Original Caption Released with Image:
This montage of 11 images taken by the Galileo spacecraft as it flew by the
asteroid Gaspra on October 29, 1991, shows Gaspra growing progressively
larger in the field of view of Galileo's solid-state imaging camera as the
spacecraft approached the asteroid. Sunlight is coming from the right. Gaspra
is roughly 17 kilometers (10 miles) long, 10 kilometers (6 miles) wide. The
earliest view (upper left) was taken 5 3/4 hours before closest approach when
the spacecraft was 164,000 kilometers (102,000 miles) from Gaspra, the last
(lower right)at a range of 16,000 kilometers (10,000 miles), 30 minutes before
closest approach. Gaspra spins once in roughly 7 hours, so these images
capture almost one full rotation of the asteroid. Gaspra spins
counterclockwise; its north pole is to the upper left, and the 'nose' which
points upward in the first image, is seen rotating back into shadow, emerging
at lower left, and rotating to upper right. Several craters are visible on the
newly seen sides of Gaspra, but none approaches the scale of the asteroid's
radius. Evidently, Gaspra lacks the large craters common on the surfaces of
many planetary satellites, consistent with Gaspra's comparatively recent
origin from the collisional breakup of a larger body. 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 and Applications by the Jet
Propulsion Laboratory.
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Galileo Solid State Imaging Team Leader: Dr. Michael J. S. Belton
The SSI Education and Public Outreach webpages were originally created and
managed by Matthew Fishburn and Elizabeth Alvarez with significant assistance
from Kelly Bender, Ross Beyer, Detrick Branston, Stephanie Lyons, Eileen Ryan,
and Nalin Samarasinha.
Last updated: September 17, 1999, by Matthew Fishburn
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