Enceladus

Particle Deposition On The Saturnian Satellites From Ephemeral Cryovolcanism On Enceladus

By Keith Cowing
Press Release
astro-ph.EP
May 23, 2022
Filed under , , , ,
Particle Deposition On The Saturnian Satellites From Ephemeral Cryovolcanism On Enceladus
The leading hemisphere of Helene (N1687120437) with arrows (located at the centers of triangles of the shape-model) indicating the directions of the local gravity (color represents slopes). Blue lines indicate streaky depressions. The regions enclosed by yellow or red lines are the regions with and without streaky depressions, respectively. Streaky features exist on steeper (> ~7 degree) and strictly follow the directions of surface gravity. Inset shows the total areas of both regions as a function of slope angle (see Table S3 in supporting information). The horizontal axis is a moving average of ±1.5 degree for the total area of the angle ±0.5 degree.

The geologically active south pole of Enceladus generates a plume of micron-sized particles, which likely form Saturn’s tenuous E-ring extending from the orbit of Mimas to Titan.

Interactions between these particles and satellites have been suggested, though only as very thin surficial phenomena. We scrutinize high-resolution images with a newly developed numerical shape model of Helene and find that the leading hemisphere of Helene is covered by thick deposits of E-ring particles, which occasionally collapse to form gully-like depressions. The depths of the resultant gullies and near-absence of small craters on the leading hemisphere indicate that the deposit is tens to hundreds of meters thick.

The ages of the deposits are less than several tens of My, which coincides well with similar deposits found on Telesto and Calypso. Our findings as well as previous theoretical work collectively indicate that the cryovolcanic activity currently occurring on Enceladus is ephemeral.

Naoyuki Hirata, Hideaki Miyamoto, Adam P. Showman

Comments: 23 pages 6 figures
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2205.11265 [astro-ph.EP] (or arXiv:2205.11265v1 [astro-ph.EP] for this version)
Journal reference: Geophysical Research Letters 2014, Volume 41, Issue 12, 4135-4141
Related DOI:
https://doi.org/10.1002/2014GL060470
Focus to learn more
Submission history
From: Naoyuki Hirata
[v1] Mon, 23 May 2022 12:29:13 UTC (1,047 KB)
https://arxiv.org/abs/2205.11265
Astrobiology

SpaceRef co-founder, Explorers Club Fellow, ex-NASA, Away Teams, Journalist, Space & Astrobiology, Lapsed climber.