NASA‘s Perseverance rover, currently exploring Mars’ Jezero Crater, has detected carbon-based molecules that may hint at ancient life on the Red Planet. These findings, reported last summer, were made using SHERLOC (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals), an advanced instrument capable of identifying potential organic compounds. While the discovery has raised hopes within the scientific community, questions about its accuracy remain, as researchers consider alternative explanations for the data. Detection of Organic Molecules and Its Challenges The SHERLOC instrument utilises two techniques: ultraviolet luminescence and Raman spectroscopy. Dr Ken Farley, Project Scientist for the Perseverance mission, explained that SHERLOC can detect organic matter potentially present in Mars’ environment. Luminescence, while highly sensitive, lacks specificity, as non-organic materials can also produce similar signals. Raman spectroscopy provides more precise chemical fingerprints, but its sensitivity is limited. This combination allows researchers to hypothesise about the presence of organic molecules, but uncertainties in the data complicate definitive conclusions. Potential Alternative Explanations A study published in Science Advances posited that the detected signals could originate …