Lava tubes as subsurface shelters against micrometeorites

Lava tubes as subsurface shelters against micrometeorites or habitats with nearly constant temperatures will become an important exploration target. Additionally, they are of scientific relevance as they could host ice deposits and provide access to the underlying bedrock. The presence of lava tubes on the Moon has been inferred based on observed collapsed features and supported by radar measurements.

LUNA has been provided now with a simulated lava tube. When modelling lave tubes often a 3:1 width-to-height ratio and a semi-elliptical cross-section are assumed. A simulated lave tube needs to consist of a stiff coating simulating the lava around the hollow space and providing a significant contrast in geophysical properties compared to the regolith and a simulated hollow space within, which needs to have a significant contrast with the surrounding lava. These features have been simulated in LUNA by a Styrodur supporting structure and the surrounding coating by concrete.