According to a recent report based on some of the first observations by NASA's Mars Reconnaissance Orbiter, fluids that flowed through cracks penetrating underground rock on ancient Mars may have produced conditions to support possible habitats for microbial life.
Dr. Chris Okubo, a geologist at the University of Arizona, Tucson, discovered the patterns in an image of exposed layers in a Martian canyon named Candor Chasma. The image was taken in September 2006 by the High Resolution Imaging Science Experiment camera aboard the orbiter.
The haloes visible along fractures seen in the Candor Chasma image appear to be slightly raised relative to surrounding, darker rock. This is evidence that the circulating fluids hardened the lining of the fractures, as well as bleaching it. The harder material would not erode away as quickly as softer
material farther from the fractures.
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For the images showing the haloes along the fractures, click here.