NASA - National Aeronautics and Space Administration

This three-dimensional image of a trough in the Nili Fossae region of Mars shows a type of minerals called phyllosilicates (in magenta and blue hues) concentrated on the slopes of mesas and along canyon walls. The abundance of phyllosilicates shows that water played a sizable role in changing the minerals of a variety of terrains in the planet's early history.

Image credit: NASA/JPL/JHUAPL/University of Arizona/Brown University.

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