Caption: 
Adaptive optics images of asteroid (21) Lutetia obtained at the W.M. Keck Observatory. Here Lutetia is shown at nine different times during the night of Dec. 2, 2008, UT. The scale is in pixels of the Keck camera, which are 0.01 arcsecond in size. These images are not processed to improve clarity.

Credit: 
Credit: Dr. Al Conrad (Keck Observatory)/Dr. Jack Drummond (Starfire Optical Range)/Dr. William Merline (Southwest Research Institute)