Comet (or gamma ray burst) killed N. Americans 13,000 y/a?

[docm]

A two parter; evidence of a catastrophic impact event in paloeindian N. America at nearly the same time as a possible supernova or GRB event documented in 2001 by researchers at Lawrence Berkeley. IMO this gets very weird....and just a bit too coincidental <img src="/images/icons/tongue.gif" /><br /><br />Link....<br /><br /><b>Did a comet wipe out prehistoric Americans?</b><br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>The Clovis people of North America, flourishing some 13,000 years ago, had a mastery of stone weaponry that stood them in good stead against the constant threat of large carnivores, such as American lions and giant short-faced bears. It's unlikely, however, that they thought death would come from the sky.<br /><br />According to results presented by a team of 25 researchers this week at the American Geophysical Union meeting in Acapulco, Mexico, that's where the Clovis people's doom came from. Citing several lines of evidence, the team suggests that a wayward comet hurtled into Earth's atmosphere around 12,900 years ago, fractured into pieces and exploded in giant fireballs. Debris seems to have settled as far afield as Europe.<br /> /><br /><font color="yellow"><b>Exactly where the explosion might have occurred is uncertain, but several clues point to the north of the continent. Levels of the apparent extraterrestrial debris, for example, are highest at the Gainey archaeological site in Michigan, just beyond the southern reach of North America's primary ice sheet 12,900 years ago. Moreover, levels decrease the further you go from Gainey, suggesting that the comet blew up largely over Canada – perhaps over Ontario or the Hudson Bay region.</b></font>/b><br /><br />However, this cosmic wallop does not seem to have left behind any obvious crater. In all probability, says Arizona-based geophysicist and team membe</p></blockquote> <div class="Discussion_UserSignature"> </div>

 

[derekmcd]

Sounds reasonable to me. I only read your excerpts and geology is not my forte, but even with no crater, a large enough comet can and will still add an enormous amount of energy wether it hits in intact as one piece or breaks up. The total energy is still the same. Stories like these are fairly common now and are very difficult to back up with solid facts. <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[derekmcd]

I have no doubt JonClarke will chime in and clear a few things up. <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[MeteorWayne]

Very interesting stuff docm, thanx as usual! <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[3488]

I heard about something like this a while back.<br /><br />I certainly would not disprove it. Clearly there is evidence of something like this<br />happening, or it would not be published like this.<br /><br />13,000 years ago saw rapid climatic change as the Glaciation over much of North America & Europe loosened<br />its grip.<br /><br />One thing often overlooked, was that this was a period of tremendous storms, as warm air moved north<br />over land & sea that had been so cold for so long.<br /><br />A small comet or meteorite impact, as well as a large volcanic erupition in North America, would have been disastrous.<br /><br />Not only that flora & fauna moving north into areas previously off limits<br />due to ice, would have bought disease, the like of which, early N Americans<br />would have had no immunity (like Malaria or Ebola in Britain for example).<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[dragon04]

VERY interesting. But if a GRB that big and that close happened 13,000 or even 30,000 years ago, shouldn't we notice a BH or pulsar or something very close by?<br /><br />It brings a question to mind though. Let's wave our magic wand and put Eta Carinae closer to Earth. AT a couple thousand parsecs, our atmpsophere will supposedly protect us from the GRB.<br /><br />How much closer would E Car have to be in order to heat the atmosphere (and how does an atmosphere heat from an outside source like a GRB only in one regional location) to 1000 degrees C? <br /><br />My money would be on the low mass (but huge) comet. <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[thamior]

I have to agree with Dragon04 here, though I can't prove that a GRB didn't take place. And, since I'm only an amateur I have a few questions and thoughts:<br /><br />1)The universe was much smaller back then, as it had not expanded as much as it has today. Everything was closer together. IF a supernova had occured close enough to us to heat our atmosphere that much, how far away would it be from us now?<br /><br />2)The supernova would not have occured a few seconds before the GRB occured on Earth. It would be a certain amount of years after the supernova happened that we experienced the GRB, right? If so then, how many years would it take the gamma rays to reach earth?<br /><br />3)considering the fact that it was a supernova, it was a high mass star that exploded, right? The result of a supernova is a black hole? If a black hole were that close to us we would most certainly feel its affects... <br />4)By "interstellar," do you mean it was outside our galaxy? <br /><br />Thanks alot guys <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p>--What is the truth but a wisp of truly un-attainable information.  There is no absolute truth anyways, only false perceptions and misgivings.--     </p> </div>

 

[MeteorWayne]

1)It was only 13,000 years ago out of 4,500,000,000 for the universe (0.0003%). It wasn't that much smaller <img src="/images/icons/smile.gif" /> <br /><br />2) That would depend on how many light years away it was. To have a severe impact it would have to be within a hundred years or so.<br /><br />3) It did not have to be a high mass star. Some supernova are from white dwarves, which need not be too high a mass. One that creates a black hole would be larger.<br />However a black hole has no more mass than a star of the same mass. It's smaller, but from a distance, the gravitational effect is the same.<br />Even the closest star, at 4.3 light years away has an almost immeasurably small effect on the sun, the planets, or even all but the most distant members of the Oort cloud.<br /><br />4)Interstellar means in between stars within the galaxy.<br />Between galaxies would be called intergalactic.<br />Same for interplanetary referring to the inner solar system.<br /><br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[thamior]

Thanks,<br />1) How fast does the universe expand? It is increasing in speed, correct? In 1 billion years what percentage can you estimate our universe will be of its present day size?<br />2)That makes enough sense, but if it was interstellar, that means it is not located within our galaxy correct? <div class="Discussion_UserSignature"> <p>--What is the truth but a wisp of truly un-attainable information.  There is no absolute truth anyways, only false perceptions and misgivings.--     </p> </div>

 

[MeteorWayne]

Sorry, I accidently sent the reply before I was done, and went back and edited it.<br /><br />Check previous reply for answers to #3 and 4.<br /><br />1)Good question, I don't have the numbers at easy recall. I'll have to check for the correct answer. <br /><br />2) see the answer in the post above. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[thamior]

Thanks again ^_^ When you find the numbers I'd prefer that you send me a Pm, because I think I have all the answers I need from the thread and I'm taking it off my favorites list. <div class="Discussion_UserSignature"> <p>--What is the truth but a wisp of truly un-attainable information.  There is no absolute truth anyways, only false perceptions and misgivings.--     </p> </div>

 

[MeteorWayne]

Just cause it's not on your favorites list doesn't mean you can't check in once in a while <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[docm]

As for no remnant; two ways.<br /><br />1. a binary system (red giant and white dwarf) where the accreted mass from the red dwarf is so high it pushes the white dwarf over the Chandrashekar limit. The core collapses igniting the white dwarfs carbon in one big burst. The star blows itself to bits and no remnant remains. <br /><br />2. recently a new class of supernova was discovered; a "pair-instability supernova".<br /><br />In these the temperature in the interior of the star becomes so intense that before the star can run its fusion course high-energy gamma rays form matter-antimatter pairs and annihilate one another. <br /><br />Because gamma radiation is what keeps the outer layers from collapsing inward, with the drop in energy the core is able to fall inward prematurely. This leads to a thermonuclear explosion that shreds the entire star, flinging its entire content into space and leaving behind no remnant whatsoever. <br /><br /> <div class="Discussion_UserSignature"> </div>

 

[thamior]

To MeteorWayne:<br />Alright, no problem ^_^ Its the least I can do for your help.<br /><br />To docm:<br />1) I didn't think about a binary system..<br /><br />2)Great explanation, but I think I'm going to look it up for myself, because I've never heard of that before now.<br /><br />Thanks, <br /> Sean <div class="Discussion_UserSignature"> <p>--What is the truth but a wisp of truly un-attainable information.  There is no absolute truth anyways, only false perceptions and misgivings.--     </p> </div>

 

[docm]

Also; there are other mechanisms for a radiation flux, especially if there are proton currents circumnavigating the galaxy and our system hit one. Let's not forget that the "oh my God particle" came from <i>somewhere</i>. <div class="Discussion_UserSignature"> </div>

 

[derekmcd]

A GBR from anywhere in our galaxy pointed directly at us would be potentially devastating. Our atmosphere would do well in protecting us from the gamma rays themselves, but the energy from the burst is what does the damage. If Eta Car produces a burst directly at us, we are in trouble. <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[MeteorWayne]

It's been a theoritical construct up until now.<br />Google supernova 2006gy <br />It just hit the news within the past few weeks, in fact there are two threads around here that disuss it. One had Eta Carinae in the title. I'll find them. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[thamior]

Interesting.. <div class="Discussion_UserSignature"> <p>--What is the truth but a wisp of truly un-attainable information.  There is no absolute truth anyways, only false perceptions and misgivings.--     </p> </div>

 

[MeteorWayne]

Here's one link <br /><br />Here's the other link <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[thamior]

Thanks ^_^ I've never read anything about Eta Car before. <div class="Discussion_UserSignature"> <p>--What is the truth but a wisp of truly un-attainable information.  There is no absolute truth anyways, only false perceptions and misgivings.--     </p> </div>

 

[MeteorWayne]

Just to point out, eta Car is not the one that is the new type, that's 2006gy.<br /><br />eta Car is a relative neighbor, in our own galaxy, so merits a bit more attention. It hasn't exploded yet that we know of, as of 2:42 PM EDT <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[thamior]

Of course..<br /><br />I hope I'm alive when it does <img src="/images/icons/laugh.gif" /> <div class="Discussion_UserSignature"> <p>--What is the truth but a wisp of truly un-attainable information.  There is no absolute truth anyways, only false perceptions and misgivings.--     </p> </div>

 

[docm]

<font color="yellow">My money would be on the low mass (but huge) comet.</font><br /><br />And this explains the high radiation event how? There was nothing of the kind at the most recent light body impact; Tunguska in 1908. While not as large as the N. American event there should have been <i>some</i> evidence of intense radiation. <div class="Discussion_UserSignature"> </div>

 

[thamior]

Hmm...good point. Anyways, I'm convinced by the answers I got that it was most likely a GRB. <div class="Discussion_UserSignature"> <p>--What is the truth but a wisp of truly un-attainable information.  There is no absolute truth anyways, only false perceptions and misgivings.--     </p> </div>

 

[robnissen]

Two points. 1) Stars that go Super Nova do not always end up as black holes, some are neutron stars, and IIRC some can end up as White Dwarfs, IFF they throw off enough mass when they go Super Nova.<br /><br />2). If we have a direct hit of Gamma Ray jets, such a hit could be harmful to life here from a distance of many thousand light years. Thus there could be numerous candidates to cause this alleged event. I have no opinion on whether the event happened, but it does sound like, at least, interesting speculation.