Discovery | |
---|---|
Discovered by | CICLOPS Team [1] |
Discovery date | June 21, 2004 |
Orbital characteristics [2] [3] [4] | |
140,100–140,600 km | |
Eccentricity | < 0.002 [a] |
0.62 d | |
Inclination | close to zero |
Satellite of | Saturn |
Group | F Ring |
Physical characteristics | |
Mean radius | ~2 km |
probably synchronous | |
unknown | |
Albedo | unknown |
S/2004 S 3 is the provisional designation of an object seen orbiting Saturn just beyond the outer strand of the F ring on June 21, 2004. It was discovered by the Cassini Imaging Science Team in images taken by the Cassini–Huygens probe on June 21, 2004 [4] and announced on September 9, 2004. [5]
Despite later attempts to recover it, it has not been reliably sighted since. Notably, an imaging sequence covering an entire orbital period at 4 km resolution taken on November 15, 2004 failed to recover the object. The sequence should have been easily capable of detecting a moon of similar size, suggesting it to simply be a transient clump. An approximate linkage could be made of S/2004 S 3 to S/2004 S 4, and matched to two other detected clumps on other dates, but considering its non-detection in November, their relation is probably coincidental. [2]
Another object, S/2004 S 4, was sighted nearby 5 hours later, but this time just inside the F Ring. Because of the differing localisation the second object was given a fresh designation, although their interpretation as a single object on a F-ring crossing orbit is also possible. [5] Such an object might also be orbiting at a slightly different inclination to the F ring, thereby not actually passing through the ring material despite being seen both radially inward and outward of it.
If a solid object after all, S/2004 S 3 would be 3–5 km in diameter based on brightness, and might be a shepherd satellite for the outer edge of Saturn's F ring.
Explanatory
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