Spirit took this front hazard-avoidance camera image on sol 37 (Feb. 9, 2004) after completing the longest drive ever made by a rover on another planet - 21.2 meters (69.6 feet). The wavy feature called a bedform is created when material is transported and deposited by some process - in this case wind. The team is interested in the fact that the crests of this and most other bedforms they've observed through orbital data and rover images are all parallel to each other, indicating uniform wind direction.