Enceladus

Evidence That A Novel Type Of Satellite Wake Might Exist In Saturn's E Ring

By Keith Cowing
astro-ph.EP
May 12, 2021
Filed under
Evidence That A Novel Type Of Satellite Wake Might Exist In Saturn's E Ring
Comparisons of E-ring images with numerical simulations, adapted from Mitchell et al. (2015). The left panels show high-pass filtered and brightness inverted versions of two images of the E ring around Enceladus. The middle and right panels show two different simulations of material recently ejected from Enceladus, with different assumptions about Enceladus’ activity. Two concentrations of material near Enceladus are marked as the Interior and Leading Tendrils. (Note the direction of orbital motion is counterclockwise in the top image and clockwise in the bottom image). For both observations, the leading tendril extends closer to Enceladus in the images than it does in the simulations, so that it is more prominent between the two dotted horizontal lines.

Saturn’s E ring consists of micron-sized particles launched from Enceladus by that moon’s geological activity. A variety of small-scale structures in the E-ring’s brightness have been attributed to tendrils of material recently launched from Enceladus.

However, one of these features occurs at a location where Enceladus’ gravitational perturbations should concentrate background E-ring particles into structures known as satellite wakes. While satellite wakes have been observed previously in ring material drifting past other moons, these E-ring structures would be the first examples of wakes involving particles following horseshoe orbits near Enceladus’ orbit.

The predicted intensity of these wake signatures are particularly sensitive to the fraction E-ring particles’ on orbits with low eccentricities and semi-major axes just outside of Enceladus’ orbit, and so detailed analyses of these and other small-scale E-ring features should place strong constraints on the orbital properties and evolution of E-ring particles.

M.M. Hedman, M. Young

Comments: 18 pages, 10 figures, accepted for publication in PSJ
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2105.05294 [astro-ph.EP] (or arXiv:2105.05294v1 [astro-ph.EP] for this version)
Submission history
From: Matthew Hedman
[v1] Tue, 11 May 2021 18:44:03 UTC (10,913 KB)
https://arxiv.org/abs/2105.05294

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