Posted on 07/15/2012 5:03:34 PM PDT by ForGod'sSake
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Central Mexico’s Lake Cuitzeo contains melted rock formations and nanodiamonds that suggest a comet impacted Earth around 12,900 years ago, scientists say. CREDIT: Israde et al. (2012)
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New evidence supports the idea that a huge space rock collided with our planet about 13,000 years ago and broke up in Earth's atmosphere, a new study suggests.
This impact would have been powerful enough to melt the ground, and could have killed off many large mammals and humans. It may even have set off a period of unusual cold called the Younger Dryas that began at that time, researchers say.
The idea that Earth experienced an asteroid or comet impact at the start of the Younger Dryas has been controversial, in part because there is no smoking-gun impact crater left behind as with other known events in our planet's past. But researchers say it's common for space rocks to disintegrate in the heat of a planet's atmosphere before they can reach the ground.
The scientists first reported their suspicions about the event in 2007. Now, they say, a new site in Central Mexico's Lake Cuitzeo displays telltale signs of an impact, including melted rock formations called spherules and microscopic diamonds that could only have formed under extreme temperatures.
The researchers, led by Isabel Israde-Alcántara of Mexico's Universidad Michoacana de San Nicólas de Hidalgo, published their findings online March 5 in the journal Proceedings of the National Academy of Sciences.
Buried evidence
"If you don't have a crater, you're a little bit lost," said space scientist Ted Bunch of Northern Arizona University, a member of the research team. "Here what we have is something similar to an aerial bomb blast. With these aerial bursts, with time all the evidence is wiped away unless it's buried." [Best Close Encounters of the Comet Kind]
In addition to the Mexican site, the scientists have found signs of an impact in Canada, the United States, Russia, Syria and various sites in Europe. And all of these bits of evidence were found buried in a thin layer of rock that dates to precisely 12,900 years ago.
"If you have an event like this in a 1- or 2-inch layer that dates to exactly the same age over a very large area, and you have high-temperature materials and nanodiamonds in there, the evidence pretty well points to an event that as pretty disastrous," Bunch told SPACE.com.
This wouldn't have been the only aerial impact event ever to hit Earth. Scientists think a space rock exploded over Siberia in 1908, flattening 500,000 acres (2,000 square kilometers) of forest in what's known as the Tunguska event.
Heat flash
If a comet, which would have been traveling at about 30 miles per second, impacted Earth's atmosphere, it would have created a flash of extreme heat reaching about 3,000 to 4,000 degrees Fahrenheit (1,600 to 2,200 degrees Celsius).
In addition to melting the ground, such temperatures would have proven cataclysmic to many kinds of life.
At the same time that the impact may have taken place — 12,900 years ago — Earth was beginning a mini ice age. It is known that many large animals, such as the mammoth and the saber-toothed cat, did not survive this age. There's even evidence of a population decline in humans living in North America at the time, called the Clovis culture.
The researchers aren't claiming that the comet impact caused the climate changes at the time, but Bunch said such an event would have had a significant effect on Earth's climate.
"We're not going to come out and say it did do it, but it's more than a coincidence that the timing happened exactly the time that a lot of climatic conditions occurred and you had the loss of various species," Bunch said.
Still, the researchers predict some skeptics will remain unconvinced that Earth was hit by space rock during the Younger Dryas.
"There's always going to be theoretical and statistical people who would never believe it even if they were there," Bunch said."I think what we're trying to do is open up a vista there for people to examine the data themselves and make their own conclusions."
From a VERY long COMPANION ARTICLE it seems the group which includes Firestone, Kennett et al have settled on ~12,900 years ago. No mention of their dating method that I could find.
Now Berringer is a whole 'nother story. I haven't read anything anywhere(haven't really looked) about their dating method. Many moons ago???
Well done but eeewwww!!! I think null and void may be a guy.
Hung a few tags on it...
http://www.amazon.com/Defense-Virginia-South-R-Dabney/dp/0873779290
“A Defense of Virginia and the South”
SHEESH; I’m getting a headache!!! How’s about the Cliffs Notes version?
It is interesting that more and more evidence is piling up to support the hypothesis in Firestone et al.’s book. The article talks of the ice age ending at the time of the Younger Dryas which was then made worse. My understanding is the the ice age was ending around 15 to 18,000 years ago, and that this event/series of events triggered the Younger Dryas. Firestone’s book documents very widespread effects from Canada to our Southwest and even northwestern Europe. My vote would be for more than one impactor. After all, remember how many boloids struck Jupiter a few years ago.
The Carolina Bays are one such phenomenon possibly caused. My guess is that huge blocs of ice were thrown out, skidded to a stop and melted. Lake Michigan appears to have been formed by 2 or 3 impactors whose traces are found underwater. The Clovis culture was decimated as were large numbers of the great mammals.
The Tungusku event was small by comparison. A similar event occurred in the Brazilian jungle several decades later but was somewhat smaller in size. We are only beginning to appreciate the impact of boloid events on our earth and our history. Sunken Civ has brought to our attention the discover of a 2 mile crater in the drained Iraq Marshes whih fell about 4,000 years ago. Was this the cause of the First Intermediate Period in Egypt about that time? Ipuwer records a time of terrible social upheaval and distress in a papyrus. There are also fairly large meteor craters found in Argentina around the same period or perhaps a little earlier. So much to learn, so little time!! But first we have to use our open minds.
Again with the anti-Bible stuff.
Slavery, as mentioned/defined/used in the Bible is NOT the slavery we encountered here. It was more ‘indentured servant’ style. In no place does the Bible ‘endorse’ the practice of slavery, as we know it to be.
Context, especially historical, is everything.
I read several essays by Robert Schoch last night who, for whatever reasons I give some elevated credence to. Most everything I've read of his APPEARS an honest assessment, circumventing most of the PCBS, but that's just me. Anyhow, early on he leaned towards impactor(s) but he now leans more towards plasma discharges, from whatever source(s), primarily our sun. He tiptoed around Velikovsky's premise of a close flyby of say, Venus, by alluding to OTHER possible charged bodies. BTW, he doesn't eliminate impactors altogether and confesses there may have been more than one contributing factor. FWIW...
Really? Do you know nobody personally that believes this? I sure as a literal hell don’t.
You’re responding to a 9 year old post?
May I Lobby you to find a better Hobby?
Oh wait, they’re closed on Sunday, nvrmnd.
And in case you missed it,
“I find it every bit as true as most Christians use the Bible to justify slavery.”
Since most, nearly all, Christians do NOT use the Bible to justify slavery, I find it untrue.
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