Tumbling through space, a peanut-shaped asteroid named 4179 Toutatis is expected to pass within a million miles (1.6 million kilometers) of Earth on Wednesday.
Radar images of the three-mile-long (4.6-kilometer-long) asteroid suggest it could be composed of two or three space rocks held together by gravity.
This approach is the closest in this century of any known asteroid at least as big as Toutatis.

Asteroid Close Encounter Coming Wednesday