Subsurface life can modify volatile cycling on a planetary scale.

GIOVANELLI D.; BARRY P.; BEKAERT D.; CHIODI AGOSTINA; CORDONE G.; COVONE G.; JESSEN G.; LLOYD K.; DE MOOR M.; MORRISON M.; SCHRENK M.; VITALE BROVARONE A.

Memorie della Societa Astronomica Italiana

Istituto Nazionale di Astrofisica

Lugar: Roma; Año: 2021 vol. 92

1824-016X

The past decade of environmental microbiology has revealed that subsurfaceenvironments, both marine and continental, harbor one of the largest ecosystems of ourplanet, with diversity and biomass rivaling those of the surface. In addition, subsurface lifehas been recently shown to contribute significantly to the planet?s biogeochemistry, with microbialactivity potentially playing an important role in controlling the flux and compositionof volatiles recycled between the Earth?s surface and interior, which has broad implicationsfor the search for life beyond our planet. Current eorts to discover extraterrestrial lifeare focused on planetary bodies with largely inhospitable surfaces, such as Mars, Venus,Europa, Titan, and Enceladus. In these locations, subsurface environments might provideniches of habitability, making the study of deep microbial life a priority for future astrobiologicalmissions. Understanding how volatile elements are exchanged between planetarysurfaces and interiors and the role of a subsurface biosphere in altering their compositionand flux might provide a tractable target for defining planetary habitability and the detectionof subsurface life forms.