With the help of NASA's Spitzer Space Telescope, a team of American astronomers has discovered a new ring of debris surrounding Saturn, so large that it would take a billion Earths to fill it .
Until now, the record for size in the Solar System has been held by Saturn's E ring , a 300,000-kilometer-wide diffuse disk of icy material fed by the moon Enceladus. However, the new disk far exceeds it, since its diameter could exceed 36 million kilometers .
The material in the ring appears to come from the moon Phoebe , which orbits Saturn at a distance equivalent to 215 times the radius of the planet. The astronomers, who publish their discovery tomorrow in the journal Nature , suspect that when this satellite is hit by space rocks, the impacts generate debris that goes to the giant ring.
