LunaIcy: Exploring Europa's Icy Surface Microstructure through Multiphysics Simulations

TL;DR

LunaIcy is a multiphysics simulation model that investigates how heat transfer influences ice microstructure evolution on Europa, revealing that short-term temperature spikes can lead to significant sintering in the icy surface.

Contribution

This study introduces the first coupled heat transfer and sintering simulation model for planetary ice, providing new insights into Europa's surface microstructure evolution.

Findings

Sintering occurs where daily temperatures exceed 115 K.

Effective sintering can happen within timescales shorter than Europa's ice crust age.

Europa's surface likely consists of an interconnected ice structure due to sintering.

Abstract

A multiphysics simulation model incorporating a sintering model coupled with the MultIHeaTS thermal solver was developed to study the evolution of icy moons' microstructure. The sintering process is highly dependent on temperature, and this study represents the first attempt in planetary science to examine the coupled interaction between heat transfer and sintering. Our approach to ice sintering is based upon the literature while offering a refined description of the matter exchange between grains, bonds, and the pore space. By running the numerical framework, we simulate the evolution of ice microstructure on Galilean satellites, specifically tracking the changes in the ice grain and bond radii over time. LunaIcy, our multiphysics model, was applied to study the evolution of Europa's ice microstructure over 1 million yr along its orbit, with a parameter exploration to investigate the diverse configurations of the icy surface. Our results indicate that effective sintering can take place in regions where daily temperatures briefly surpass 115 K, even during short intervals of the day. Such sintering could not have been detected without the diurnal thermal coupling of LunaIcy due to the cold daily mean temperature. In these regions, sintering occurs within timescales shorter than Europa's ice crust age, suggesting that, in present times, their surface is made of an interconnected ice structure.