This image is a composite mosaic of four polar views of Mars taken by NASA's Mars Reconnaissance Orbiter spacecraft and released on October 16. This is possible because during summer the sun is always shining in the polar region.
It shows the mostly water-ice perennial cap (white area), sitting atop the north polar layered materials (light tan immediately adjacent to the ice), and the dark circumpolar dunes.
(China Daily via agencies October 17, 2006)