Sample collection from asteroid (162173) Ryugu by Hayabusa2: Implications for surface evolution.

Tomokatsu Morota Seiji Sugita Yuichiro Cho M Kanamaru Eri Tatsumi Naoya Sakatani Rie Honda Naoyuki Hirata H Kikuchi Manabu Yamada Yasuhiro Yokota Shingo Kameda Moe Matsuoka Hirotaka Sawada Chikatoshi Honda Toru Kouyama Kazunori Ogawa Hidehiko Suzuki Kazuo Yoshioka Masahiko Hayakawa Naru Hirata Masatoshi Hirabayashi H Miyamoto Tatsuhiro Michikami Takahiro Hiroi R Hemmi Olivier S Barnouin Carolyn M Ernst Kohei Kitazato Tomoki NakamuraL RiuHiroki Senshu H Kobayashi S Sasaki Goro KomatsuN TanabeY FujiiT IrieM Suemitsu N Takaki C Sugimoto K Yumoto M Ishida H Kato K Moroi Deborah L Domingue Patrick Michel Cedric Pilorget Takahiro Iwata Masanao Abe M Ohtake Y Nakauchi K Tsumura Hikaru Yabuta Yoshiaki Ishihara Rina Noguchi Koji Matsumoto Akira Miura Noriyuki Namiki Shogo Tachibana Masahiko Arakawa Hitoshi Ikeda Koji Wada T Mizuno C Hirose Satoshi Hosoda O Mori T Shimada Stefania Soldini Ryudo Tsukizaki Hajime Yano Masanobu Ozaki Hiroshi Takeuchi Yukio Yamamoto Tatsuaki Okada Yuri Shimaki Kei ShiraiY IijimaHirotomo Noda Shota Kikuchi T Yamaguchi Naoko Ogawa Go Ono Yuya Mimasu Kento Yoshikawa T Takahashi Yuto Takei Atsushi Fujii Satoru Nakazawa Fuyuto TeruiS TanakaMakoto Yoshikawa Takanao Saiki Sei'ichiro Watanabe Yuichi Tsuda

Published in: Science (New York, N.Y.) (2020)

The near-Earth asteroid (162173) Ryugu is thought to be a primitive carbonaceous object that contains hydrated minerals and organic molecules. We report sample collection from Ryugu's surface by the Hayabusa2 spacecraft on 21 February 2019. Touchdown images and global observations of surface colors are used to investigate the stratigraphy of the surface around the sample location and across Ryugu. Latitudinal color variations suggest the reddening of exposed surface material by solar heating and/or space weathering. Immediately after touchdown, Hayabusa2's thrusters disturbed dark, fine grains that originate from the redder materials. The stratigraphic relationship between identified craters and the redder material indicates that surface reddening occurred over a short period of time. We suggest that Ryugu previously experienced an orbital excursion near the Sun.

Keyphrases

deep learning