Saturn's supersized ring uncovered

The faint ring extends more than seven million miles from the planet.

The faint ring has remained hidden until now but is enormous, extending out more than seven million miles from the planet.

Unlike Saturn's "flat" rings, the new belt resembles a thick halo of material. Its vertical height is about 20 times the planet's diameter.

The ring, made from a ice and dust particles, was spotted by the Spitzer space telescope which captured its infrared glow.

Dr Anne Verbiscer, one of the US astronomers from the University of Virginia in Charlottesville, said: "This is one supersized ring. If you could see the ring, it would span the width of two full moons' worth of sky, one on either side of Saturn."

The ring is associated with one of Saturn's moons, Phoebe, which is believed to supply it with material.

The discovery, reported in the journal Nature, may help solve an age-old riddle concerning one of Saturn's moons.

Iapetus has one side that is bright while its other face is strangely dark.

Scientists now believe the dark side of Iapetus may be due to dusty material from the newly found outer ring slamming into its surface. Iapetus and the outer ring circle Saturn in opposite directions, so that debris shed by the ring is likely to collide with the moon.

Spitzer was launched by the American space agency Nasa in 2003 and is now 66 million miles from the Earth in orbit around the Sun.

The telescope has an infrared camera which can pick up long-wavelength light that is invisible to the naked eye.

It was able to sense the glow of the cool dust making up the ring, which has a temperature of minus 158C.