Dunes In Winter

The HiRise camera package on the Mars Reconnaissance Orbiter continues to send back stunningly beautiful images of complex and unexpected textures on the Martian surface. The image above, looking like nothing so much as a finely sculptured high-end chocolate dessert, is of dunes inside a crater in the Southern hemisphere. It's currently winter, in the Southern hemisphere of Mars, and the sheen on the smooth east-facing slopes, sheltered from the sun, is either water or carbon dioxide frost. The intricate scrolls and furls of the west-facing slopes is due to modification by southerly and northerly winds of ridges sculpted by prevailing westerly winds.

You can find a high-resolution image, a close-up of the latticed dunes, and more information here; Boston Globe's the Big Picture has a great gallery here. In the past decade, HiRise's vast catalogue of images and images and data from Mars Global Surveyor, Mars Express, the MRO, the two rovers Spirit and Opportunity, and the Phoenix Lander, have rendered every novel and non-fiction book about Mars out-of-date to some degree or other. Time for a new wave, perhaps...