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How Do Death Valley’s “Sailing Stones” Move Themselves Across the Desert?


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Thought this was fascinating and had to share it.

Click image for a larger view.

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The full story is here ~ http://www.smithsonianmag.com/travel/How-Do-Death-Valleys-Sailing-Stones-Move-Themselves-Across-the-Desert-210843681.html?utm_medium=email&utm_source=smithsoniansciandnat&utm_campaign=201306-science

Eventually, Lorenz employed a tried-and-true method for testing his nascent idea: the kitchen-table experiment. “I took a small rock, and put it in a piece of Tupperware, and filled it with water so there was an inch of water with a bit of the rock sticking out,” he says. “I put it in the freezer, and that then gave me a slab of ice with a rock sticking out of it.” He flipped the rock-ice hybrid upside down and floated it in a tray of water with sand on the bottom. By merely blowing gently on the ice, he realized, he could send the embedded rock gliding across the tray, scraping a trail in the sand as it moved. After decades of theoretical calculations by countless scientists, the answer seemed to be sitting on his tabletop.
Lorenz and his team presented their new model in a 2011 paper. “Basically, a slab of ice forms around a rock, and the liquid level changes so that the rock gets floated out of the mud,” he explains. “It’s a small floating ice sheet which happens to have a keel facing down that can dig a trail in the soft mud.” Calculations show that, in this scenario, the ice causes virtually no friction on the water, so the stones are able to glide with just a slight breeze. The team argues that their model accounts for the movement far better than any other, since it doesn’t require massive wind speeds or enormous ice sheets.

DarleneSignaturePic1.jpg

"Time is too slow for those who wait; too swift for those who fear;

too long for  those who grieve; too short for those who rejoice.

But for those who love, time is eternity."

(Jane Fellowes)

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BEER---> Been to 'Death Valley' (never in the Summer), that story might be true in other places. But not in Death Valley. There is another reason for this to happen in Death Valley. Don't know how to work the spoiler thingy. Sooo, I'll give out the answer if you want - later.

BELCH

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Beer---> Spoilers work the same way as images and quotes. With spaces in-between.... at the beginning... [ spoiler ] at end... [ / spoiler ]. Hopefully the spaces will keep it from spoiling...LOL

NUT

DarleneSignaturePic1.jpg

"Time is too slow for those who wait; too swift for those who fear;

too long for  those who grieve; too short for those who rejoice.

But for those who love, time is eternity."

(Jane Fellowes)

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BEER----> Reminds me of a Bob Dylan song also sung by Peter, Paul and Mary......."Blowing in the Wind."

NUT

DarleneSignaturePic1.jpg

"Time is too slow for those who wait; too swift for those who fear;

too long for  those who grieve; too short for those who rejoice.

But for those who love, time is eternity."

(Jane Fellowes)

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Go Dylan ! ! !

Hey BEER----> I do believe you've lost your BELCH----> it's BELCG now. I can't even pronounce it.

NUT

Searched "Things that blow in the wind" and found these comical images. LOL

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post-3933-0-01597200-1373478738_thumb.jp

post-3933-0-46444500-1373478745_thumb.jp

DarleneSignaturePic1.jpg

"Time is too slow for those who wait; too swift for those who fear;

too long for  those who grieve; too short for those who rejoice.

But for those who love, time is eternity."

(Jane Fellowes)

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  • Elders (Admins)

I had read about that ice hypothesis before, but hadn't heard of that experiment. It does sound very possible. I guess it's a bit like just a thin film of oil can make a floor slippery.

Beer, I think even Death Valley gets frost at times. Also, if the grains of sand are very round, that'd reduce the friction. A bit like treading on a load of ball bearings.

I love how nature does the "impossible".

Libby

"Humans need fantasy to be human. To be the place where the falling angel meets the rising ape." Terry Pratchett

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Speaking of the impossible, click on this image for a closer look.......

post-3933-0-61612300-1373643714_thumb.jp

DarleneSignaturePic1.jpg

"Time is too slow for those who wait; too swift for those who fear;

too long for  those who grieve; too short for those who rejoice.

But for those who love, time is eternity."

(Jane Fellowes)

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