Knowledge Gaps in our Understanding of the Mechanisms Governing Heat Transport in Regolith at Low Temperatures

Permanently shadowed areas (PSAs) on, e.g., the Moon or Mercury, can show surface temperatures down to 30 K (Martinez & Siegler 2021) and can act as cold traps for water ice. At such cryogenic temperatures, water ice will be stable over geological timescales and PSAs are therefore of high interest for in-situ resource utilization (ISRU) efforts due to the potential of finding stable ice in the shallow subsurface. To better understand the ice deposition process and to better predict water ice stability, reliable models using realistic material parameters are needed. At cryogenic temperatures (