NASA scientists have travelled to Scotland to study rocks that may hold clues about the history of water on Mars.

The team examined the Stoer formation, a set of 1.2-billion-year-old rocks on Scotland's northwest coast. These rocks formed in ancient lakes and rivers, making them a good match for places NASA studies on Mars.

On Earth, geologists can walk around the rocks and see the full landscape. On Mars, rovers like Perseverance see only small areas. The Scottish site helps scientists learn how to read the clues.

NASA says the work supports evidence of repeated water activity on Mars. Perseverance has found interesting features at the edge of an ancient lakebed.

Mars was once much wetter than it is today. Understanding when and where water flowed helps scientists judge whether the planet could once have supported life.

The research shows how fieldwork on Earth directly supports space exploration. The lessons from Scotland will guide how NASA reads data from the Red Planet.