A rock on the Racetrack Playa with a sandy trail falling away behind it.

Mystery solved? Again?

In tonight’s video, Juice Rap News return with a look at the latest headlines (previously on the Watercooler).

A Rap News summary of the past months’ remarkable series of events. From Gaza to Syria, ISIS to Ukraine, Sinkholes to Ebola, Ferguson to Robin Williams, the world has been experiencing a seemingly endless series of events befitting of a Ronald Emmerich movie. How do we manage to deal with all the painful ironies and bloody tragedies of these times? To find out, we tune into frequency which informs us about all these events: the mainstream media. Join veteran MSMBS host Brian Washington as he brings you all the latest World News Headlies — without a trace of irony.

Written & created by Giordano Nanni & Hugo Farrant in a suburban backyard home studio in Melbourne, Australia, on Wurundjeri Land.

Also in a previous watercooler, we discussed Death Valley’s Racetrack Playa, where stones mysteriously move across the surface of the desert. NASA scientists proposed that thick sheets of ice were involved, but now researchers have gained insight from actually watching the rocks move! From the Scripps Institute at UC San Diego:

Because the stones can sit for a decade or more without moving, the researchers did not originally expect to see motion in person. Instead, they decided to monitor the rocks remotely by installing a high-resolution weather station capable of measuring gusts to one-second intervals and fitting 15 rocks with custom-built, motion-activated GPS units. (The National Park Service would not let them use native rocks, so they brought in similar rocks from an outside source.) The experiment was set up in winter 2011 with permission of the Park Service. Then – in what Ralph Lorenz of the Applied Physics Laboratory at the Johns Hopkins University, one of the paper’s authors, suspected would be ‘the most boring experiment ever’ – they waited for something to happen.

But in December 2013, Norris and co-author and cousin Jim Norris arrived in Death Valley to discover that the playa was covered with a pond of water seven centimeters (three inches) deep. Shortly after, the rocks began moving.

‘Science sometimes has an element of luck,’ Richard Norris said. ‘We expected to wait five or ten years without anything moving, but only two years into the project, we just happened to be there at the right time to see it happen in person.’

Their observations show that moving the rocks requires a rare combination of events. First, the playa fills with water, which must be deep enough to form floating ice during cold winter nights but shallow enough to expose the rocks. As nighttime temperatures plummet, the pond freezes to form thin sheets of ‘windowpane’ ice, which must be thin enough to move freely but thick enough to maintain strength. On sunny days, the ice begins to melt and break up into large floating panels, which light winds drive across the playa, pushing rocks in front of them and leaving trails in the soft mud below the surface.

[...] These observations upended previous theories that had proposed hurricane-force winds, dust devils, slick algal films, or thick sheets of ice as likely contributors to rock motion. Instead, rocks moved under light winds of about 3-5 meters per second (10 miles per hour) and were driven by ice less than 3-5 millimeters (0.25 inches) thick, a measure too thin to grip large rocks and lift them off the playa, which several papers had proposed as a mechanism to reduce friction. Further, the rocks moved only a few inches per second (2-6 meters per minute), a speed that is almost imperceptible at a distance and without stationary reference points.

[...] Individual rocks remained in motion for anywhere from a few seconds to 16 minutes. In one event, the researchers observed rocks three football fields apart began moving simultaneously and traveled over 60 meters (200 feet) before stopping. Rocks often moved multiple times before reaching their final resting place. The researchers also observed rock-less trails formed by grounding ice panels – features that the Park Service had previously suspected were the result of tourists stealing rocks.

So maybe no one is stealing racing rocks after all!

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