Racetrack Playa

Located in the northwestern side of Death Valley National Park, California is one of the most mysterious places called the Racetrack Playa. This is a scenic dry lake feature with “sailing stones” that leave linear “racetrack” imprints. The Racetrack Playa is 3608 feet above sea level, and 2.8 miles long by 1.3 miles wide. It is also exceptionally flat and level with the northern end being only 1.5 inches higher than the southern. The highest point surrounding it is 5,678 feet high Ubehebe Peak, rising 1970 feet above the lakebed 0.85 mile to the west.
 How Do They Move?
Some of these rocks weigh several hundred pounds so this makes the question about how they move a challenging one to explain! There has been several explanations about the way these rocks move.
One: Moved by people or animals?
The shape of the trails behind the rocks suggest that they move during times when the floor of Racetrack Playa is covered with a very soft mud. But with no disturbed mud around the tracks the rocks leave an animal or human pushing them seems impossible!

Two: Are they moved by wind?Probably one of the best explanations is wind. The wind in Racetrack Playa blows from southwest to northeast. Most of the rock trails are parallel to this direction. This is strong evidence that wind is the prime mover or at least involved with the motion of the rocks. 

Three: Moved by ice? Racetrack Playa at times is covered by a thin layer of ice. One idea is that water freezes around the rocks and then wind, blowing across the top of the ice, drags the ice sheet with its embedded rocks across the surface of the playa. 

NASA has even set people out there to find an explanation to this stunning mystery! How do you think these rocks are being moved?