NASA says its Perseverance rover has collected what it describes as the first pure sample of Martian clay minerals, drilling into an ancient river delta in Jezero Crater. The core is notable for its unusually high concentration of smectite clays, which are known on Earth for their ability to trap and preserve organic material.

The sample came from a geological setting that scientists consider one of the most promising places to study Mars' watery past. Ancient deltas can concentrate fine sediments and may preserve evidence of conditions that existed billions of years ago, when liquid water was present on the planet’s surface.

Researchers say this discovery could help them better understand whether Mars once had environments capable of supporting life. While the sample does not prove life existed, it may offer a better chance of detecting chemical traces that have survived over time.

Perseverance continues to collect and cache samples that could one day be returned to Earth for detailed laboratory analysis. Those future tests may provide the most definitive answers yet about Mars' history and its potential for habitability.