This mosaic of images from the Spirit rover, taken on Sol 1925 (June 2, 2009), helped engineers assess the rover's state and plan Spirit's extraction from the soft soil at the site called "Troy." The images were taken by Spirit's microscopic imager instrument, mounted on the end of the robotic arm.
This is the first time the microscopic imager has been used to assist in planning a rover's escape from an embedding event. The imager isn't intended to take these types of images; it is designed to focus on targets only 6 centimeters (2.4 inches) in front of its optics. As a result, the images in this mosaic are well out of focus. Yet despite the focus and the backlighting of the scene, the mosaic is still very useful for helping to assess the situation. The mosaic is rotated to show the true orientation of the rover relative to the local terrain. The view shows the underside of the rover, the depth to which the wheels are embedded, and the terrain itself in sufficient detail.
