JpGU-AGU Joint Meeting 2017

Presentation information

[EE] Poster

P (Space and Planetary Sciences) » P-PS Planetary Sciences

[P-PS02] [EE] Small Bodies: Exploration of the Asteroid Belt and the Solar System at Large

Mon. May 22, 2017 3:30 PM - 5:00 PM Poster Hall (International Exhibition Hall HALL7)

convener:eleonora ammannito(University of California Los Angeles), Taishi Nakamoto(Tokyo Institute of Technology), Masanao Abe(Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency), Christopher T Russell(University of California Los Angeles), Sei-ichiro WATANABE(Division of Earth and Planetary Sciences, Graduate School of Science, Nagoya University)

[PPS02-P07] Polarimetric Study of (331471) 1984 QY1, a Potential Dormant Comet Candidate

*Jooyeon Kim1, Masateru Ishiguro2, Yoonsoo Park Bach2, Daisuke Kuroda3, Hiroyuki Naito4, Yuna Grace Kwon2, Yoonyoung Kim2, Masataka Imai7, Kiyoshi Kuramoto5, Makoto Watanabe6 (1.Department of Astronomy and Space science, Kyunghee University, 2.Department of Physics and Astronomy, Seoul National University, 3.National Astronomical Observatory of Japan, 4.Nayoro Observatory, 5.Division of Earth and Planetary Sciences, Hokkaido University, 6.Department of Applied Physics, Faculty of Science, Okayama University of Science, 7.Department of Cosmoscience, Graduate School of Science, Okayama University of Science)

Keywords:asteroid, polarimetry, potential dormant comet

Identification between asteroids and comets are fundamental to know the spatial distribution of small bodies in the solar system, and yet, it is challenging to find dormant comets in the list of known asteroids because their appearances are indistinguishable from asteroids. Here we provide a unique research to discriminate asteroids and dormant comets via ‘polarimetry’. We thus conducted a polarimetric observation of (331471) 1984 QY1 (hereafter QY1) using the Multi-Spectral Imager (MSI) on the 1.6-m Pirka Telescope from UT 2016 May 25 to June 24. The object has been regarded as a dormant comet candidate in terms of the dynamical property (i.e. the Tisserand parameter with respect to Jupiter TJ = 2.68, the probability of Jupiter-comet origin PJFC = 96 %; Bottke et al. 2002). We investigated the phase angle dependence of polarization degree of QY1, and found that it shows the polarization degree Pmax = 7.4 +/- 0.2 % around the phase angle α = 100 degree. The polarimetric property is similar to those of S-type asteroids rather than cometary nuclei. In this presentation, we introduce our observation and discuss about the possible origin of QY1 based on our observation together with the dynamical properties.