From Scientific American:
A diffuse, newfound ring encircles the gas giant planet at an extraordinary distance.
A speculative search for a belt of debris stemming from one of Saturn's outer moons has turned up what appears to be the largest known planetary ring in the solar system.
The newfound ring, associated with the far-flung moon Phoebe, stretches to roughly 12.5 million kilometers from Saturn, if not more, according to a paper announcing the finding in this week's Nature. (Scientific American is part of the Nature Publishing Group.) For comparison, the outer bound of Saturn's next largest known ring, the E ring, is less than half a million kilometers from the planet.
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