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A UNESCO World Heritage Site, Tassili n'Ajjer National Park covers nearly 28,000 square miles as part of the Sahara Desert in southeastern Algeria. This composite image, created back in 2000, was made using multiple photographs taken by NASA's Landsat 7 satellite. The final image is multicolored because Landsat shot a variety of infrared, visible light and near-infrared photographs to "better distinguish between the park's various rock types," according to NASA

"Sand appears in shades of yellow and tan," NASA explained. "Granite rocks appear brick red. Blue areas are likely salts. As the patchwork of colors suggests, the geology of Tassili n'Ajjer is complex. The plateau is composed of sandstone around a mass of granite."

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Image: NASA.

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