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n2doc

(47,953 posts)
Mon May 28, 2012, 05:07 PM May 2012

The Enigma 1,800 Miles Below Us

As if the inside story of our planet weren’t already the ultimate potboiler, a host of new findings has just turned the heat up past Stygian.

Geologists have long known that Earth’s core, some 1,800 miles beneath our feet, is a dense, chemically doped ball of iron roughly the size of Mars and every bit as alien. It’s a place where pressures bear down with the weight of 3.5 million atmospheres, like 3.5 million skies falling at once on your head, and where temperatures reach 10,000 degrees Fahrenheit — as hot as the surface of the Sun. It’s a place where the term “ironclad agreement” has no meaning, since iron can’t even agree with itself on what form to take. It’s a fluid, it’s a solid, it’s twisting and spiraling like liquid confetti.

Researchers have also known that Earth’s inner Martian makes its outer portions look and feel like home. The core’s heat helps animate the giant jigsaw puzzle of tectonic plates floating far above it, to build up mountains and gouge out seabeds. At the same time, the jostling of core iron generates Earth’ magnetic field, which blocks dangerous cosmic radiation, guides terrestrial wanderers and brightens northern skies with scarves of auroral lights.

Now it turns out that existing models of the core, for all their drama, may not be dramatic enough. Reporting recently in the journal Nature, Dario Alfè of University College London and his colleagues presented evidence that iron in the outer layers of the core is frittering away heat through the wasteful process called conduction at two to three times the rate of previous estimates.

more

http://www.nytimes.com/2012/05/29/science/earths-core-the-enigma-1800-miles-below-us.html

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The Enigma 1,800 Miles Below Us (Original Post) n2doc May 2012 OP
What a great find. A lot to consider. truedelphi May 2012 #1
Fascinating stuff. Thanks for posting, n2doc... Surya Gayatri May 2012 #2
interesting read... madrchsod May 2012 #3
Great find! Thanks for posting. A favorite tidbit... Scuba May 2012 #4

truedelphi

(32,324 posts)
1. What a great find. A lot to consider.
Mon May 28, 2012, 05:15 PM
May 2012

Thank you for posting about this. Something to ponder once M Day guests have all left.

 

Scuba

(53,475 posts)
4. Great find! Thanks for posting. A favorite tidbit...
Mon May 28, 2012, 07:28 PM
May 2012
The core accounts for only one-sixth of the volume of the Earth but one-third of its mass, the great bulk of iron maintained in liquid form by the core’s hellish heat. “Liquid” in this case doesn’t mean molten like lava. “If you could put on your safety gloves and stick your hands into the outer core, it would run through your fingers like water,” said Bruce Buffett, a geologist at the University of California, Berkeley.




So basically the planet is like a series of nested balls, with in at least one case, a lubricant to allow them to move independently, as suggested in the article. The whole thing's fascinating.
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