Mother Nature does a lot of cool things, some of which continue to elude even modern science.
The GrindTv Blog reminds us that it's once again the time of year when big rocks, known as sailing stones, appear to move across the flat desert in Death Valley, California, without any help from humans or animals.
The mysterious moving rocks, which can weigh up to 700 pounds, leave behind trails that can extend for several hundred feet and may not necessarily move in a straight line.
No one is exactly sure what causes these rocks to scuttle across the 3-mile-long swath of sun-baked terrain known as Racetrack Playa. The phenomenon has not been observed anywhere else. But most scientists think that the rocks are pushed by strong winds after a rain storm.
The rocks tumble down onto the pancake-flat ground from surrounding mountains. A thin layer of ice or mud creates a slick surface that may help the rocks glide.
Of course, we can't be certain how this all works until someone sees the event in person. For now, we just have some very cool pictures to admire.
(Click the images to enlarge)
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