Overview

• A Nature paper reports organic carbon co-located with vivianite and greigite in Bright Angel mudstones, arranged in concentric reaction fronts nicknamed “leopard spots.”
• Perseverance’s SHERLOC detected a Raman G-band signal for organics with the strongest responses at a site called Apollo Temple, while PIXL and X-ray mapping established the minerals’ spatial relationships.
• The textures and mineral associations point to redox cycling consistent with microbially influenced processes on Earth, yet the authors stress the signal remains a potential biosignature rather than proof of life.
• Abiotic routes requiring sustained high heat or strong acidity appear inconsistent with the observed rock history, according to mission scientists, increasing interest in laboratory tests on returned samples.
• Perseverance’s July 2024 Sapphire Canyon core is prioritized for possible return, and separate studies suggest ESA’s Rosalind Franklin rover at Oxia Planum could access organic-rich materials delivered by rockfalls and ancient floods.