Press release: Clues to detecting life on Mars
No. 96 - 16.07.2026
International research team develops new criteria in search for finding life on Mars
The search beyond Earth for traces of life is one of the key challenges facing modern planetary science. An international research team, including researchers from the University of Göttingen, has investigated what kind of clues might be left behind on the Red Planet by microscopic organisms – and demonstrated just how difficult it is to reach a clear interpretation of these. The results were published in the Geological Society of America Bulletin.
The team analysed iron-rich “microbialites” – sedimentary structures on Earth which are formed by microorganisms. Such structures are among the oldest evidence of life on Earth. The samples come from the Río Tinto in south-west Spain – a location with extremely acidic, iron-rich conditions, that may have been common on the surface of early Mars at certain times. It is therefore possible that comparable sedimentary structures could also exist on the Red Planet – and these could have potentially been formed by life during periods when liquid water was present. Until now, however, it was unclear what criteria must be met in order to reliably identify microbialites as part of ongoing Mars missions.
The researchers’ investigations included microbial communities as well as the structure and chemical composition of the microbialites. Their findings showed that many features that could indicate the presence of life do not, on their own, allow for any clear conclusions to be drawn about biological processes. This means that currently no clear biological signatures can be detected using the instruments on today’s Mars rovers.
“The problem is that similar structures can also form without microorganisms,” explains Professor Jan-Peter Duda at Göttingen University’s Department of Geobiology, who carried out the study with his former research group at Tübingen University before moving to Göttingen. The group remains active there. A single characteristic is therefore not sufficient to draw definitive conclusions about biological processes: the team emphasises that indicators such as mineral composition, organic carbon content or iron isotopes do not, on their own, allow for clear conclusions about such biological processes. “Other particularly significant indicators, such as microbial cells, DNA or growth rates, cannot, however, be reliably detected using the instruments on today’s Mars rovers,” said Professor Andreas Kappler at Tübingen University’s Geomicrobiology Research Group.
The study highlights the importance of bringing actual rock samples from Mars back to Earth. Here, they can be analysed using a wide range of independent methods and carefully compared with known terrestrial traces of microbial life.
Original Publication: Pei, Y. et al. Iron microbialites from an acidic Martian analog (Río Tinto, Spain) – Implications for finding life on Mars. Geological Society of America Bulletin (2026). DOI: 10.1130/B38599.1
Contact:
Professor Jan-Peter Duda
University of Göttingen
Faculty of Geoscience and Geography – Department of Geobiology
Goldschmidtstraße 3, 37077 Göttingen, Germany
Tel: +49 (0) 551 39-27922
Email: jan-peter.duda@uni-goettingen.de
uni-goettingen.de/en/643536.html
Professor Andreas Kappler
University of Tübingen
Department of Geosciences – Geomicrobiology Research Group
Schnarrenbergstrasse 94–96, 72076 Tübingen, Germany
Tel: +49 (0)7071 29-74992