Dataset Information

Dark microbiome and extremely low organics in Atacama fossil delta unveil Mars life detection limits.

ABSTRACT: Identifying unequivocal signs of life on Mars is one of the most important objectives for sending missions to the red planet. Here we report Red Stone, a 163-100 My alluvial fan-fan delta that formed under arid conditions in the Atacama Desert, rich in hematite and mudstones containing clays such as vermiculite and smectites, and therefore geologically analogous to Mars. We show that Red Stone samples display an important number of microorganisms with an unusual high rate of phylogenetic indeterminacy, what we refer to as "dark microbiome", and a mix of biosignatures from extant and ancient microorganisms that can be barely detected with state-of-the-art laboratory equipment. Our analyses by testbed instruments that are on or will be sent to Mars unveil that although the mineralogy of Red Stone matches that detected by ground-based instruments on the red planet, similarly low levels of organics will be hard, if not impossible to detect in Martian rocks depending on the instrument and technique used. Our results stress the importance in returning samples to Earth for conclusively addressing whether life ever existed on Mars.

SUBMITTER: Azua-Bustos A

PROVIDER: S-EPMC9944251 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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Dark microbiome and extremely low organics in Atacama fossil delta unveil Mars life detection limits.

Azua-Bustos Armando A Fairén Alberto G AG González-Silva Carlos C Prieto-Ballesteros Olga O Carrizo Daniel D Sánchez-García Laura L Parro Victor V Fernández-Martínez Miguel Ángel MÁ Escudero Cristina C Muñoz-Iglesias Victoria V Fernández-Sampedro Maite M Molina Antonio A Villadangos Miriam García MG Moreno-Paz Mercedes M Wierzchos Jacek J Ascaso Carmen C Fornaro Teresa T Brucato John Robert JR Poggiali Giovanni G Manrique Jose Antonio JA Veneranda Marco M López-Reyes Guillermo G Sanz-Arranz Aurelio A Rull Fernando F Ollila Ann M AM Wiens Roger C RC Reyes-Newell Adriana A Clegg Samuel M SM Millan Maëva M Johnson Sarah Stewart SS McIntosh Ophélie O Szopa Cyril C Freissinet Caroline C Sekine Yasuhito Y Fukushi Keisuke K Morida Koki K Inoue Kosuke K Sakuma Hiroshi H Rampe Elizabeth E

Nature communications 20230221 1

Identifying unequivocal signs of life on Mars is one of the most important objectives for sending missions to the red planet. Here we report Red Stone, a 163-100 My alluvial fan-fan delta that formed under arid conditions in the Atacama Desert, rich in hematite and mudstones containing clays such as vermiculite and smectites, and therefore geologically analogous to Mars. We show that Red Stone samples display an important number of microorganisms with an unusual high rate of phylogenetic indeter ...[more]

PMID: 36810853

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Dataset Information

Dark microbiome and extremely low organics in Atacama fossil delta unveil Mars life detection limits.

Publications

Dark microbiome and extremely low organics in Atacama fossil delta unveil Mars life detection limits.

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