Mystery of moving boulders in Death Valley solved
An unlikely answer may explain how large boulders move across the desert all by themselves.
That’s what the slithering stones in Death Valley, Calif., do.
These boulders leave trails as they move, but no one understood how.
But some scientists set up GPS trackers and cameras to find the answer.
They say the movement is caused by ice, even though this is usually one of the hottest places on earth.
But in the winter, there are lake beds that can freeze.
The scientists say that when the sun rises, thin sheets of ice slide atop the melted water and push the rocks.