Mars From Afar
Polar Gas Channels
Known informally as a "spider," the topographic feature seen in this
image of Mars' south polar region represents a process not found on
Earth. The branching tendrils contain carbon dioxide gas, which
flows through the channels until it reaches a vent; it then escapes
to the atmosphere, carrying dust with it. The tendrils, appearing
bright-white with the carbon dioxide ice that covers the poles
during winter, weave into the surrounding icy terrain, which, in
turn, is blanketed by the region's characteristic reddish-brown
dust. The image was taken on March 24, 2007, by the High Resolution
Imaging Science Experiment.