Radar Images of Asteroid 4179 Toutatis

Abstract

Delay-Doppler images of the Earth-crossing asteroid 4179 Toutatis achieve resolutions as fine as 125 nanoseconds (19 meters in range) and 8.3 millihertz (0.15 millimeter per second in radial velocity) and place hundreds to thousands of pixels on the asteroid, which appears to be several kilometers long, topographically bifurcated, and heavily cratered. The image sequence reveals Toutatis to be in an extremely slow, non-principal axis rotation state.