20 November 2004
Both the north and south polar ice caps overlie a thick accumulation of layered material. For more than three decades, these deposits have been assumed to consist of a mixture of dust and ice. This October 2004 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows some of the north polar layers exposed on a slope located near 79.1°N, 348.4°W. The image covers an area approximately 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.