S/2004 S 3

is the designation of an object seen orbiting Saturn just beyond the farther part of the F ring on 21 June, 2004. It was first seen by Carl Murray of the Cassini Imaging Science Team  in pictures taken by the Cassini-Huygens probe on June 21, 2004, and announced on September 9, 2004.IAUC 8401: S/2004 S 3, S/2004 S 4, and R/2004 S 1 2004 September 9 (discovery)

Even though later astronomers tried to find it again, it has not been reliably seen since. Notably, an imaging sequence covering an entire orbital period at 4 km resolution taken on 15 November, 2004 failed to find the object. This suggests that it was a clump of material that had disappeared by that time.

Another object, , was seen nearby 5 hours later, but this time just inside the F Ring. Because of the different location of the second object, it was given a fresh designation, although their interpretation as a single object on a F-ring crossing orbit is also possible. Such an object might also be orbiting at a bit different inclination to the F ring, thereby not actually passing through the ring material even though it was being seen both radially inward and outward of it.

If a solid object after all,  would be 3−5 km in diameter based on brightness, and might be a shepherd satellite for the farther edge of Saturn's F ring.

References

Other websites
 Cassini-Huygens press release about discoveries around the F ring in 2004 
 Cassini-Huygens Multimedia: The Clump/Moon Mystery September 5, 2005 (images of the clumps and/or moons seen around the F ring by Cassini cameras)

Category:Saturn's moons