In Death Valley, 320-pound stones move on their own; we now understand how they accomplish this remarkable feat.

The Death Valley National Park in California is filled with unusual stones that move on their own, leaving long trails behind, as reported by IFLScience.

These so-called "sliding stones" can weigh up to 320 kg, but how can they traverse the landscape? This question has intrigued scientists since the 1940s, and only recently have researchers begun to unravel the mystery.

A team of scientists equipped some of the "sliding stones" with GPS trackers and captured their movement using time-lapse photography. This marked the first time these strange stones were caught "in the act." The findings of the study helped scientists understand what is really happening in Death Valley.

As is well known, the Racetrack Playa in Death Valley is quite dry and dusty during the summer months, but with the arrival of winter, a shallow seasonal pond appears on the playa. When temperatures drop, the water in the shallow pond starts to freeze, forming a very thin layer of ice that is only 3-6 millimeters thick. While this is a minimal amount of ice, it is sufficient for frozen slabs to be moved by the wind.

"A necessary condition for the movement of the stones that we observed is the existence of a pool on the playa that is deep enough to flood the southern part but shallow enough to leave many stones partially exposed on the surface of the pond. It is also important to have floating ice, temperatures, and sunlight that are adequate to create melt pools in the ice, along with light breezes that are steady enough to set the floating ice in motion," the authors of the study write.

According to data collected from the GPS trackers, the speed of the stones' movement was slow, at a rate of about 2-5 meters per minute.

During the study, scientists monitored the movement of 60 stones simultaneously, some of which traveled distances of up to 224 meters. It was suspected that ice might play a role in the phenomenon of moving stones, but it was a revelation to learn just how thin this ice needs to be and what gentle winds are required to set them in motion.

The movement of stones in Death Valley can take years or even decades due to insufficient precipitation and snow to create a sufficiently deep winter pond.

Let us recall that Hurricane Hilary brought an incredible amount of rainfall to Death Valley, turning once-dry ravines into raging torrents. As a result, the infamous Death Valley had to be closed to visitors for a full two months, marking "the longest closure in the park's history."