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Politics : Evolution -- Ignore unavailable to you. Want to Upgrade?


To: 2MAR$ who wrote (40763)8/30/2013 11:55:07 AM
From: average joe1 Recommendation

Recommended By
Solon

  Read Replies (1) | Respond to of 69300
 
“There is a cult? of ignorance in the United States, and there has always been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that "my ignorance is just as good as your knowledge."” Isaac Asimov



To: 2MAR$ who wrote (40763)8/30/2013 2:17:53 PM
From: Solon  Respond to of 69300
 
Exactly! And the most subjective morality always belongs to those who get their morality from the imagination--where no objective refutation is remotely possible. Religious morality is always self serving and always divisive. And there can never be peace on earth as long as these boastful, self serving, Pretenders to special status, continue to engage one another on the battlefields of superstition and ignorance.



To: 2MAR$ who wrote (40763)8/30/2013 5:02:47 PM
From: Solon1 Recommendation

Recommended By
average joe

  Respond to of 69300
 
"But Coggon's rock samples suggest that Earth's mantle had already been topped up with iron-loving minerals by 4.1 billion years ago, meaning the Late Veneer, and the birth of Earth's oceans, must have occurred earlier. It may actually have been before 4.3 billion years ago, says Coggon: rocks of that age discovered last year hint that, at the time they formed, Earth's mantle was already rich in iron-loving minerals ( Nature Geoscience, doi.org/njz)."

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"EARTH may have become the blue planet just 200 million years after it formed, making it a welcoming home for life hundreds of millions of years earlier than we thought.

Earth's first 600 million years are called the Hadean – for good reason. "It is traditionally seen as a period of Earth history when our hot, young planet was hellish and uninhabitable," says Judith Coggon at the University of Bonn, Germany.

But hell may actually have been relatively short-lived. Coggon and her colleagues have found that rocks in Greenland contain a chemical signature from the mantle 4.1 billion years ago – just 400 million years after our planet was born. That signal suggests conditions at the time may have been more like they are today than we expected.

Models suggest some "iron-loving" metals like gold and platinum – which dissolve in molten iron – should all have sunk into the iron-rich core as it formed. Because they are relatively abundant in the mantle today, it has been suggested that meteorites and comets smashing into Earth about 3.9 billion years ago replenished the stock. This hypothesised event, known as the Late Veneer, is also thought to have given Earth most of its water, delivered as ice.

But Coggon's rock samples suggest that Earth's mantle had already been topped up with iron-loving minerals by 4.1 billion years ago, meaning the Late Veneer, and the birth of Earth's oceans, must have occurred earlier. It may actually have been before 4.3 billion years ago, says Coggon: rocks of that age discovered last year hint that, at the time they formed, Earth's mantle was already rich in iron-loving minerals ( Nature Geoscience, doi.org/njz).

If so, Earth gained its oceans little more than 200 million years after it formed – which also pushes back the date for the earliest possible origin of life, says Coggon."