Ancient Asteroid Impact Coated Earth in Blanket of Beads

The asteroid linked to dinosaurs' demise 65 million years ago slammed into the Yucatan Peninsula with such force it pulverized Earth's crust. The result was a veil of airborne carbon beads that blanketed the planet, a new study finds.

Spanning about 124 miles (200 kilometers), the giant indentation left by the asteroid impact continues to be a treasure trove of clues for scientists piecing together the wipe-out of 70 percent of life on Earth, including non-avian dinosaurs. Called the Chicxulub Crater, this CSI-site is located just west of Mexico's Yucatan Peninsula.

Geologists generally agree an asteroid slammed into Earth at the end of the Cretaceous period; that the catastrophic impact sent molten rock and super-hot ash airborne; and that as the molten material fell from the sky, it ignited flammable flora, sparking forest fires.

More perplexing has been the formation of carbon particles called cenospheres hiding out in rocks of the Chicxulub Crater and other sites. One idea was that the carbon beads were charred remnants formed as a result of the plant-burning.

That seemed plausible since, until now, such carbon beads were associated only with modern power plants, and scientists thought intense burning of coal and crude oil generated the structures. Power plants didn't exist 65 million years ago, and even heat produced by pressure from layers of earth deposited atop the dino fossils would not have been sufficient to form the beads.

However, flames were not needed, say the current researchers, who find besides that the combustion of plants wouldn't produce such paleo-beads. Rather than a flammable origin, the carbon beads could have formed from the violent pulverization of the Earth's carbon-rich crust.

Their counter-view, detailed in this month's issue of the journal Geology, comes from analyses of cenospheres within rock samples collected at oceanic and inland locations around the world.

"Carbon embedded in the rocks was vaporized by the impact, eventually forming new carbon structures in the atmosphere," said researcher Simon Brassell, a geologist at Indiana University, Bloomington.

The study was funded by the Geological Society of America, Indiana University, and the Society for Organic Petrology.

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Sahara made slow transition from green to desert: study

A picture taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASAs Terra satelliteon shows dust blowing northward out of the Sahara Desert and over the Mediterranean Sea. The Sahara became the world's biggest hot desert some 2,700 years ago after a very slow fade from green, according to a new study which clashes with the theory that desertification came abruptly.

The Sahara became the world's biggest hot desert some 2,700 years ago after a very slow fade from green, according to a new study which clashes with the theory that desertification came abruptly.
Six thousand years ago, the massive arid region dominating northern Africa was quite green, a patchwork of trees and savannas as well as many sparkling lakes.

The region, larger than Australia, also was inhabited, according to the European-US-Canadian team of scientists behind a study in Science dated May 9.

Most of the physical elements that could tell the tale of the Sahara's geographic evolution have been lost. The scientists studied layers of sediment in one of the largest remaining Sahara lakes, Yoa, in a remote spot in northern Chad, which took them back through six millennia of climate history.

They looked at sediments, did soil tests and reviewed biological indicators such as plant and tree pollen and spores that were present before the desert encroached. They also studied the remains of aquatic microorganisms.
Their findings contradicted previous modeling that indicated a rapid collapse of vegetation in the region in a sudden end to the African Humid Period, about 5,500 years ago, said Stefan Kropelin, a geologist at the Prehistoric Archaeology Institute of the University of Cologne who took part in the new study.

In 2000, a study by Peter de Menocal of Columbia University of sediments in the west of Mauritania found a sudden increase in wind-carried dust blown off the Sahara region, suggesting swift climate change.

But data from Lake Yoa shows the opposite, and the transition to desert took its time, said Kropelin. He said he believed de Menocal's data were not wrong but misinterpreted.
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SOLAR ENERGY AS CHEAP AS COAL!

Energy company Sunrgi recently announced an astounding new solar system that will break our grids free from the fossil fuel lockdown. Their Xtreme Concentrated Photovoltaics promise a low-cost, high-efficiency system with an incredible projected energy pricing of 5 cents per kilowatt. This breakthrough puts solar on par with the cost of coal, natural gas, and other non-renewable energy sources.

If solar energy is ever going to live up to it’s world-changing potential, it’s going to have to mesh with our existing energy infrastructure, competing with coal and natural gas on price point. While traditional photovoltaic arrays span great expanses and struggle to keep costs down, Sunrgi’s system proposes a novel idea, making better use of fewer expensive materials.

The XCPV system is based on a principle blinding in its simplicity: use a magnifying glass to concentrate the sun’s energy into a single high efficiency solar cell. Each unit features a lens that magnifies the sun’s rays 2,000 times, focusing it onto a solar cell that converts more than 37% sunlight to energy. The result is a system that maximizes the potential output of each solar cell while minimizing cost and space required.

The units are modular and thus easily deployable on or off-grid, and they can be easily upgraded to accommodate future advancements in solar cell technology. To deal with the tremendous temperature of focused sunlight (more than 3,000 ºF!), Sunrgi has developed a proprietary cooling system that keeps the panels safe and sound. Rounding out the tech is a sun-tracking system and a PV cell composition that doesn’t depend on the world’s depleted silicon reserves.

Craig Goodman, president of the National Energy marketers Association, has stated that “Solar power at 5 cents per kWh would be a world-changing breakthrough. It would make solar generation of electricity as affordable as generation from coal, natural gas, or other non-renewable sources, without require and subsidy.”

Sunrgi has built and tested working prototypes, and has announced plans for commercial production in 12-15 months.

+ Sunrgi

Via nextenergynews.com

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