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SMALL BODIES it highly improbable any alternative interpretation for those structures. They cannot, for example, re- present traces of cometary activity such as that observ- ed on Chiron. On the contrary, those sec- ondary events perfectly suit the interpretation that saw the two rings reach the more favourable inclina- tion for their visibility (60°) in 1996-97, and presented, instead, edgewise to us in 2008 (in keeping with the relative orbital motion of Chariklo and Earth). This scenario provides the sim- plest possible explanation for the aforementioned photometric variability of the asteroid and for the dis- appearance-reappearance of the absorption band of water ice, element that evidently dominates the rings and falls below the threshold of visibility when the same are not visible (since edgewise). If we assume that the photometric variabil- ity of the Chariklo system is entirely attribu- table to the geometric variations of the rings, it follows that their albedo (surface reflectivity) is about 0.09, a value higher than that of the asteroid and of the rings of Uranus (0.05), but lower than that of Sat- I n the diagram above we can see how the var- ious observers recorded the stel- lar occultation in which Chariklo had the leading role. The green segments repre- sent the most re- liable recordings (their length is proportional to the margin of error) [F. Braga- Ribas et al.] In the video: re- presentation of the occultation seen from a par- ticularly favour- able position. [ESO/L. Calçada] urn’s A-ring (0.3). Depending on the thick- ness that’s attributed to Chariklo’s rings and on the models adopted to interpret its evo- lution, we find out that their existence should last anywhere from a few thousand to a few million years. Consequently, either they are very young structures or acting upon them there is a confinement mecha- nism similar to that of Saturn’s F-ring, but in this case provided by a “shepherd” satel- lite with a mass comparable to that of the same rings. So far no satellite has been discovered in or- bit around Chariklo, but the assumption is plausible, given that at least 5% of Cen- taurs host satellites. In addition to the is- sue of the long per- sistence of the rings, there is also another, no less important, mat- ter to solve. How did they form? Braga-Ribas and col-