The Perseverance rover by NASA has been able to detect on the surface of Mars complex carbon molecules which can point towards signatures of microbial life on the red planet that was present in ancient times.
With the help of the Sherloc instrument, organic carbon was identified in the Bright Angel outcrop mudstones. This was done while the rover was in the Neretva Vallis, which was once a river that billions of years ago, carried water to the Jezero crater.
The carbon that has been found here is referred to as macromolecular carbon, or MMC. This carbon is found in living organisms. However, geological processes over millions of years could also be behind this material.
An expert at the Planetary Science Institute in Arizona told news outlet The Guardian, “It may originate from biological sources such as fossilised organic matter found in microbial mats and coal."
The other possibility of this formation could be the chemical reaction between rocks and water or from meteorites that have crashed in the region.
2024 revelations
In 2024, the Bright Angel outcrop became the centre of attention of both scientists and space enthusiasts after Perseverance discovered spots and nodules on the rocks which appeared to be similar to features found on Earth that have occurred due to fossilised microbes.
When details regarding the same was published in 2025, Sean Duffy, who was the former NASA acting head, had remarked that “This very well could be the clearest sign of life that we’ve ever found on Mars.”
The new discovery by Perseverance comes in the wake of a similar discovery made by the Curiosity rover. Thus, these organic-bearing stones have now been located in the red planet around 2,000 miles apart, indicating that the habitability of Mars, and the availability of organics, may have been widespread across the planet billions of years ago” as per authors of the research who have published the same in Science Advances.
Tests need to be done on Earth
A planetary scientist at the University of Leicester, Professor John Bridges, told The Guardian regarding the study, “We can already see that Jezero was a habitable environment for any primitive life, with not just textures hinting at the possibility of life at Bright Angel but the relics of carbon building blocks that would be present if life had existed in this ancient delta.”
The rovers that NASA sent to Mars are not equipped with nailing down the cause behind the complex carbon structures, and this can only be done back on Earth.
Dr Kyle Uckert, one of the co-authors of this paper, has said, “The science payload of the Perseverance rover was not designed to distinguish between organics formed via abiotic and biotic processes but was instead selected to identify compelling rocks to be collected for possible return to Earth for more rigorous testing,” adding, “The best way to determine the biogenicity of these rocks is to conduct these follow-up analyses on Earth.”
