If you've spent any time looking at the average satellite image of Mars, you'd be forgiven for concluding that our nearest planetary neighbour is actually just one gigantic sandy wasteland. But as this close-up image of the Aureum Chaos proves, Martians don't just hide in the sand.
The Aureum Chaos is a light-toned deposit some 370km wide in the Valles Marineris. The area is pockmarked with canyons, around a kilometre deep, most likely formed by fluid motion — quite possibly ground water discharges — sometime in the past.
Minerals in the ground give it the light colour seen in this image, captured earlier this year by the High Resolution Imaging Science Experiment aboard the Mars Reconnaissance Orbiter.