The Cassini spacecraft observed three of Saturn's moons set against the darkened night side of the planet in this image from April 2011.
Saturn is present on the left this image but is too dark to see. Rhea (1,528 kilometers, or 949 miles across) is closest to Cassini here and appears largest at the center of the image. Enceladus (504 kilometers, or 313 miles across) is to the right of Rhea. Dione (1,123 kilometers, or 698 miles across) is to the left of Rhea, and is partly obscured by Saturn.
This view looks toward the northern, sunlit side of the rings from just above the ringplane.
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