S/2004 S 4 is the provisional designation of an unconfirmed object seen orbiting Saturn within the inner strand of the F ring on June 21, 2004. It was spotted while J. N. Spitale was trying to confirm the orbit of another provisional object, S/2004 S 3, that was seen 5 hours earlier just exterior to the F ring.[2] The announcement was made on September 9, 2004.[4]
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.[5]
An interpretation where S/2004 S 3 and S/2004 S 4 are or were a single object on a F-ring crossing orbit is also possible.[4] 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 4 would be 3–5 km in diameter based on brightness.
"Cassini Imaging Science Team". Cassini Imaging Central Laboratory for OPerationS. Retrieved 2012-01-01.
Green, Daniel W. E. (September 9, 2004). "S/2004 S 3, S/2004 S 4, and R/2004 S 1" (discovery). IAU Circular. 8401: 1. Bibcode:2004IAUC.8401....1P. Retrieved 2012-01-01.
Martinez, Carolina; Ormrod, Gill; Finn, Heidi (September 9, 2004). "Cassini Discovers Ring and One, Possibly Two, Objects at Saturn". jpl.nasa.gov. NASA Jet Propulsion Laboratory. Retrieved 2012-01-01.
Spitale, J. N.; Jacobson, R. A.; Porco, C. C.; Owen, W. M., Jr. (2006). "The orbits of Saturn's small satellites derived from combined historic and Cassini imaging observations". The Astronomical Journal. 132 (2): 692–710. Bibcode:2006AJ....132..692S. doi:10.1086/505206.{{cite journal}}: CS1 maint: multiple names: authors list (link)
August 22, 2023
2004, provisional, designation, unconfirmed, object, seen, orbiting, saturn, within, inner, strand, ring, june, 2004, spotted, while, spitale, trying, confirm, orbit, another, provisional, object, 2004, that, seen, hours, earlier, just, exterior, ring, announc. S 2004 S 4 is the provisional designation of an unconfirmed object seen orbiting Saturn within the inner strand of the F ring on June 21 2004 It was spotted while J N Spitale was trying to confirm the orbit of another provisional object S 2004 S 3 that was seen 5 hours earlier just exterior to the F ring 2 The announcement was made on September 9 2004 4 S 2004 S 4DiscoveryDiscovered byCICLOPS Team 1 2 Discovery dateJune 21 2004Orbital characteristics 3 Semi major axis 140 100 kmEccentricityunknown smallOrbital period sidereal 0 618 dInclinationunknown smallSatellite ofSaturnGroupF RingPhysical characteristicsMean radius 2 kmSynodic rotation periodprobably synchronousAxial tiltunknownAlbedounknownDespite 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 5 An interpretation where S 2004 S 3 and S 2004 S 4 are or were a single object on a F ring crossing orbit is also possible 4 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 4 would be 3 5 km in diameter based on brightness References EditCitations CICLOPS Team a b Martinez Ormrod amp Finn 2004 PGJ Astronomie webpage Gilbert Javaux Note that the F ring is centered at 140 180 km a b IAUC 8401 Spitale Jacobson et al 2006 Sources Cassini Imaging Science Team Cassini Imaging Central Laboratory for OPerationS Retrieved 2012 01 01 Green Daniel W E September 9 2004 S 2004 S 3 S 2004 S 4 and R 2004 S 1 discovery IAU Circular 8401 1 Bibcode 2004IAUC 8401 1P Retrieved 2012 01 01 Martinez Carolina Ormrod Gill Finn Heidi September 9 2004 Cassini Discovers Ring and One Possibly Two Objects at Saturn jpl nasa gov NASA Jet Propulsion Laboratory Retrieved 2012 01 01 Spitale J N Jacobson R A Porco C C Owen W M Jr 2006 The orbits of Saturn s small satellites derived from combined historic and Cassini imaging observations The Astronomical Journal 132 2 692 710 Bibcode 2006AJ 132 692S doi 10 1086 505206 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link Retrieved from https en wikipedia org w index php title S 2004 S 4 amp oldid 1144694177, wikipedia, wiki, book, books, library,
