Characterizing Deposits Emplaced By Cryovolcanic Plumes On Europa
In the absence of direct observations of Europa’s particle plumes, deposits left behind during eruptive events would provide the best evidence for recent geological activity, and would serve as indicators of the best places to search for ongoing activity on the icy moon.
Here, we model the morphological and spectral signatures of europan plume deposits, utilizing constraints from recent Hubble Space Telescope observations as model inputs. We consider deposits emplaced by plumes that are 1 km to 300 km tall, and find that in the time between the Galileo Mission and the arrival of the Europa Clipper spacecraft, plumes that are < 7 km tall are most likely to emplace deposits that could be detected by spacecraft cameras. Deposits emplaced by larger plumes could be detected by cameras operating at visible wavelengths provided that their average particle size is sufficiently large, their porosity is high, and/or they are salt-rich.
Conversely, deposits emplaced by large plumes could be easily detected by near-IR imagers regardless of porosity, or individual particle size or composition. If low-albedo deposits flanking lineated features on Europa are indeed cryoclastic mantlings, they were likely emplaced by plumes that were less than 4 km tall, and deposition could be ongoing today. Comparisons of the sizes and albedos of these deposits between the Galileo and Europa Clipper missions could shed light on the size and frequency of cryovolcanic eruptions on Europa.
L.C. Quick, M.M. Hedman
(Submitted on 29 Jan 2020)
Comments: 50 pages, 12 Figures, accepted for publication in Icarus
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2001.10981 [astro-ph.EP] (or arXiv:2001.10981v1 [astro-ph.EP] for this version)
Submission history
From: Matthew Hedman
[v1] Wed, 29 Jan 2020 17:44:38 UTC (1,193 KB)
https://arxiv.org/abs/2001.10981
Astrobiology
