This image shows the region on Mars in the vicinity of Gusev Crater. The left part of the image is a grayscale "photo" of the area. The right-hand part of the picture is color-coded to indicate elevations; green represents low places, orange and red indicate higher elevations. The central image is a global view of Mars, centered on 180° W longitude, with the location of Gusev Crater marked. For reference, Gusev Crater is roughly 130 km (81 miles) across; Mars is about 6,794 km (4,222 miles) in diameter.
Images courtesy NASA.