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tokens: not removed, but their orbits were significantly changed due to a significant perturbation caused by an encounter with a giant planet. In Figure 2 , we present an example of the effects of such an encounter with Jupiter. The plots show the maximum final variation in semimajor axis and eccentricity among the hundred particles that share the same initial radial position. As expected, the values increase with the radial distance. In the region of the rings (indicated by the vertical lines) the semimajor axis changes by more than 30 km and the eccentricity grows up to more than 0.5. Figure 2. An example of a disturbing close encounter caused on the ring by a close encounter with Jupiter. (a) Maximum final change in eccentricity. (b) Maximum final change in semimajor axis (km). The plots show the maximum final changes among the hundred particles that share the same initial radial position. The vertical lines indicate the boundary of the ring region. The encounter was performed with a minimum distance of 6.6 planet radii, with a relative velocity of km s −1 . The encounter resulted in a critical radius of R C = 460 km, meaning that no particles in the region of the rings were removed. The results of the encounters that produced at least some noticeable variations (Δ e ≥ 0.01) on the orbits of the rings are presented in Table 4 for backward and forward integrations, excluding the encounters followed by ejection. Table 4 List of Significant Disturbing Encounters (Δ e ≥ 0.01) with the Giant Planets for both Forward and Backward Integration within the Time Span of 10 Myr Notes. The immediate ejection cases were excluded. a The minimum encounter distance given in terms of the radius of the planet in question. b Survival time after a disturbing encounter. For the forward integration, we observed only five encounters with Jupiter and two with Saturn that resulted in eccentricities larger than 0.1 for the ring particles. None of the encounters with Uranus or Neptune showed significant orbital variation of the particles of the rings. Similarly, if we look backward, we see fewer close encounters that could have increased the eccentricity of the particles of the rings for values larger than 0.1 (five with Jupiter, one with Saturn, and one with Uranus). Since Chariklo, as observed now, has well-defined narrow circular rings (Braga-Ribas et al. 2014 ), this might mean that it did not suffer any of these disturbing encounters or, if they did occur, it was so long ago that the rings had time to evolve, damping the eccentricity and reshaping the rings. Both possibilities are compatible with our results and, as shown in Table 3 , the probability of catastrophic or disturbing encounters is very low, and probably occurred several million years ago. 7. THE EJECTION CASES The close encounters of Chariklo with any of the giant planets followed by ejections are particularly interesting. If we look forward, these would be the encounters responsible for removing Chariklo