Photo by NASA on Unsplash (illustrative)
On 10 September 2025, NASA announced that a rock sample collected by its Perseverance rover in July 2024 contains a potential biosignature, a possible trace of past life that still needs more study. The findings, led by Joel Hurowitz of Stony Brook University, were published in the journal Nature.
Key facts
The sample, named 'Sapphire Canyon', was drilled from a rock called 'Cheyava Falls' in an ancient river valley in Jezero Crater.
The rock's mudstone contains organic carbon and tiny spots rich in two iron minerals, vivianite and greigite, formed by low-temperature chemical reactions.
These minerals can also form without life, for example through high heat or acidic conditions, but the rocks show no sign of either.
NASA defines a potential biosignature as a substance or structure that might have a biological origin but needs more data before life can be confirmed or ruled out.
Why it matters
Whether life ever existed beyond Earth is one of science's biggest questions. The Nature study concludes that laboratory analysis of the collected rock will be needed to settle where its minerals and organic matter came from, which makes this sample a prime target for future study.
Worth noting
A potential biosignature is not proof of life. NASA's project scientist said non-living explanations are less likely but cannot be ruled out, and in a survey only about 15% of astrobiologists said life had probably been found.