Probabilistic characterization of lunar lava tube collapses: Implications for reliability-based design, safety, and exploration

Abstract

The study presents the results of over 30,000 numerical analyses on the stability of lava tubes under lunar conditions. The research considered random irregularities in cave geometry and their impact on stability, with a particular focus on the geometric characteristics of identified collapses. We propose a procedure for extracting the collapse areas and integrating it into the stability analysis results. The results were examined to assess the possibility of describing the geometry characteristics of collapses using commonly applied probability density distributions, such as normal or lognormal distribution. Our aim is to facilitate future risk assessment of lunar caves. Such an assessment will be essential prior to robotically exploring caves beneath the lunar surface and can be extended to be used for planetary caves beyond the Moon. Our findings indicate that several collapse characteristics can be represented by unimodal probability density distributions, which could significantly simplify the candidate selection process. Based on our results, we also highlight several key directions for future research and suggested implications related to their future exploration.

Keywords

Lunar caves / Lava tubes / Probabilistic approach / Reliability-based design / Collapse area / Lunar collapse pits

CRediT authorship contribution statement

Marcin Chwała: Writing - original draft, Supervision, Software, Project administration, Methodology, Funding acquisition, Formal analysis, Conceptualization. Kamil Górniak: Writing - review & editing, Software, Methodology, Formal analysis.

Declaration of competing interest

The authors declare that they have no known competing finan-cial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgement

The work was performed based on the research project no. 2023/51/D/ST10/01956, financed by the National Science Center, Poland. The authors would like to thank the two anonymous reviewers, Professor Jut Wynne, and Professor Karoly Nemeth for their helpful comments and suggestions, which have significantly improved the quality of this manuscript.

Appendix A. Supplementary data

Supplementary data to this article can be found online at https://doi.org/10.1016/j.gsf.2025.102076.

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