On a cracked lakebed in Death Valley called Racetrack Playa, there are a collection of stones, some weighing several hundred pounds, that clearly, mysteriously, move. They leave long serpentine trails behind them in the dirt, and for decades visitors have guessed at how they migrate across the desert floor. Hurricane force winds, sliding sheets of ice — and, of course, aliens — were all contenders, but then last December the cousins Richard Norris and James Norris caught the rocks in the act.
In a paper published in Plos One, they describe watching a thin layer of ice break into large panes and get pushed by a light wind against the boulders, which then began to slide through the mud at about 15 feet a minute. "We were sitting on a mountainside and admiring the view when a light wind kicked up and the ice started cracking," Richard told the LA Times. "Suddenly, the whole process unfolded before our eyes."
Sailing stones, courtesy of Plos One
Geologists have been studying the...
Finally caught on camera