A natural wonder has baffled scientists and researchers in Death Valley National Park for decades: large boulders seem to mysteriously move across the barren dried lakebed on their own accord. In August, researchers announced they had caught the famous ‘Sailing Stones’ on camera, and have an answer to the decade-long riddle.
READ MORE // The Best of 2015 // #99: The First Snake
According to data from a weather station, images from a time-lapse camera, and GPS beacons on the rocks,
a perfect recipe of equal parts sun, rain, wind and ice sends the rocks across the desert.

Ice forms atop the dried bed of Death Valley, and in the morning the sun’s rays break apart that ice. Wind pushes these broken sheets of ice into the rocks. Ice begins to accumulate behind the boulders, providing the necessary pushing force to make the rocks ‘sail’.
There’s 99 more stories from 2014. Check out the Best of 2014 series here.
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