Overview

• An international team reports in Nature that a 2024 Perseverance sample dubbed “Sapphire Canyon” contains grains of iron phosphate and iron sulfide associated with organic carbon.
• The material comes from Bright Angel mudstones in Jezero’s ancient river–lake system, pointing to a once-habitable setting roughly 3.5 billion years ago.
• NASA labels the mineral–organic associations as potential biosignatures, with officials describing a “potential fingerprint” of past microbes that remains unconfirmed.
• Researchers caution that non-biological pathways could produce the same features, and the result sits at the first step of NASA’s CoLD confidence scale.
• Confirmation depends on Mars Sample Return, which has slipped beyond 2030 as alternatives are studied and China targets a Tianwen-3 sample-return attempt in 2028.