"NASA's Spitzer Space Telescope has discovered an enormous ring around Saturn -- by far the largest of the giant planet's many rings.The new belt lies at the far reaches of the Saturnian system, with an orbit tilted 27 degrees from the main ring plane. The bulk of its material starts about six million kilometers (3.7 million miles) away from the planet and extends outward roughly another 12 million kilometers (7.4 million miles). One of Saturn's farthest moons, Phoebe, circles within the newfound ring, and is likely the source of its material.
Saturn's newest halo is thick, too -- its vertical height is about 20 times the diameter of the planet. It would take about one billion Earths stacked together to fill the ring."
In other Saturn news, "In mid-August, Saturn passed through its equinox and sunlight shone directly along the rings, so that even the most subtle vertical structure cast long shadows. Images from the Cassini spacecraft revealed that the planet's C ring has a gentle corrugation that extends across tens of thousands of kilometers. The ripples are barely 100 meters high and recur with a wavelength varying from 30 kilometers toward the planet to 80 kilometers farther out... What's more, the pattern seems to be evolving with time, its wavelength steadily diminishing. Extrapolating back in time, it must have been set in motion 25 years ago...It looks like the ring—the whole ring—was abruptly yanked out of Saturn's equatorial plane... he suggests that it wasn't the ring that shifted, but Saturn's equatorial plane. A tilt of a thousandth of a degree would suffice...In other words, the entire planet Saturn suddenly lurched in the mid-1980s...What must have happened instead is that mass shifted within the planet, reorienting the effective gravitational equator."
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