Death Valley’s mystery solved

For years scientists have theorized about how large rocks some weighing hundreds of pounds zigzag across Racetrack Playa in Death Valley National Park, leaving long trails etched in the earth.It’s called Racetrack Playa — and for decades geologists have been chasing the “sailing stones” at play there. One of the first scientific studies, published in 1948, suggested the rock motion was driven by dust devils.