Asteroid Ryugu Before the Hayabusa2 Encounter

Koji Wada; Matthias Grott; Patrick Michel; Kevin J. Walsh; Antonella M. Barucci; Jens Biele; Jürgen Blum; Carolyn M. Ernst; Jan T. Grundmann; Bastian Gundlach; Axel Hagermann; Maximilian Hamm; Martin Jutzi; Myung-Jin Kim; Ekkehard Kührt; Lucille Le Corre; Guy Libourel; Roy Lichtenheldt; Alessandro Maturilli; Scott R. Messenger; Tatsuhiro Michikami; Hideaki Miyamoto; Stefano Mottola; Akiko M. Nakamura; Thomas Müller; Larry R. Nittler; Kazunori Ogawa; Tatsuaki Okada; Ernesto Palomba; Naoya Sakatani; Stefan Schröder; Hiroki Senshu; Driss Takir; Michael E. Zolensky

arXiv · 1804.03734

Asteroid Ryugu Before the Hayabusa2 Encounter

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Abstract

Asteroid (162173) Ryugu is the target object of Hayabusa2, an asteroid exploration and sample return mission led by Japan Aerospace Exploration Agency (JAXA). Ground-based observations indicate that Ryugu is a C-type near-Earth asteroid with a diameter of less than 1 km, but the knowledge of its detailed properties is still very limited. This paper summarizes our best understanding of the physical and dynamical properties of Ryugu based on remote sensing and theoretical modeling. This information is used to construct a design reference model of the asteroid that is used for formulation of mission operations plans in advance of asteroid arrival. Particular attention is given to the surface properties of Ryugu that are relevant to sample acquisition. This reference model helps readers to appropriately interpret the data that will be directly obtained by Hayabusa2 and promotes scientific studies not only for Ryugu itself and other small bodies but also for the Solar System evolution that small bodies shed light on.

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Koji Wada, Matthias Grott, Patrick Michel, Kevin J. Walsh, Antonella M. Barucci, Jens Biele, Jürgen Blum, Carolyn M. Ernst, Jan T. Grundmann, Bastian Gundlach, Axel Hagermann, Maximilian Hamm, Martin Jutzi, Myung-Jin Kim, Ekkehard Kührt, Lucille Le Corre, Guy Libourel, Roy Lichtenheldt, Alessandro Maturilli, Scott R. Messenger, Tatsuhiro Michikami, Hideaki Miyamoto, Stefano Mottola, Akiko M. Nakamura, Thomas Müller, Larry R. Nittler, Kazunori Ogawa, Tatsuaki Okada, Ernesto Palomba, Naoya Sakatani, Stefan Schröder, Hiroki Senshu, Driss Takir, Michael E. Zolensky. 2018-04-10. Asteroid Ryugu Before the Hayabusa2 Encounter. https://arxiv.org/abs/1804.03734

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