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Asteroid 'destroyed life 250m years ago'Earth's biggest mass extinction 251 million years ago was triggered by a collision with a comet or asteroid, US scientists say. They have reached this conclusion by looking at atoms from a star trapped inside molecular cages of carbon...
by Dr David Whitehouse
Friday, February 23, 2001
In rock layers laid down at the time, there is a much higher concentration of complex carbon molecules called fullerenes that have different types, or isotopes, of helium and argon trapped inside them. These molecules could only have been delivered from space, the researchers say...
The researchers believe these particular fullerenes are extraterrestrial because the gases trapped inside have an unusual ratio of isotopes that indicate they were made in the atmosphere of a star that exploded before our Sun was born...
The telltale fullerenes were extracted from sites in Japan, China and Hungary, where the sedimentary layer at the boundary between the Permian and Triassic periods had been exposed...
The research was made difficult because there are few 251-million-year-old rocks left on Earth. Most rocks of that age have been recycled through the planet's tectonic processes...
Researchers estimate the comet or asteroid was six to 12 km (3.7 - 7.4 miles) across, or about the size of the asteroid believed responsible for the extinction of the dinosaurs 67 million years ago...
The mass extinction of 251 million years ago was the greatest on record.
There's also an impact crater buried under eastern Antarctica. The crater is about the size of the state of Ohio, and the asteroid that caused it was probably 30 miles wide. That event also dates from the P/T boundary. Either of them would have been hefty enough to cause worldwide climatic instability lasting for milennia, not to mention the initial cascade of firestorms resulting from ejecta falling bath onto Earth. And the locations of both creaters might have been sufficent to give the opposite side of the world (Siberia at that time) a hefty boot from below. Any putative Siberian magma chambers existing then could conceivable have moved closer to the surface and/or actually broken out, yielding the Siberian Traps as we know them.
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Scientists are constantly ruling out God in their theories. The climate change that froze Antarctica, and the fossils found there, were caused by the world-wide flood of Noah’s day. The earth’s temperature before then was virtually uniform due to “the expanse” above the earth that acted as an insulator.
Creatively mixing science with mythology is the essence of the “New Scientist”.
The discovery may have implications for how modern animals will adapt to global warming.
This is clearly Bush's fault. He went back in time and brought with him a large fleet of SUVs to pollute the atmosphere.
There are a few theories why the extinction happened. I go with the huge volcanic flows in Siberia.(Graphic shows how continents have moved over the last 250 million years)
New Fossils Suggest Ancient Cat-sized Reptiles in Antarctica
LiveScience.com on Yahoo | 6/7/08 | Jeanna Bryner
Posted on 06/07/2008 7:53:24 PM PDT by NormsRevenge
http://www.freerepublic.com/focus/news/2027763/posts