According to a Death Valley National Park representative who was apparently unable to share their full name or title with us, which is very mysterious and thus on brand , the stones are difficult to catch in action because they only move under special conditions. After a storm, thin but extremely slippery ice can form on the playa, allowing strong winds to push even bison-sized rocks across the surface and leave tracks in the mud behind them.
And considering Death Valley is infamously dry, that means opportunities to catch the stones in action are scarce. Your best bet may be to head out between December-February and check the forecast for rain. But the likelihood of seeing the stones go gliding all across creation is pretty low. Still, the trails they create in the earth are a pretty wild sight. The southeastern segment of the Racetrack generally makes for the best views.
During your visit, remember that this is a fragile place: avoid leaving tracks, offroading, or moving the stones they can do it themselves, dammit! Other researchers believed the strong winds that frequently whip across the vast lake bed could cause the rocks to slide across the ground. These and other theories were eventually disproved, leaving scientists without an explanation. In some cases the rocks' trails were measured to be as long as feet meters , according to Slate.
Some of the trails formed a graceful curve, while other trails created a straight line, then an abrupt shift to the left or right, which further baffled researchers. Lorenz was particularly keen on comparing the meteorological conditions of Death Valley to those near Ontario Lacus , a vast hydrocarbon lake on Titan, a moon of Saturn.
But while investigating Death Valley, he became intrigued by the enigmatic sailing stones of Racetrack Playa. Lorenz developed a kitchen-table model — using an ordinary Tupperware container — to show how the rocks might glide across the surface of the lake bed.
He had little faith that the GPS-equipped rocks would move in a time frame that anyone would capture.
But when the researchers travelled to the playa in December to check instruments and change batteries, they found a huge ice-encrusted pond covering about one-third of the 4.
After several days of camping, they decided to sit above the southern end of the playa on the morning of 20 December. They watched as the ice began moving past the rocks, mostly breaking apart but also shoving them gently. The rocks began to inch along, but their pace was too slow to spot by eye.
But when the ice melted away that afternoon, they saw freshly formed trails left behind by more than 60 moving rocks. And on 9 January, James Norris returned to the playa with Lorenz and was able to record video of the roving rocks.
And the two events the scientists saw, with thin ice panes shoving the stones across a wet playa, do not necessarily explain every instance of rocks moving there. Solving the Racetrack Playa mystery is not exactly a major scientific breakthrough, Lorenz says, but the work does show the rare combination of conditions that allow rocks to move seemingly on their own.
And ice shove can have notable effects — in , it uprooted enough telephone poles at a lake in Nevada to break a transcontinental telephone line. One person who is happy to see the latest results is Dwight Carey. As a university student in the s, he helped with an experiment in which two rocks were placed in a corral on the playa.
Over the course of a winter, one stone moved out of the corral, unobserved, and the other did not 2. Norris, R. Sharp, R. Download references.
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