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- This animation consists of 11 images taken by the Galileo
- spacecraft as it flew by the asteroid 951 Gaspra on October 29, 1991.
- The animation 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 first frame of the animation (smallest image) was taken
- 5 3/4 hours before closest approach when the spacecraft was 164,000
- kilometers (102,000 miles) from Gaspra, the last frame (largest image)
- 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.
-