关于这张图
A field of sand dunes occupies this frosty 5-kilometer diameter crater in the high-latitudes of the northern plains of Mars. Some dunes have separated from the main field and appear to be climbing up the crater slope along a gully-like form. The surface of the main dune field is characterized by a series of dark-toned polygonal patterns. These may be the result of seasonal frost processes. Several of the steeper dune slopes, pointing in the downwind direction, host narrow furrows suggesting the start of gully formation. The crater floor contains a variety of textures, including lobate and st…