Click on the image to download the full sized jpeg image. The images were obtained when Galileo was in Jupiter's shadow, peering back toward the Sun. Since the spacecraft was located only about 0.15 degrees above the ring plane at the time, the images are highly foreshortened in the vertical direction.
North is to the bottom.
The white vertical crescent at the left is caused by sunlight filtering through Jupiter's upper atmosphere. The right panel, taken at the greatest sensitivity, shows a tenuous horizontal stripe, which can also be made out in the middle panel. Jovian moon, and has a half-thickness that is the same as Amalthea's maximum excursion off Jupiter's equatorial plane.