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Gravitational vortices and clump formation in Saturn's F ring during an encounter with Prometheus.

ABSTRACT: Saturn rings are most beautiful and dynamic places in the solar system, consisting of ice particles in a constant battle between the gravitational forces of Saturn and its many moons. Fan, spiral, propellers, moonlets and streamer-channels observed by CASSINI in the F-ring have been attributed to encounters by Prometheus on the F ring, with investigations of optical thickness revealing large populations of transient moonlets. Taking into account gravitational interaction between particles and a multi-stranded F-ring structure we show that Prometheus' encounters create rotational flows, like atmospheric vortices and the self-gravity enhances the accelerated growth and size of moonlets. Vortex patches form caustics, which is a primary cause of the transient particle density clumps of 20?km width and 100?km length, and they are elongated to cover an area of 1600?km by 150?km, which may eventually combine into a vortex sheet.

SUBMITTER: Sutton PJ

PROVIDER: S-EPMC3572473 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Gravitational vortices and clump formation in Saturn's F ring during an encounter with Prometheus.

Sutton Phil J PJ Kusmartsev Feodor V FV

Scientific reports 20130101

Saturn rings are most beautiful and dynamic places in the solar system, consisting of ice particles in a constant battle between the gravitational forces of Saturn and its many moons. Fan, spiral, propellers, moonlets and streamer-channels observed by CASSINI in the F-ring have been attributed to encounters by Prometheus on the F ring, with investigations of optical thickness revealing large populations of transient moonlets. Taking into account gravitational interaction between particles and a ...[more]

PMID: 23429480

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