From the ground, in an everyday rush, it's easy to forget that the landscapes beneath our civilization are part of an epic geological narrative. But through the perspective-altering intervention of satellite imagery, that narrative is revealed, as in this photograph of sand dunes in Idaho's Snake River valley.

The dunes were formed 10,000 years ago, when the last Ice Age ended and what is now eastern Idaho warmed, causing lakes to shrink and exposing sediments carried aloft by wind until hitting a line of extinct volcanoes. The sands accumulated at their base, forming crescent-shaped dunes with tips pointing in the ancient wind's direction.

Taken by NASA's EO-1 satellite, the photograph underscores what's so marvelous about both geology and Earth imagery from space: They expand consciousness in time.

"A sense of time is the most important thing to get across to a non-geologist," said tectonicist Eldridge Moores of the University of California, Davis in John McPhee's Assembling California. "A million years is a small number on the geological time scale, while human experience is truly fleeting — all human experience, from its beginning, not just one timeline."

Image: NASA

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Brandon Keim'sTwitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on an ecological tipping point project.