NASA scientists studied ancient rocks in the Scottish Highlands during a 2026 field expedition described in a September 29 update. The team examined landscapes and mineral features that can help scientists interpret evidence collected by Mars rovers.

The work includes reduction spots: features that can be associated with microbial activity but can also form through other processes. Samples collected on Earth allow laboratory investigations that are not possible with rover instruments alone. The photograph shows actual Scottish rock examined in the expedition, rather than a Martian sample.

Source: NASA / Caela Barry.

Image: NASA / Pedro Cota. Actual Scottish reduction-spot sample from the 2026 expedition. Image source · License / usage terms.