This first image of asteroid 951 Gaspra was taken by the Galileo spacecraft on October 29, 1991, from a distance of 16,200 kilometers (10,000 miles).
The Sun is shining from the right. The illuminated part of the asteroid is about 16 by 12 kilometers (10 by 7.5 miles). The surface shows many craters; two large facets about 8 kilometers (5 miles) across appear on the limb of the asteroid at top and bottom right. The smallest craters in this view are about 300 meters (1,000 feet) across.
Gaspra rotates in a counter-clockwise direction in just over 7 hours; its north pole is near the upper left corner of the lighted part of the asteroid.
The Galileo project, whose primary mission is the exploration of the Jupiter system in 1995-1997, is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory. Image Credit: NASA/JPL