington is not a tumbler. The sidereal rotation period is 0.2979 day. The shape is nearly spherical but slightly hexagonal with a short axis mode (SAM) of L1:L2:L3 = 1.5:1.5:1.0. The pole orientation is around = 330, = -27. In addition, the model includes the possibility of binary hosting. For both models, the sense of rotation is retrograde. Furthermore, multiband photometry indicates that the taxonomy class of 107P/Wilson-Harrington is C-type. No clear rotational color variations are confirmed on the surface.

• Publisher: Cornell University Library, arXiv.org
• Subject: Angular momentum / Nutation / Periodic variations / Photometry / Physical properties / Rotation / Taxonomy / Telescopes / Tumblers / Tumbling