This image is a closeup of the newly discovered moon of the asteroid Ida, provisionally designated '1993 (243) 1.' This is a magnified, processed version of the single view of the natural satellite transmitted so far by the Galileo spacecraft to Earth. Only 1.5 kilometers (1 mile) across in this view, the overall shape, size, rotation and orbital motion of the natural satellite are still unknown. The sun's illumination is coming from the upper right. The black 'gouge' in the body's shape toward the lower left is probably more apparent than real and is mostly a part of the shadowed night side of the little moon. A rugged landscape, including one or two craters, appears to be present, although the smallest features that can be detected in this picture are about 1/7th the diameter of the natural satellite. This picture was taken by Galileo during its flyby of Ida on August 28, 1993. Later in the spring of 1994, scientists hope to receive other views of Ida's moon which are currently stored on Galileo's onboard tape recorder; one of those images is expected to be at least three times sharper than this one. The Jet Propulsion Laboratory manages the Galileo Project for NASA's Office of Space Science.
Voir l'image PIA00299: Early View of Dactyl sur le site de la NASA.This image is the most detailed picture of the recently discovered natural satellite of asteroid 243 Ida taken by the Galileo Solid-State Imaging camera during its encounter with the asteroid on August 28, 1993. Shuttered through the camera's broadband clear filter as part of a 30-frame mosaic designed to image the asteroid itself, this frame fortuitously captured the previously unknown moon at a range of about 3,900 kilometers (2,400 miles), just over 4 minutes before the spacecraft's closest approach to Ida. Each picture element spans about 39 meters (125 feet) on the surface of the moon. More than a dozen craters larger than 80 meters (250 feet) in diameter are clearly evident, indicating that the moon has suffered numerous collisions from smaller Solar System debris during its history. The larger crater on the terminator is about 300 meters (1,000 feet) across. The satellite is approximately egg-shaped, measuring about 1.2 x 1.4 x 1.6 kilometers (0.75 x 0.87 x 1 mile). At the time this image was shuttered, Ida was about 90 kilometers (56 miles) away from the moon, outside this frame to the left and slightly below center. This image was relayed to Earth from Galileo on June 8, 1994. The Galileo project, whose primary mission is the exploration of the Jupiter system in 1995-97, is managed for NASA's Office of Space Science by the Jet Propulsion Laboratory.
Voir l'image PIA00297: High Resolution View of Dactyl sur le site de la NASA.