Babbage from The Economist (subscriber edition) Life on Mars: how promising are the latest findings?
Sep 17, 2025
Join Katie Stack Morgan, project scientist for NASA's Perseverance rover, and Sanjeev Gupta, planetary geologist, as they dive into the thrilling discovery of a potential biosignature on Mars. They discuss the significance of the Sapphire Canyon findings and the complex geology of the 'spotty rocks.' Oliver Morton offers insights into the challenges of bringing samples back to Earth, including funding hurdles and political intrigues. The conversation unpacks how this discovery could reshape our understanding of life beyond Earth!
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Perseverance's Fourfold Mission
- Perseverance's mission had four goals: study geology, seek ancient life, cache samples, and prepare for humans.
- The rover's instruments and sample caching were designed to enable future Earth-based analysis.
Unassuming Rock Hides Complex Textures
- The Sapphire Canyon (Chiava Falls) mudstone held two micro-scale features: vivianite 'poppy seeds' and 'leopard spots'.
- These textures and minerals suggest complex water‑driven chemistry in an ancient river channel.
Mineral Chemistry Points Toward Biology
- Vivianite and the observed rings form when water, iron and organics interact; on Earth microbes often mediate this.
- The team finds abiotic explanations weak given the rock context, elevating a possible biological origin.