Prehistoric meteor shower? |
Prehistoric meteor shower? |
Dec 13 2007, 07:02 PM
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Member Group: Members Posts: 688 Joined: 20-April 05 From: Sweden Member No.: 273 |
A real weird news story from Nature about meteor damage to pleistocene fossils:
http://www.nature.com/news/2007/071212/ful...s.2007.372.html If traces of this meteor shower has been found in both Siberia and Alaska as the story implies, then multiple impactors must have been involved. Such small meterites would lose speed quickly so the airburst must have occurred at fairly low altitude. |
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Dec 17 2007, 09:35 PM
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Huh. That's pretty damn scary, really. What could cause a metallic body to apparently, literally explode to the degree needed to generate small high-speed fragments like this? All I can think of is a VERY high impact velocity that basically melts the thing in a few milliseconds, but that sounds screwy to me, too...
My previous Tunguska-style scenario doesn't sound plausible, either. I don't see why any chunks of iron-nickel wouldn't survive the explosion of the volatiles more or less intact instead of shattered into shrapnel. There's a big piece of this puzzle missing. A lot's going to depend on the actual age of the fossils. If it's later then the colonization of North America, then I'd definitely favor the spearhead theory (IIRC, 30Kyears is still just barely within the realm of possibility for human migration to the Americas). -------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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