Physical collisions of moonlets and clumps with the Saturn's F-ring core

Sebastien Charnoz

doi:10.1016/j.icarus.2008.12.036

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arXiv · 0901.0482

Physical collisions of moonlets and clumps with the Saturn's F-ring core

Sebastien Charnoz

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Abstract

Since 2004, observations of Saturn's F ring have revealed that the ring's core is surrounded by structures with radial scales of hundreds of kilometers, called "spirals" and "jets". Gravitational scattering by nearby moons was suggested as a potential production mechanism; however, it remained doubtful because a population of Prometheus-mass moons is needed and, obviously, such a population does not exist in the F ring region. We investigate here another mechanism: dissipative physical collisions of kilometer-size moonlets (or clumps) with the F-ring core. We show that it is a viable and efficient mechanism for producing spirals and jets, provided that massive moonlets are embedded in the F-ring core and that they are impacted by loose clumps orbiting in the F ring region, which could be consistent with recent data from ISS, VIMS and UVIS. We show also that coefficients of restitution as low as ~0.1 are needed to reproduce the radial extent of spirals and jets, suggesting that collisions are very dissipative in the F ring region. In conclusion, spirals and jets would be the direct manifestation the ongoing collisional activity of the F ring region.

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Sebastien Charnoz. 2009-01-05. Physical collisions of moonlets and clumps with the Saturn's F-ring core. https://doi.org/10.1016/j.icarus.2008.12.036

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