Death Valley is the hottest place on the planet, the driest place in North America, and, in the northwestern region of Caliifonia's Death Valley National Park, home to the eerie and at times haunted-seeming playa -- dried lakebed -- known as the Racetrack. Here, periodic rain forms a skin of cracked, dried mud on the parched earth. This is the part of Death Valley where things move on their own. And not just little things. Massive things. Rocks that weigh hundreds and hundreds of pounds.
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You might have heard of Death Valley’s famous sailing stones -- stones that slide across the surface of the Racetrack with nothing appearing to push or pull them, leaving sharp, eerie tracks in the mud behind them. But you haven’t seen them move -- no one has, not in person, though in 2014 the rocks were finally caught in motion via remote time-lapse photography.
You might have naturally assumed that these stones were small. In fact some weigh upwards of 500 pounds. You might presume they moved a few feet, maybe a few dozen feet, but scientists have found trails that measure well over 1,000 feet, leaving zig-zagging along the cracked landscape like erratic drivers. Perhaps the thing you were most likely to assume about these stones is that -- especially since no one sees them do it -- they move imperceptibly, maybe a few inches a day max. They can move more than 15 feet in a single minute.