In this image from NASA’s Cassini probe, Saturn’s A and F rings appear bizarrely warped where they intersect the planet’s limb, whose atmosphere acts here like a very big lens.
In its upper regions, Saturn’s atmosphere absorbs some of the light reflected by the rings as it passes through. But absorption is not the only thing that happens to that light. As it passes from space to the atmosphere and back out into space towards Cassini’s cameras, its path is refracted, or bent. The result is that the ring’s image appears warped.
This view looks toward the sunlit side of the rings from about 18 degrees above the ring plane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on 9 June 2016.
The view was acquired at a distance of approximately 1.8 million kilometres (1.1 million miles) from the rings and at a Sun-rings-spacecraft, or phase, angle of 112 degrees. Image scale is 11 kilometres (7 miles) per pixel.
Saturn: Exploring the Ringed Planet
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