Microbial studies in the lava tubes on Earth: overview and implications for astrobiology

Abstract:

As an interdisciplinary subject combined with deep space exploration, astrobiology studies the habitability of extraterrestrial planets by the analogical study of the extreme environments on Earth, the exploration of carrier information of ancient life, and simulation. Notably, suitable environmental conditions are crucial for evaluating the habitability of planets. Recently, a large number of lava landforms suspected of lava tubes have been found on the Moon and planets such as Mars. These giant tube-shaped underground spaces may provide shelters for life to survive in consideration of the relative stable temperature inside and the function of radiation protection. Therefore, the analogical studies based on lava tubes on Earth can provide fundamental clues for exploring the traces of extraterrestrial life. Here, we review the microbial studies about the lava tubes on Earth, the implications of microbial metabolism of trace gas for astrobiology, and the recent progress in astrobiology, aiming to provide ideas for astrobiological research on lava tubes on Earth and other planets.