The varying temperatures of Saturn's rings are depicted here in this false-color NASA image from the Cassini spacecraft. (NASA/AFP/Getty Images)
The faint ring, made of tiny particles, partly marks the orbit of Saturn's distant moon Phoebe, Anne Verbiscer of the University of Virginia and colleagues reported Wednesday in the journal Nature.
Phoebe, orbits the ringed planet at a radius of about 8 million miles and, evidently, objects colliding with Phoebe and kicking up dust keep the ring supplied with material.
"The closest analogs to the Phoebe ring are the two gossamer rings associated with Jupiter's inner satellites, Thebe and Amalthea," they wrote. These moons, too, are the source of dust kicked up by collisions.
"Similar structures should also adorn the other gas giant planets," the researchers added.
Galileo first potted Saturn's colorful rings in 1610 with his telescope, and almost any amateur planet-spotter can see the densest of the giant planet's rings.
Verbiscer's team used NASA's Spitzer Space Telescope to see this new one, which is very deep, lies far beyond Saturn's other rings and is tilted at a 27-degree angle to the plane of the others.
"This is one supersized ring," Verbiscer said in a statement.
Saturn, Jupiter, Uranus and Neptune all have rings.
