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An artist's impression of a 6-mile-wide asteroid striking the Earth. Scientists now have fresh evidence that such a cosmic impact ended the age of dinosaurs near what is now the town of Chixculub in Mexico.
By Charles Choi
LiveScience
The idea that a cosmic impact ended the age of dinosaurs in what is now Mexico now has fresh new support, researchers say.
The most recent and most familiar mass extinction is the one that finished the reign of the dinosaurs — the end-Cretaceous or Cretaceous-Tertiary extinction event, often known as K-T. The only survivors among the dinosaurs are the birds.
Currently, the main suspect behind this catastrophe is a cosmic impact from an asteroid or comet, an idea first proposed by physicist Luis Alvarez and his son, geologist Walter Alvarez. Scientists later found that signs of this collision seemed evident near the town of Chicxulub (CHEEK-sheh-loob) in Mexico in the form of a gargantuan crater more than 110 miles (180 kilometers) wide. The explosion, likely caused by an object about 6 miles (10 kilometers) across, would have released as much energy as 100 trillion tons of TNT, more than a billion times more than the atom bombs that destroyed Hiroshima and Nagasaki.
However, further work suggested the Chicxulub impact occurred either 300,000 years before or 180,000 years after the end-Cretaceous mass extinction. As such, researchers have explored other possibilities, including other impact sites, such as the controversial Shiva crater in India, or even massive volcanic eruptions, such as those creating the Deccan Flats in India.
Courtesy of Paul Renne
Doctoral student Bill Mitchell collects a volcanic ash sample from a coal bed just above the final dinosaur extinction level.
Timing of an impact
New findings using high-precision radiometric dating analysis of debris kicked up by the impact now suggest the K-T event and the Chicxulub collision happened no more than 33,000 years apart. In radiometric dating, scientists estimate the ages of samples based on the relative proportions of specific radioactive materials within them. [Wipe Out: History's Most Mysterious Mass Extinctions]
"We've shown the impact and the mass extinction coincided as much as one can possibly demonstrate with existing dating techniques," researcher Paul Renne, a geochronologist and director of the Berkeley Geochronology Center in California, told LiveScience.
Courtesy of Klaudia Kuiper
Near Jordan, Mont., rock layers expose the level (lower arrow) where dinosaurs and many other animals and plants went extinct. The arrows point to coal beds that contain thin volcanic ash layers that were dated.
"It's gratifying to see these results, for those of us who've been arguing a long time that there was an impact at the time of this mass extinction," geologist Walter Alvarez at the University of California at Berkeley, who did not participate in this study, told LiveScience. "This research is just a tour de force, a demonstration of really skillful geochronology to resolve time that well."
The fact the impact and mass extinction may have been virtually simultaneous in time supports the idea that the cosmic impact dealt the age of dinosaurs its deathblow.
"The impact was clearly the final straw that pushed Earth past the tipping point," Renne said. "We have shown that these events are synchronous to within a gnat's eyebrow, and therefore, the impact clearly played a major role in extinctions, but it probably wasn't just the impact."
The new extinction date is precise to within 11,000 years.
"When I got started in the field, the error bars on these events were plus or minus a million years," added paleontologist William Clemens at the University of California at Berkeley, who did not participate in this research. "It's an exciting time right now, a lot of which we can attribute to the work that Paul and his colleagues are doing in refining the precision of the time scale with which we work."
Cosmic Log: Asteroid closes in for close encounter — and a swift kick
Although the cosmic impact and mass extinction coincided in time, Renne cautioned this does not mean the impact was the only cause of the die-offs. For instance, dramatic climate swings in the preceding million years, including long cold snaps in the general hothouse environment of the Cretaceous, probably brought many creatures to the brink of extinction. The volcanic eruptions behind the Deccan Traps might be one cause of these climate variations.
"These precursory phenomena made the global ecosystem much more sensitive to even relatively small triggers, so that what otherwise might have been a fairly minor effect shifted the ecosystem into a new state," Renne said.
The cosmic impact then proved the death blow.
"What we really need to do is to understand better what was going on before the impact — what was the level of ecological stress that existed that allowed the impact to be the straw that broke the camel's back?" Renne said. "We also need better dates for the massive volcanism at the Deccan Flats to better understand when it first started and how fast it occurred."
The scientists will detail their findings in Friday's issue of the journal Science.
Follow LiveScience on Twitter @livescience. We're also on Facebook and Google+.
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ANd, still more turds can't help themselve, by dropping Obama's name into their BS!
Crazy, neo-nut bastards...!!
i just thought god got sick of playing with his dinosaurs so he got rid of them. The bible can be found in the fiction section, over by the harry potter books. haha
I will be smiling in the Bosum of Abraham while you roast for you foolishness. I Timothy 6:20
Ya I heard ole Abe had some pretty massive moobs
These are either really smart MO FO's or get some really good weed!!!
Knowing scientists, quite possibly both.
Uh, we already knew this. Was this article taken out their archives?
No, the point here is that we have a much more precise estimate of timing, and therefore much stronger evidence to support the theory. That's how science advances.
jock.....This kind of sciences "advances" very similar to Al Gore's claims of man made Global Warming.......... er...make that Climate Change. It is interesting how people who believe themselves to be smart will so readily believe ANYTHING which supports and/or proves their beliefs, while rejecting ANYTHING (including facts or truth) which is in opposition to their beliefs.
In the past few decades the 2 major political parties constantly use this strategy against one another. Saul Alinsky's strategy of repeating over and over, again and again, an assertion, accusation, or political "talking point," until it was generally accepted as fact seems to be working well. The Democratic Party has embraced Alinsky's strategy, successfully villifying members of the GOP, conservatives, tea party people, and most anyone else who disagrees with their political positions, representations or opinions.
NEWSFLASH: It is a statistical impossibility for two (2) differing ideologies to ALWAYS be right or wrong.
Yeah, see, the funny thing is, just about everyone on Earth has that tendency. Once we're convinced of a conclusion, we like to stick with it even in the face of opposing evidence. This is true both of people who think they're smart (a LOT of people think they're smart) and people who can admit they're not that smart.
Science allows us to approach matters from a truly objective standpoint. It doesn't guarantee it always, because it's still performed by humans and humans are prone to bias, but it does a much better job than, say, politics, which you are bringing up for I don't know why.
I'm not saying that science is always right, but it is not an ideology (in case that's what you were suggesting).
I'm sure that Mr. Spock would argue that there are NO "Objective" humans, therefore no objective human scientists. Peer-reviewed science is the best standard we have. Establishing where to place our cut-off for rejecting the Null Hypothesis in favor of the Alternative Hypothesis is often dependent on the wishes of the scientist. Scientists are not immune to "group-think" merely because their gray matter is better organized than most of ours.
Witness Heidi Cullen, PhD of the Weather Channel, who said on-air that anyone who does not agree with her interpretation of Global Warming should be dis-barred from the American Meteorological Society. Unfortunately, the CEO of the Weather Channel, also a meteorologist, disagreed. Her regular segment got yanked.
I think there's also what is called the "bias of only publishing positive results" or something like that. Any Biostatisticians out there?
The point is that scientists are as human as the rest of us. "Absolute Objectivity" is a myth...
The religious among us have every right to believe what they want no matter how ridiculous (freedom of religion)
However, the non-religious have every right to make fun of their religious beliefs (freedom of speech)
Of course having the Right to do something does not always make it Wise.
jock
I just find it hillarious that religion is the one facet of people's lives where the search for truth and knowledge is discouraged
When all is said and done, organized religion will go down as the biggest boondoggle in the history of man
No, religion is not discouraged, but rather the opinion that there is only one religion and only one truth and knowledge is discouraged.
Why is this, Unforgiven?? Seems to me like this is POLITICAL CORRECTNESS in excess. In reality, people should be able to offer their opinions and/or debate one another without concerning themselves with being demeaned, harshly criticized, or insulted by those who disagree with them. Unfortunately, there are those among us (YOU for example) who are unable to offer an opinion without attacking those who disagree with your ideology. By the way, "When all is said and done.............." it might work out differently. Think about it.
LOL...where do these so-called scientists get their data???? The earth is only 6,000 years old!!!!!
So, the dinasours were stoned with heavy metal all spaced out???
Because the greed was so great it wiped out the entire economy???
In the blink of an eye????
I'm sorry. I can't stop laughing...
I know I'm stupid but mankind ( the comments) are beyond stupid...
If an asteroid is moving at 8 times the speed of a bullet, it's going pretty fast.
I would only believe this if these so called scientists put their head inside a hat and a hand on a bible and told me that god showed them the vision of this happening, only then I would believe all this rubbish and could be sure that they are telling me the truth.
Really? That's all it takes to convince you that something is true? Claim that it was the word of God while touching a book (not sure where the hat comes in, but that doesn't seem like such an impediment either)?
You do realize that any old liar could just as easily say that as tell you that the sky is red, right?
Then it would only be a "hat trick"
hahaha ok, just change the word hat for a$$ and you might get my point, but thanks for letting me know that there are such people out there so evil that would try to convince me that the sky is red, i will try to wach for that.
i hope the 6000 year old thing is a joke or sarcasm, people cant be that mind numbingly dumb... can they?
Yes they can and many are. However, I do think most that are posting here about the 6000 year old earth are just joking/trolling.
I think most here missed the point, most scientific jobs are funded by federal grants, do you want you're tax dollars going to research that tells us when and how T-REX died. I don't care, feed a starving youngun somewhere.
Yes I do, we have plenty of money to help out people as well as fund the relatively miniscule amount that goes to pure science research.
I think you missed the point, DOOKSUX; feeding people who can't care for themselves is temporal and ultimately useless. Scientific research permanently adds to the sum total of human knowledge and advances our race's understanding of the universe, a goal far, far more important than feeding hobos. I mean, hopefully we can do both, but if not I'll take the science any day.
SF Accountant......"Scientific research permanently adds to the sum total of human knowledge and advances our race's understanding of the universe, a goal far, far more important than feeding hobos."..Say WHAT?? It's no wonder why intellectual giants like YOU keep voting for Nancy Pelosi. Does the title HYPOCRITE sound familiar, SF Accountant? Next time you look at your face in the mirror you will be viewing one!
I don't vote for Nancy Pelosi. I'm a libertarian.
Surprising that a scientific article can become a debate or religious beliefs. The best thing for this planet is a repeat. That way we eliminate our debt, crime and assault rifles.
Animals take what they need and no more. Allow the planet to replenish what is taken. Man consumes and returns nothing.
GBA
Animals take all they can, actually. See any case of species being introduced into foreign environments and overwhelming the local animals. They are no more given to restraint than humans are, and the planet only "replenishes" what it can based on what the animals leave behind, which isn't always enough (for example, currently a parasitic beetle is killing off entire forests in Canada).
They are limited only by their tiny intellects and primitive forms. There is absolutely zero reason to believe any given animal would be more responsible and conservative if they could manage mass explotation of resources as humans do.
People who think that humans are philosophically different from animals are right: humans are the only animals, after all, smart enough to understand philosophy at all. In terms of our motivations, we're the same.
Those homosexual dinosaurs paid for their deviant behavior when the cities of Flintstones and Rubble were destroyed by the asteroid.
Asteroids! Boo! Mine hurt so bad sometimes I have a hard time sitting on the toilet.
Mother nature and the universe sure have interesting ways of taking care of itself.....I can only conclude that the bi-pedaling human is next!......woo- hoo!.......................Yawn!!!!!!
Well SumDay all I can say is, nice to read an article written by one who uses his head
Mass executions, beheadings, 9 year-olds having babies, maybe that asteroid hit Mexico a few million years too early.
What you have put for here is a hypothesis not proven fact. Thus you cannot state factually that the circumstances described in this article are precisely true. In order for this hypothesis is to validated this theory must be replicated under all conditions as described and since to the best lof my knowledge there are no dinosaurs in existance today there is no way the positively prove the article's premise.
A scientific hypothesis is a proposed explanation of a phenomenon which still has to be rigorously tested. In contrast, a scientific theory has undergone extensive testing and is generally accepted to be the accurate explanation behind an observation.[1] A working hypothesis is a provisionally accepted hypothesis proposed for further research.[2]
There are descendants of the dinosaurs alive today. We call them birds. Pretty convincing evidence if you have an open mind that is capable of understanding facts. The theory of evolution is the best interpretation of all the observable facts.
http://en.wikipedia.org/wiki/Origin_of_birds
" In order for this hypothesis is to validated this theory must be replicated under all conditions"
Nonsense; we infer what happened based on the evidence, jsut like we do in solving any other mystery or crime, etc.
I had some dinosaur last night for dinner. It was pretty tasty.
I heard dinosaurs taste just like chicken. Is this corret, AirThief?
I heard they sell mammoth steaks in the artic. Must be pretty freezed dried by now though.
@jock59801
Have you read the bible page to page? - NO
If you READ it, you will find things said in the past is HAPPENING NOW. From Prophecy, to future judgements. If you think it's fiction, then there is a judgement for you when the time comes. But why should I be telling you the Heathen this, you don't believe in it, but that will not save you.
Hope you consider coming to the truth and I do NOT mean Christianity.
We all search for the truth in our own ways.
Have you ever read the Convent of Steel, mugen? I didn't think so. It presages events even more closely than the Torah, and speaks of Man's ascension to Mars, where the first great cults of the Omnissiah will be raised and began to spread across the galaxy.
Your truth is nothing but one of a dozen bundles of lies damning your spirit to its primitive origins! Surrender your corrupt, weak faith and embrace the Machine God! Your flesh is nothing but a brittle, rotting prison! Only through the purity of the machine can we find salvation!
All glory to the Omnissiah!
You are very, very sick, SF Accountant! It appears your caretakers at the asylum are not making any progress with you.
Why do my memory banks tell me that these depressions were spotted on one of the Apollo missions as were a number of features in the Sahara Desert...So did these two actually "Discover" this, or were just "Following up" on what the photogrpah records for the Apollo missions already told us.....
The Chicxulub Crater has been known for a long time. I think it was first discovered by geologists looking for oil or something like that. After all, that's where most of the money for geology comes from.
Here's the history of the discovery.
http://en.wikipedia.org/wiki/Chicxulub_Crater
Scientist have evidence that man and dinosaurs walked the earth at the same time. Their footprints have been found in a river bed in Texas.
My question is "if the dinosaurs were killed off by an asteroid, why wasn't the humans killed off"?
People should really put a little winking face on or something so we can tell which ones are kidding.
I know, right? A few /sarcasm tags would be helpful! I don't know where to put jokes and where to put rebuttals!
Because it was NOT asteroids that killed them. Dion bones would be vaporized by the heat if an asteroid hit them just like throwing a person into molten steel. There are giant humans exhumed who are nephilum. Dinos were forced to fight to the death by God because of their existence destroying the earth and killing off the humans. The Fallen Ones created these foul beasts in the Book Of Jubiliees. This not a Christian perspective, this a man in the spirit of the truth of the most high god.
See? Now how the blazes am I supposed to tell if he's joking or if he really believes that the Allmighty forced dinosaurs into a massive prehistoric gladiator tournament? Did he make that up on the spot? Did he actually read the theory about how the meteor killed off the dinosaurs before coming up with that absurd refutation that assumes that ALL dinosaurs were killed by the meteor impact directly? I don't know!
Just read The Book of Jubliees and The Book of Enoch sir and make your decision. The Catholic church tries to hide these books. Sir I did not make this up. Asteroids has massive amounts of temperature heat, so why the dino bones still stand if asteroids are hotter than volcanoes? when you are creamated you turn to ash right? So why didn't the dino bones turn to ash? Book Of Jubilees is your answer.
mugen, anything in the local area DID turn to ash, or was otherwise disintegrated or melted. Probably for many hundreds of miles. But it's a big planet, and there were plenty of animals with bones elsewhere.
So you're not joking, right?
The actual impact of the asteroid only has an effect on a small area of terrain. Relatively few dinosaurs would be killed directly and immediately from the impact or the heat. If you want to learn more about that you can actually read the theories surrounding asteroid impacts, because you obviously haven't.
But dinosaur fossils come from dinosaurs that have died all throughout their existence. Why would you assume that all dinosaur bones uncovered ever were from dinos that died from the meteor? That's absurd.
No James , humanoids have only been around for the last million years or so. We humans descended from small mammals that were burrowers which survived the conditions after the impact.
http://paleo.cc/paluxy.htm
It's funny how Atheists slam The Torah yet will not utter a foul word on The Koran both Holy and Noble. Or The Book of The Dead or any other Pagan doctrine. You Atheists are an arm for Satan.
How can we an arm for an entity that we deny? Satan is no more real than God.
And BTW, I've never met an atheist that doesn't deride all holy texts as nothing but neat stories, including the Koran and Book of the Dead. Perhaps you just don't involve yourself in many of those conversations, so you don't see them? Just a thought.
Sir,
By denying God does not exist is the arm of Luicifer because that what Luicifer wants. We all once were Chiristians and Catholics and we know that crap does not fly because of the lies and manipulation they tell.
Question? Why does the Federal Government put all resources into denying God and The Torah? If it's a fairy tale, then why focus resources denying it? We can just write it off as like Greek mythology. There is truth to the bible if people come up misssing attempting to unearth truth about what happened in biblical times? Think about it. Not telling you to accept it, but weight it my good sir.
Mugen needs to have an enemy of his group, so he can externalize his aggression. It's pretty normal, but banal to the point of being boring.
mugen, we embrace all of the wisdom that can be found in any of ancient texts, and reject all of the nonsense. It doesn't matter which ancient texts, because they are all written by the same human species, all searching for the truth in their own way.
"Why does the Federal Government put all resources into denying God"
It doesn't. it's job is to not mention any gods at all, and let the people decide for themselves. That's what the separation of church and state is all about.
Last time I checked this nation was under the assumption of GOD. But it's not, it's the New Babloyn that will be destroyed in Rev 18. Then why do you money say "IN GOD WE TRUST", not GODS but "GOD." I'll be waiting for your answer sir.
Then good for him. So what?
Actually, no, that's entirely false. I mean, up to the lies and manipulations part, but that can be applied to any religion.
I don't see the government putting resources into denying it. And in fact, I get exasperated when government resources are even used to DEBATE the topic, such as whether manger scenes are allowable on public property and so on. Do you have an actual example?
And we do, mugen. We do.
Because somebody thought that would be a neat thing to put on the dollar. Same with the pledge of allegiance.
My question is why you think that's some kind of proof? They're just words, of no more significance than any given rant on this comment board.
"Then why do you money say "IN GOD WE TRUST", not GODS but "GOD." I'll be waiting for your answer sir."
Because fundamentalist anti-communists in Congress in the 1950's put it on there to make a political statment, and nobody has bothered to try and get it removed.
"Last time I checked this nation was under the assumption of GOD."
That is your belief. Period.
The eucated fools have expressed their opians now for the truth about how it really happened a little old mouse
(I mean old he had lostall his teeth) found some chilli beans a mexician had thrown out ate them farted and gassed all living creatures to death (scrasm intended)
An asteroid was the cause of dinosaurs being extinct? Great, now they're going to ban asteroids.....or just assault asteroids.
No just the number of asteroid remnants within a given asteroids field of travel.
Gawd I wish they'd at least ban assault morons. I know we'll never get rid of all morons.
I think we could all agree that multiple-asteroid clips should be discouraged.
Nonsense. If I want to own a rocket-propelled asteroid, then that's my non-God given right!
And in other news, I am taking delivery next week on my flying car. George Jetson is going to deliver it personally.
I really wish reporter/journalists would stop using "TNT" to describe how powerful a "blast" was/is. Do you really think the average person can imagine what "1 TRILLION TONS OF TNT" is like when it explodes? No. Do you think the average person could imagine what 100,000 Hiroshima Atomic Bombs is like when they "explode"? YES!
Time to update the lingo to the 20th century, at least!
I don't think the average person could imagine either one, but your point is well taken. It would probably be more useful to describe what the effects of the particular explosion were, and leave it a that.
I personally am around more A-bombs than TNT so I would appreicate it as well.
I wish they'd tell how many olympic-size swimming pools it would heat
I wish they would have told us how many licks it takes to get to the center of a tootsie pop? Ah 1......ah 2.....