title: The ginger-shaped asteroid 4179 Toutatis: new observations from a successful flyby of Chang'e-2.
abstract: On 13 December 2012, Chang'e-2 conducted a successful flyby of the near-Earth asteroid 4179 Toutatis at a closest distance of 770 ± 120 meters from the asteroid's surface. The highest-resolution image, with a resolution of better than 3 meters, reveals new discoveries on the asteroid, e.g., a giant basin at the big end, a sharply perpendicular silhouette near the neck region, and direct evidence of boulders and regolith, which suggests that Toutatis may bear a rubble-pile structure. Toutatis' maximum physical length and width are (4.75 × 1.95 km) ±10%, respectively, and the direction of the +z axis is estimated to be (250 ± 5°, 63 ± 5°) with respect to the J2000 ecliptic coordinate system. The bifurcated configuration is indicative of a contact binary origin for Toutatis, which is composed of two lobes (head and body). Chang'e-2 observations have significantly improved our understanding of the characteristics, formation, and evolution of asteroids in general.
authors: 1] China Academy of Space Technology, Beijing 100094, China [2] Institute of Space System Engineering, Beijing 100094, China [3].
authors: Jiangchuan
authors: J
authors: Huang
authors: 1] Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China [2].
authors: Jianghui
authors: J
authors: Ji
authors: China Academy of Space Technology, Beijing 100094, China.
authors: Peijian
authors: P
authors: Ye
authors: Beijing Institute of Control Engineering, Beijing 100190, China.
authors: Xiaolei
authors: X
authors: Wang
authors: National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China.
authors: Jun
authors: J
authors: Yan
authors: Institute of Space System Engineering, Beijing 100094, China.
authors: Linzhi
authors: L
authors: Meng
authors: Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China.
authors: Su
authors: S
authors: Wang
authors: National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China.
authors: Chunlai
authors: C
authors: Li
authors: Space Science Institute, Macau University of Science and Technology, Taipa, Macau.
authors: Yuan
authors: Y
authors: Li
authors: Beijing Institute of Technology, Beijing 100081, China.
authors: Dong
authors: D
authors: Qiao
authors: Harbin Institute of Technology, Harbin 150001, China.
authors: Wei
authors: W
authors: Zhao
authors: Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China.
authors: Yuhui
authors: Y
authors: Zhao
authors: China Academy of Space Technology, Beijing 100094, China.
authors: Tingxin
authors: T
authors: Zhang
authors: Harbin Institute of Technology, Harbin 150001, China.
authors: Peng
authors: P
authors: Liu
authors: Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China.
authors: Yun
authors: Y
authors: Jiang
authors: Institute of Space System Engineering, Beijing 100094, China.
authors: Wei
authors: W
authors: Rao
authors: School of Electronic Engineering and Computer Science, Peking University, Beijing 100871, China.
authors: Sheng
authors: S
authors: Li
authors: Beijing Institute of Space Mechanics and Electricity, Beijing 100076, China.
authors: Changning
authors: C
authors: Huang
authors: 1] Space Science Institute, Macau University of Science and Technology, Taipa, Macau [2] Institute of Astronomy, National Central University, Taoyuan, Taiwan.
authors: Wing-Huen
authors: WH
authors: Ip
authors: Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China.
authors: Shoucun
authors: S
authors: Hu
authors: Space Science Institute, Macau University of Science and Technology, Taipa, Macau.
authors: Menghua
authors: M
authors: Zhu
authors: Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China.
authors: Liangliang
authors: L
authors: Yu
authors: National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China.
authors: Yongliao
authors: Y
authors: Zou
authors: Harbin Institute of Technology, Harbin 150001, China.
authors: Xianglong
authors: X
authors: Tang
authors: Planetary Science Institute, AZ 85719, USA.
authors: Jianyang
authors: J
authors: Li
authors: Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China.
authors: Haibin
authors: H
authors: Zhao
authors: Institute of Space System Engineering, Beijing 100094, China.
authors: Hao
authors: H
authors: Huang
authors: National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China.
authors: Xiaojun
authors: X
authors: Jiang
authors: Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011, China.
authors: Jinming
authors: J
authors: Bai