The_Rings-N00191724-N00191763-GB-LXTT-IPF.gifIn the Rings (a GIF-Movie by Dr Gianluigi Barca - Lunar Explorer Italia/Italian Planetary Foundation)95 visiteOnce (actually, only a few decades ago...), we used to think that the Rings of the Gas-Giant Planet Saturn were something unique in the Universe. Now, after we have seen Rings and/or Ring-Arcs and Ringlets around each and every one of the other three Gas-Giant Planets Jupiter, Uranus and Neptune, we do know that the Rings of Saturn are just the Most Extensive (---> i.e.: the Widest) Planetary Ring System in the Solar System. The Rings of Saturn - according to the majority of the Planetary Scientists - mostly consist of countless, small particles of Ice and Dust (ranging, in size, from micrometres to a few metres), which orbit around Saturn. As a matter of fact, the Ring Particles are made almost entirely of Water Ice, with some contamination from Dust and - maybe - other (minor) Elements.
As everybody should know, although reflection from the Rings increases the brightness of Saturn, the Rings themselves are not visible from Earth with unaided vision. In the AD 1610, however (such as one year after the Italian Astronomer Galileo Galilei first turned a telescope to the Sky), the Rings of Saturn appeared in all their beauty and Galileo Galilei became the very first person to observe them, even though he could not see them well enough to discern their true nature. Afterwards, in the AD 1655, the Dutch Mathematician and Astronomer Christiaan Huygens was the first one to describe them as a Disk made by (some kind of) Material surrounding (---> orbiting around) Saturn. Although many people still believe that the Rings of Saturn are made by a series of tiny Ringlets (a concept that goes back to Laplace), it is way more correct to think of them (like some NASA Scientists recently suggested) as an Annular Disk with concentric Local Maxima and Minima in both Density and Brightness. The Rings have numerous Gaps where the Particles' Density drops sharply: two of these Gaps opened because of the action of small (and known) really small moons which are actually "embedded" within them, while many others are located in specific places where the Tidal Forces exercized by (resonating) Saturnian moons create a phenomenon of Gravitational Destabilization of entire regions of the Rings themselves. Stabilizing resonances, on the other hand, can be considered responsible for the stability (and longevity) of several Rings (think about, for instance, to the Titanian Ringlet and the G-Ring). Well beyond the Main Rings, there is the so-called "Phoebe Ring", which is tilted at an angle of 27° as to the other Rings and, just like Phoebe, orbits in a Retrograde fashion.
Furthermore, and just out of Intellectual Curiosity, we wish to highlight that we believe, as IPF, after we examined (in extreme detail) several hundreds of close-up pictures of the Rings which were all obtained during the last Saturnian Equinox, that there should (and could well) be a few (relatively wide) Regions of the Rings themselves that are NOT made by Orbiting Ice and Dust Particles, but rather by orbiting "Pavings", such as by Aggregated Particles of Ring Material that, since they were positioned/located in specific regions within the Rings where they neither did nor do suffer any - or, maybe, just a negligible - Tidal Stress, in time joined together and formed something like "Floating Rocky Slates" (which means, in other words, the "flat" equivalent of a so-called "rubble-pile" Asteroid).MareKromium
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The_Rings-N00191888-N00191985-GB-LXTT-IPF.gifIn the Rings (a GIF-Movie by Dr Gianluigi Barca - Lunar Explorer Italia/Italian Planetary Foundation)101 visiteSince all the Beauties of the Universe in general - as well as many of the ones of our Solar System in particular - cannot always be adequately understood nor explained (and, please, forgive us if and when we say that those who state and declare that today's Science can really explain everything, in our opinion, as IPF, do not have the least idea of what they are talking about...), we have learned that, sometimes, and in front of certain phenomena which, as we just said, are not only impossible to recreate but (and for now), are also impossible to be observed from a REALLY close distance (thus making them extremely difficult to be fully understood and therefore explained in a satisfying way), it is Science itself that calls for some speculation.
This small foreword was absolutely necessary because the very few lines that shall follow (and which relate to the possible origin of Saturn's Rings) are, in our humble opinion, almost pure Scientific Speculation. Yes, of course we know that the hypothesis which we shall try to illustrate do represent an "informed Scientific Speculations", but still we have no actual proof (and, likely, we shall never have it) that even one of them is correct, either in full or just in part.
Given all that, we can start by saying that, according to several (either recent and/or less recent) Theories, the Rings of Saturn should be EXTREMELY old, meaning that they could be dating to the formation of Saturn (as well as of the whole Solar System) itself. Furthermore (and as a matter of fact), nowadays there are just 2 (two) Main Theories regarding the origin of Saturn's Rings which are thought to be sufficiently believable: the first one, originally proposed by the French Astronomer Édouard Robert Roche in the 19th Century, is that the Rings were once a moon of Saturn (named "Veritas", after a Roman Goddess) whose orbit, for (obviously...) unknown reasons, decayed (however, we suggest, as IPF and among many other possibilities, the occurrence of a powerful impact, that was strong enough to disrupt Veritas' orbit but NOT to disintegrate - at least, not entirely - the moon itself), until the moon came close enough to its Parent Planet so to be litterally ripped apart by the Saturnian Tidal Forces (in other words, and assuming that this Theory is basically correct, "Veritas" must have been some sort of a "Rubble-pile moon", such as a Celestial Body which was so fragile that it could not pass the so-called "Roche Limit" without being - almost - completely disintegrated). A variation of this first Main Theory (a variation that, however, we believe - as IPF - to be extremely unlikely) is that the "Veritas" moon simply disintegrated after being struck by a large Comet or an Asteroid.
The second Main Theory is that the Rings of Saturn were never part of a moon, but they are, instead, some physical leftovers of the original Proto-Planatary Nebula (i.e.: Nebular-like Material) from which Saturn itself was formed.MareKromium
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The_Rings-N00191994-N00192059-GB-LXTT-IPF.gifIn the Rings (a GIF-Movie by Dr Gianluigi Barca - Lunar Explorer Italia/Italian Planetary Foundation)97 visiteThe densest Regions of the Saturnian Ring System consist of the A and B-Rings, which are separated by the so-called "Cassini Division" (which was discovered in the AD 1675 by the Italian Astronomer Giovanni Domenico Cassini). Along with the C-Ring, which was discovered 75 years later (such as in the AD 1850), these three Regions together form the Main Rings of the Giant Gas Planet Saturn.
The Main Rings are denser and contain larger Water Ice and Rocky Particles than the very tenuous so-called Dusty Rings, which include the D-Ring (extending inward, towards Saturn's Cloud Tops), the G and E-Rings, as well as other and even more tenuous (or also "diffuse") Rings and Ringlets (and, perhaps, even some Ring Arcs) which are all located beyond the three Main Rings (which can also be named as the "Main Ring System").
These "Diffuse Rings" are known as "dusty" because of the extremely small size of the Water Ice and Dust Particles which form them (and whose size can often be in the order of just one or two micrometers). Last, but not least, the narrow F-Ring - which rotates just off the Outer Edge of the A-Ring - is the most difficult one to be categorized, and that is because some parts of it are very dense, while others are extremely tenuous.
The brightness and purity of the Water Ice contained in the Rings has been often cited as evidence that they should (and could very well be) much younger than Saturn (some Scientists say - but this is, of course, just a speculation - that their age could be of approx. 100 Million Years only, since the infall of Meteoric Dust would have led to some very obvious darkening of the Rings themselves, if they had been older. However, a new research also indicates that the B-Ring may be massive enough to have diluted the infalling Meteoric Dust Material and thus avoided any substantial darkening of the entire Ring System. In addition to the above, the material forming the Rings may also be periodically recycled, as "Clumps" form within the Rings and then are disrupted by occasional Impacts. This last theory, if proven correct, could substantially explain the apparent youth of some of the Material existing within the whole Ring System.
The NASA - Cassini - UVIS Team, led by Dr Larry Esposito, used the so-called "Stellar Occultation Method" to discover something like 13 (thirteen) new Celestial Objects, ranging from approx. 27 metres to about 10 Km across, and all located within the F-Ring. These Objects appear to be translucent, thus suggesting that they could be temporary aggregates of Water Ice Boulders, each one of them being a few meters across. Dr Esposito believes that this could be the Basic (Mechanical) Structure that allows the formation and (somehow periodic) renewal of the entire Saturnian Ring System, such as Water Ice and Rocky Dust Particles first clumping together, and then being - as we suggested, maybe occasionally, maybe periodically - blasted apart.MareKromium
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The_Rings-PIA08298.jpgFrom the Dark Side of Saturn58 visiteCaption NASA:"The Cassini spacecraft gazes down through the Dark Side of Saturn's Rings toward the softly glowing Planet. The night side Southern Hemisphere is lit by Sunlight reflecting off the opposite side of the Rings.
The Planet's shadow slices diagonally across the scene.
This view was acquired from about 23° above the Ring-Plane. The sliver of Saturn's sunlit crescent is partly overexposed as seen through the Cassini Division, a Region where there is less material to block or scatter incoming light.
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were taken with the Cassini spacecraft wide-angle camera on Sept. 11, 2006 at a distance of approx. 1,1 MKM (about 700.000 miles) from Saturn and at a phase angle of 151°.
Image scale is about 60 Km (such as approx. 37 miles) per pixel".
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