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Ending a half-century of geological speculation, scientists have finally seen the process that causes rocks to move atop Racetrack Playa, a desert lake bed in the mountains above Death Valley, California. Researchers watched a pond freeze atop the playa, then break apart into sheets of ice that — blown by wind — shoved rocks across the lake bed. Until now, no one has been able to explain why hundreds of rocks scoot unseen across the playa surface, creating trails behind them like children dragging sticks through the mud. “It’s a delight to be involved in sorting out this kind of...

The first witnesses to an enduring natural mystery are an engineer, a biologist and a planetary scientist who met thanks to a remote weather station. Lacking direct evidence, explanations for this geologic puzzle ran the gamut, from Earth's magnetic field to gale-force winds to slippery algae. Now, with video, time-lapse photographs and GPS tracking of Racetrack Playa's moving rocks, the mystery has finally been 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. Now two researchers at the Scripps Institution of Oceanography at the University of California, San Diego, have photographed these "sailing rocks" being blown by light winds across the former lake bed. Richard Norris and James Norris said the movement is made possible when ice sheets that form after rare overnight rains melt in the rising sun, making the hard ground muddy and slick. On Dec. 20, 2013, the...

It's a geological enigma that's had scientists speculating for half a century. But the mystery behind Death Valley's 'Wandering Stones' has finally been uncovered. It was previously unknown what caused the rocks to move across Racetrack Playa, a desert lake bed in the mountains above California's Death Valley, leaving their distinctive trails behind them. But researchers have witnessed a thin layer of water freezing over the lake, before breaking into sheets the thickness of a window pane and nudging the rocks as they were blown by the breeze. “It’s a delight to be involved in sorting out this kind of...

(Image: NASA/JPL-Caltech/University of Arizona) A rolling stone gathers no moss – but on Mars it can nevertheless cloak itself in mystery. This NASA image shows the track of a boulder that rolled across the Nili Fossae region of Mars. For now it is anyone's guess what set the rock in motion. This false-colour picture (click on it for higher resolution) was posted on 7 June to the Beautiful Mars Tumblr feed, a collection of high-resolution shots from the HiRISE camera aboard NASA's Mars Reconnaissance Orbiter. It shows dark, jagged tracks left in the soil by a lumpy boulder, probably...

One of the mysterious peripatetic, or roving, rocks of Death Valley National Park in California and Nevada sits at the end of a curved track in a summer 2010 picture. Found in the Racetrack—an aptly named dry lakebed, or playa—the moving rocks have stumped scientists since the 1940s. For instance, the rocks are thought to move as fast as a walking person, but they've never been seen in action. Previous studies have shown that gravity or earthquakes can't explain the objects' movements. Now a student-research project led by NASA's Goddard Space Flight Center has lent support to the idea that,...

Actively studied for 50 years, the rocks that mysteriously move around the dried lake bed playa in Death Valley, called the Racetrack, are yet to have an unquestionable explanation for their movement. ... In 1976 Robert Sharp and Dwight Carey diputed the ice-sheet theory. They analyzed the tracks and concluded because of track characteristics and the geometries of the tracks relative to each other that ice sheets could not have been involved in forming the tracks and moving the rocks. Sharp and Carey concluded due to the non-parallel nature and the crossing of some trails that it would be impossible...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 April 10 Unusual Rocks in Death Valley Credit & Copyright: Joe Orman Explanation: How did those big rocks end up on that strange terrain? One of the more unusual places here on Earth occurs inside Death Valley, California, USA. There a dried lakebed named Racetrack Playa exists that is almost perfectly flat, with the odd exception of some very large stones, one of which is pictured above....

By now, most of us know there is water on the moon. But did you know that it comes in three flavors and there is so much of it--158 billion gallons--that it could fill all of Seattle's water needs for three years? It turns out there is water all over the lunar landscape, which is rather astonishing since astronomers were convinced for such a long time that it was bone dry. Discovery.com and Space.com report this all changed when actual measurements were taken using the Mini-SAR and Moon Mineralogy Mapper (M3 or "M-cubed") instruments on India's Chandrayaan-1 moon probe and...

Boulder, CO, USA – A geologist's sharp eyes and upset stomach has led to the discovery, and almost too-close encounter, with an otherworldly geological process operating in a remote corner of northern Chile's Atacama Desert. The sour stomach belonged to University of Arizona geologist Jay Quade. It forced him and his colleagues Peter Reiners and Kendra Murray to stop their truck at a lifeless expanse of boulders which they had passed before without noticing anything unusual. "I had just crawled underneath the truck to get out of the sun," Quade said. The others had hiked off to look around, as...