NASA's Discovery of Signs of Life on Mars (2025)

The National Aeronautics and Space Administration's (NASA) discovery of a potential biosignature on Mars (2025) is associated with the “Sapphire Canyon” sample collected by the Perseverance rover from the Cheyava Falls rock in Jezero Crater. The mineralogical and structural features observed in this sample are being evaluated as a potential biosignature. The findings were published in the journal Nature in 2025 and officially announced to the public by NASA on 10 September 2025.

Summary of the Discovery

The Perseverance rover landed in Jezero Crater in 2021. The Sapphire Canyon sample, collected in July 2024 from the Cheyava Falls rock within the Bright Angel formation, has emerged as one of the most significant findings. This sample was published as a scientific paper in 2025 and assessed as a potential biosignature.

Research Area: Jezero Crater and Neretva Vallis

Jezero Crater was once a water-filled region featuring a lake and delta system. Neretva Vallis, located along the crater’s edge, is a river valley approximately 400 metres wide. The Bright Angel formation consists of rocky outcrops along the edge of this valley, with Cheyava Falls being a part of this formation.

Cheyava Falls is a fine-grained, rust-red mudstone measuring approximately one metre by 0.6 metres. The Sapphire Canyon sample was taken from this rock. Analyses revealed the presence of organic carbon, phosphorus, sulfur and oxidized iron within the rock.

Structural Features: Poppy Seeds and Leopard Spots

Dark small spots on the surface of Cheyava Falls have been nicknamed “poppy seeds.” Larger ring-shaped patterns are described as “leopard spots.” These structures are interpreted as mineral reaction fronts.

Cheyava Falls refers to the rock under study; Sapphire Canyon is the name of the collected sample. Bright Angel denotes the rocky outcrops along the edge of Neretva Vallis.

The minerals vivianite (hydrated iron phosphate) and greigite (iron sulfide) have been identified in the rock sample. These minerals may have formed as a result of electron transfer reactions between organic matter and sediments. On Earth, similar minerals are frequently observed in sedimentary environments influenced by microbial processes.

Measurement Instruments and Method

Mineralogical and chemical analyses were conducted using the PIXL and SHERLOC instruments aboard Perseverance. High-resolution imaging enabled the detection of mineral reaction fronts. To date, the mission has collected 27 core samples sealed in tubes.

The reactions observed in the rock are believed to have occurred shortly after deposition in the lakebed. The aqueous environments of Jezero Crater have been dated to between 3.2 and 3.8 billion years ago. The findings suggest that biosignatures may be preserved in relatively young sedimentary rocks.

Definition of a Potential Biosignature

A potential biosignature is defined as a structure or substance that could have a biological origin but requires additional evidence to confirm it as definitive proof of life. The scientific community evaluates such findings using systems such as the CoLD scale and evidence standards.

Leopard Spots on the Reddish Rock Known as “Cheyava Falls” in Jezero Crater on Mars (NASA)

The co-occurrence of organic carbon, sulfur, phosphorus and oxidized iron in the same rock may have created suitable energy sources for microbial metabolism. On Earth, vivianite and greigite are commonly associated with microbial processes in freshwater lakes, swamps and sedimentary environments.

Vivianite and greigite can also form through non-biological processes. High temperatures and acidic conditions are among the abiotic scenarios proposed. However, no evidence of such conditions has been found in the Bright Angel rocks. Therefore, a definitive biological explanation cannot yet be established.

NASA’s Statements

NASA officials have emphasized that the findings do not constitute direct evidence of life but rather indicate a potential biosignature. They have reiterated the principle that extraordinary claims require extraordinary evidence.

Acting NASA Administrator Sean Duffy has stated that the structures observed in the sample taken from Cheyava Falls could represent the strongest potential biosignature yet discovered on Mars. Duffy noted that the data have been evaluated for approximately one year, that non-biological explanations appear limited, and therefore that the finding holds extraordinary significance. However, he emphasized that his statement does not constitute definitive evidence of life.

Perseverance Rover (NASA)

Perseverance Project Chief Scientist Katie Stack Morgan stated that the findings must be classified at the level of a “potential biosignature.” Morgan emphasized that astrobiological claims require extraordinary evidence, that the current data point more strongly toward biological explanations, but that abiotic scenarios cannot be ruled out.

NASA Associate Administrator for Science Mission Directorate Nicky Fox stressed that the findings do not equate to evidence of life itself. Fox explained that the concept of a potential biosignature requires additional data and analysis, and therefore the results must be interpreted with caution. She also noted that the data published in the paper have been made publicly available, allowing independent researchers to examine them and verify the conclusions.

Research continues with laboratory experiments on Earth to test the plausibility of non-biological processes.