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 x 1.95 km) +/- 10%, respectively, and the direction of the +z axis is estimated to be (250 +/- 5 degrees, 63 +/- 5 degrees) 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.
WOS标题词:
Science & Technology
类目[WOS]:
Multidisciplinary Sciences
研究领域[WOS]:
Science & Technology - Other Topics
关键词[WOS]:
RADAR OBSERVATIONS
; BINARY ASTEROIDS
; PHYSICAL MODEL
; CONTACT BINARY
; SPIN STATES
; 21 LUTETIA
; INERTIA
; IMAGES
; EROS
1.China Acad Space Technol, Beijing 100094, Peoples R China 2.Chinese Acad Sci, Key Lab Planetary Sci, Purple Mt Observ, Nanjing 210008, Jiangsu, Peoples R China 3.Inst Space Syst Engn, Beijing 100094, Peoples R China 4.Beijing Inst Control Engn, Beijing 100190, Peoples R China 5.Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China 6.Macau Univ Sci & Technol, Space Sci Inst, Taipa, Macau, Peoples R China 7.Beijing Inst Technol, Beijing 100081, Peoples R China 8.Harbin Inst Technol, Harbin 150001, Peoples R China 9.Peking Univ, Sch Elect Engn & Comp Sci, Beijing 100871, Peoples R China 10.Beijing Inst Space Mech & Elect, Beijing 100076, Peoples R China 11.Natl Cent Univ, Inst Astron, Tao Yuan, Taiwan 12.Planetary Sci Inst, Tucson, AZ 85719 USA 13.Chinese Acad Sci, Yunnan Astron Observ, Kunming 650011, Peoples R China