S/2004 S 3
Discovery image of S/2004 S 3
|Discovered by||Carl Murray / Cassini Imaging Science Team|
|Discovered on||21 June, 2004|
|Semimajor axis||140,100 − 140,600 km|
|Eccentricity||< 0.002 |
|Orbital period||0.62 d|
|Inclination||close to zero|
|Is a satellite of||Saturn|
|Mean diameter||3–5 km|
|Rotation period||probably synchronous|
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.
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, S/2004 S 4, 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.
References[change | change source]
- Spitale, J. N.;; et al. (2006). "The orbits of Saturn's small satellites derived from combined historic and Cassini imaging observations". The Astronomical Journal. 132: 692.CS1 maint: extra punctuation (link) CS1 maint: multiple names: authors list (link)
- IAUC 8432: Satellites and Rings of Saturn 2004 November 8 (claiming recovery of S/2004 S 3 on 17 October, 2004, in conflict with the later (2006) Spitale | display-authors = etal)
- Martinez, C; Ormrod, G; and Finn, H.; Cassini Discovers Ring and One, Possibly Two, Objects at Saturn JPL news release (September 9 2004)
- Based on above semimajor axis range, and Spitale | display-authors = etal (2006)
- IAUC 8401: S/2004 S 3, S/2004 S 4, and R/2004 S 1 2004 September 9 (discovery)
Other websites[change | change source]
- 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)