Astrobiologists from the Universities of Edinburgh and Oxford reviewed evidence of all known processes that could have produced natural deposits in rocks on Mars.
They recognized dozens of procedures– with much more likely still undiscovered– that can produce structures that simulate those of microscopic, simple lifeforms that may when have existed on Mars.
Amongst the natural specimens these processes can produce are deposits that look like bacterial cells and carbon-based particles that closely resemble the foundation of all understood life.
Since indications of life can be so closely simulated by non-living processes, the origins of any fossil-like specimens found on Mars are likely to be extremely ambiguous, the group says.
They require greater interdisciplinary research study to shed more light on how natural deposits could form on Mars, and thus aid the look for evidence of ancient life there and in other places in the planetary system.
The research is released in the Journal of the Geological Society.
Dr. Sean McMahon, Chancellors Fellow in Astrobiology at the University of Edinburghs School of Physic and Astronomy, said: “At some stage a Mars rover will nearly definitely find something that looks a lot like a fossil, so being able to with confidence differentiate these from compounds and structures made by chemical reactions is essential. For every single type of fossil out there, there is at least one non-biological process that develops very comparable things, so there is a genuine need to improve our understanding of how these type.”
Julie Cosmidis, Associate Professor of Geobiology at the University of Oxford, stated: “We have been fooled by life-mimicking processes in the past. On lots of events, objects that appeared like fossil microbes were explained in ancient rocks on Earth and even in meteorites from Mars, but after much deeper assessment they ended up to have non-biological origins. This short article is a cautionary tale in which we call for more research study on life-mimicking procedures in the context of Mars, so that we prevent falling under the exact same traps over and over again.”
Reference: “False biosignatures on Mars: anticipating uncertainty” by Sean McMahon and Julie Cosmidis, 17 November 2021, Journal of the Geological Society.DOI: 10.1144/ jgs2021-050.
Julie Cosmidis, Associate Professor of Geobiology at the University of Oxford, said: “We have actually been fooled by life-mimicking procedures in the past. On lots of occasions, items that looked like fossil microorganisms were described in ancient rocks on Earth and even in meteorites from Mars, however after deeper evaluation they turned out to have non-biological origins. This post is a cautionary tale in which we call for additional research study on life-mimicking procedures in the context of Mars, so that we prevent falling into the very same traps over and over again.”
Composite image showing some of the types of fossil-like specimens produced by chemical reactions that could be found on Mars. Credit: Sean McMahon, Julie Cosmidis and Joti Rouillard
Mars explorers looking for indications of ancient life could be tricked by fossil-like specimens produced by chemical processes, research suggests.
Rocks on Mars might contain many kinds of non-biological deposits that look comparable to the kinds of fossils likely to be found if the world ever supported life, a research study states.
Informing these false fossils apart from what could be proof of ancient life on the surface area of Mars– which was temporarily habitable 4 billion years back– is essential to the success of future and present objectives, researchers say.
