Sept. 9, 2004 — Images sent back to Earth by the Cassini spacecraft reveal aspects of Saturn scientists have never seen: another moon — possibly two — and a ring of material.

While studying the contorted F ring, a region of the planet's rings that mystifies scientists, Carl Murray, imaging team member at Queen Mary, University of London, spied a small object orbiting just at the edge of the ring, according to a NASA press release.

"I noticed this barely detectable object skirting the outer part of the F ring. It was an incredible privilege to be the first person to spot it," he said.

Murray's group at Queen Mary then calculated an orbit for the object.

It's not clear whether the moon, named S/2004 S3, actually is a moon or a clump of matter that will ultimately break apart, said the press release.

It's also not clear whether there are one or two objects. While trying to pin down the moon's orbit, Joseph Spitale, a planetary scientist at the Space Science Institute in Boulder, Colo., spied something odd.

"When I went to look for additional images of this object to refine its orbit, I found that about five hours after first being sighted, it seemed to be orbiting interior to the F ring," said Spitale. "If this is the same object, then it has an orbit that crosses the F ring, which makes it a strange object."

As a result, the inner object sighted by Spitale is being considered a separate object, called S/2004 S4. If the two objects turn out to be a single moon, it will bring the Saturn moon count to 34.

Murray also detected the new ring while examining the F ring.

"We knew from Voyager that the region between the main rings and the F ring is dusty, but the role of the moons in this region was a mystery," said Murray in the press release. "It was while studying the F ring in these images that I discovered the faint ring of material.

"My immediate hunch was that it might be associated with the orbit of one of Saturn's moons, and after some calculation I identified Atlas as the prime suspect," he said.

The ring is located 138,000 kilometers (86,000 miles) from the center of Saturn in the orbit of the moon Atlas, between the A ring and the F ring. It's not yet known whether it extends all the way around the planet.

Cassini team leader Carolyn Porco at the Space Science Institute said: "We have planned many images to search the region between the A and F rings for diffuse material and new moons, which we have long expected to be there on the basis of the peculiar behavior of the F ring. Now we have found something but, as is usual for the F ring, what we see is perplexing."