After the successful completion of its Moon mission, China’s Chang’e 2 probe departed lunar orbit on June 9, 2011, and began its trip to asteroid 4179 Toutatis. After a brief layover at the Sun-Earth L2 Lagranian point, Chang’e 2 executed its flyby of the asteroid on Dec. 13, 2012.
The flyby itself was a short one, returning about 400 photos in 25 minutes. They revealed that Toutatis is nearly 3 miles (4.75 kilometers) long and 1.2 miles (1.95 km) wide, making it fairly oblong. (The Scientific Reports paper about the mission calls it “ginger-shaped.”) It is also made up of two lobes, indicating that the asteroid is a contact binary, and has a rubble-pile structure. The successful mission has implications for planetary defense against near-Earth objects, and made China the fourth space agency – following the U.S., Europe, and Japan – to have visited an asteroid.
