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arXiv · 1412.3894

Dust from Comet 209P/LINEAR during its 2014 Return: Parent Body of a New Meteor Shower, the May Camelopardalids

Masateru Ishiguro·Daisuke Kuroda·Hidekazu Hanayama·Jun Takahashi·Sunao Hasegawa·Yuki Sarugaku·Makoto Watanabe·Masataka Imai·Shuhei Goda·Hiroshi Akitaya·Yuhei Takagi·Kumiko Morihana·Satoshi Honda·Akira Arai·Kazuhiro Sekiguchi·Yumiko Oasa·Yoshihiko Saito·Tomoki Morokuma·Katsuhiro Murata·Daisaku Nogami·Takahiro Nagayama·Kenshi Yanagisawa·Michitoshi Yoshida·Kouji Ohta·Nobuyuki Kawai·Takeshi Miyaji·Hideo Fukushima·Jun-ichi Watanabe·Cyrielle Opitom·Emmanuel Jehin·Michael Gillon·Jeremie J. Vaubaillon
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Abstract

We report a new observation of the Jupiter-family comet 209P/LINEAR during its 2014 return. The comet is recognized as a dust source of a new meteor shower, the May Camelopardalids. 209P/LINEAR was apparently inactive at a heliocentric distance rh = 1.6 au and showed weak activity at rh < 1.4 au. We found an active region of <0.001% of the entire nuclear surface during the comet's dormant phase. An edge-on image suggests that particles up to 1 cm in size (with an uncertainty of factor 3-5) were ejected following a differential power-law size distribution with index q=-3.25+-0.10. We derived a mass loss rate of 2-10 kg/s during the active phase and a total mass of ~5x10^7 kg during the 2014 return. The ejection terminal velocity of millimeter- to centimeter-sized particles was 1-4 m/s, which is comparable to the escape velocity from the nucleus (1.4 m/s). These results imply that such large meteoric particles marginally escaped from the highly dormant comet nucleus via the gas drag force only within a few months of the perihelion passage.

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Masateru Ishiguro, Daisuke Kuroda, Hidekazu Hanayama, Jun Takahashi, Sunao Hasegawa, Yuki Sarugaku, Makoto Watanabe, Masataka Imai, Shuhei Goda, Hiroshi Akitaya, Yuhei Takagi, Kumiko Morihana, Satoshi Honda, Akira Arai, Kazuhiro Sekiguchi, Yumiko Oasa, Yoshihiko Saito, Tomoki Morokuma, Katsuhiro Murata, Daisaku Nogami, Takahiro Nagayama, Kenshi Yanagisawa, Michitoshi Yoshida, Kouji Ohta, Nobuyuki Kawai, Takeshi Miyaji, Hideo Fukushima, Jun-ichi Watanabe, Cyrielle Opitom, Emmanuel Jehin, Michael Gillon, Jeremie J. Vaubaillon. 2014-12-12. Dust from Comet 209P/LINEAR during its 2014 Return: Parent Body of a New Meteor Shower, the May Camelopardalids. https://doi.org/10.1088/2041-8205%2F798%2F2%2Fl34

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