Posted on 06/02/2006 11:44:43 AM PDT by cogitator
An apparent crater as big as Ohio has been found in Antarctica. Scientists think it was carved by a space rock that caused the greatest mass extinction on Earth, 250 million years ago.
The crater, buried beneath a half-mile of ice and discovered by some serious airborne and satellite sleuthing, is more than twice as big as the one involved in the demise of the dinosaurs.
The crater's location, in the Wilkes Land region of East Antarctica, south of Australia, suggests it might have instigated the breakup of the so-called Gondwana supercontinent, which pushed Australia northward, the researchers said.
"This Wilkes Land impact is much bigger than the impact that killed the dinosaurs, and probably would have caused catastrophic damage at the time," said Ralph von Frese, a professor of geological sciences at Ohio State University.
How they found it
The crater is about 300 miles wide. It was found by looking at differences in density that show up in gravity measurements taken with NASA's GRACE satellites. Researchers spotted a mass concentration, which they call a mascon—dense stuff that welled up from the mantle, likely in an impact.
"If I saw this same mascon signal on the Moon, I'd expect to see a crater around it," Frese said. (The Moon, with no atmosphere, retains a record of ancient impacts in the visible craters there.)
So Frese and colleagues overlaid data from airborne radar images that showed a 300-mile wide sub-surface, circular ridge. The mascon fit neatly inside the circle.
"And when we looked at the ice-probing airborne radar, there it was," he said today.
Smoking gun?
The Permian-Triassic extinction, as it is known, wiped out most life on land and in the oceans. Researchers have long suspected a space rock might have been involved. Some scientists have blamed volcanic activity or other culprits.
The die-off set up conditions that eventually allowed dinosaurs to rule the planet.
The newfound crater is more than twice the size of the Chicxulub crater in the Yucatan peninsula, which marks the impact that may have ultimately killed the dinosaurs 65 million years ago. The Chicxulub space rock is thought to have been 6 miles wide, while the Wilkes Land meteor could have been up to 30 miles wide, the researchers said.
Confirmation needed
Postdoctoral researcher Laramie Potts assisted in the discovery.
The work was financed by NASA and the National Science Foundation. The discovery, announced today, was initially presented in a poster paper at the recent American Geophysical Union Joint Assembly meeting in Baltimore.
The researchers say further work is needed to confirm the finding. One way to do that would be to go there and collect rock from the crater to see if its structure matches what would be expected from such a colossal impact.
Yeah, like this might have been when the rocks were mating.
bump
Any questions?
Oooookay... Step *away* from the keyboard and seek help immediately.
From: Astrobio.net;
At the time of the K−T extinction, India was an island located over the Reunion hotspot. Hotspots are fixed points where hot material from the mantle rises to the Earth's surface. This underground welling flooded portions of India with a vast amount of lava. Today, these cooled lava fields are called the Deccan Traps.
The slow outpouring of Deccan lava probably began a few million years before the K−T extinction. Then about 65 million years ago, the trickle became a torrent.
I love science and am an avid reader of Popular Mechanics. I've worked in the scientific field for 7 years now. Hell, I've even worked on some of the spectroscopic equipment used to identify materials from core samples that theoretically didn't originate on earth. In fact, I tend to post scientific articles here on FR from time to time. Scientists, to me, let the data speak where the data speaks and keep silent where the data is silent.
The mere fact that they just discovered that another meteor theoretically hit the planet is enough to relegate the whole "dinosaurs were killed by a meteor" theory back to the "theory" category where it belongs.
Birthplace of: aviation, banana split, 6-pack plastic rings, 1st strip shopping center.
Simple, just because there isn't a better answer doesn't make the one you've got right, unless it's a multiple choice test.
Feel free to share with us why my comment is laughable. We have scientists protesting to have other scientists fired because they aren't convinced that a 1 degree F increase in the planet's temperature is proof of irreversible global warming. As far as I know, the increase in carbon in the atmosphere hasn't been proven to be a cause of global warming, a result of it, or irrelevant, but a whole lot of scientists are advocating reducing carbon emissions to the point of bankruptcy. I think that the Scientific Method has been thrown out the window in lieu of advocacy.
Around here, one simply says THE University,
meaning Mr. Jefferson's Academic Village.
Ahhhh, answered my own question. It is so hard to take "scientists" seriously these days. [your bolding]
How does someone being honest by saying "may have" when he's not 100% sure decrease his credibility or gravitas?
I think that's a song on the latest Enya album.
Because of the first time the subject was mentioned, it was mentioned definitively.
The crater, buried beneath a half-mile of ice and discovered by some serious airborne and satellite sleuthing, is more than twice as big as the one involved in the demise of the dinosaurs.
I'm glad to limited the set to just self-promoting doofuses. I can accept that. Just like I can accept that all men of religion/philosophy are not Jimmy Swaggert.
Religion and science are two different things with two different goals. The constant quest by people to find some unified model of reality that encompasses both is the right quest, but too many think they have the answers already on both sides, in my opinion.
No, he doesn't. You might want to work on your reading comprehension.
First, nowhere is it declared to be "definitive". The lack of qualifiers doesn't magically turn it into something said "definitively". Anyone who is even remotely familiar with scientific writing knows that all statements have an unspoken asterisk on them, attaching a clause to the effect, "scientific conclusions are provisional and not necessarily the last word (nor even unanimous), they are subject to change if new evidence warrants a revision, etc.". Thus even flatly saying "A is B" is shorthand for something along the lines of, "the evidence at this point indicates that A is B to a reasonable degree of confidence, such that we can take it as a provisional conclusion for now even though nothing in science ever reaches 100% certainty", and is *very* different from a statement of the form "A is definitively B" -- when something in a scientific context is meant to be declared definitively, it is *EXPLICITLY* stated to be so in order to not be confused with the shorthand language described above.
Worse, however, you have misread the actual statement. You mischaracterize it as "a meteor killed the dinosaurs", when in fact it actually says "the one involved in the demise of the dinosaurs". The astute reader will note the vast difference between the two phrases. While it may indeed be somewhat premature to declare that the Chicxulub meteor "killed" the dinosaurs, as in was the sole or primary cause of their death, it is *NOT* an overstatement to say that it was *involved* in their death, as in one of the contributing factors.
You got snotty with the writer for merely writing that the Chicxulub meteor was *involved*, when that seems an extremely uncontroversial statement -- even those who doubt that it "caused" the dinosaurs' extinction don't deny that it had *some* involvement in the totality of the conditions which pushed the dinosaurs over the edge to extinction.
So in short, what are you bitching about?
if you bother to read further into the flawed article, he takes it back.
No, he doesn't. Again, you might want to work on your reading comprehension.
Later he writes, "the impact that may have ultimately killed the dinosaurs". This does not contradict his first statement. It's just saying that the meteor *may* have itself killed the dinosaurs (latter statement) but even if it didn't it was still at least *involved* in their death to some degree (former statement).
And while it's true that the writer quotes someone *else* (Ralph von Frese) using the phrase, "the impact that killed the dinosaurs", the writer can hardly be faulted for someone else choosing to view it differently -- this is not an example of the *writer's* alleged inconsistency, which you have falsely accused him of. And as for von Frese's comment, that too is not any statement of "fact" or "definitiveness", because yet again there's the unspoken "disclaimer clause" which is a "given" in any statement by someone speaking in a scientific context, unless their words are such as to explicitly override the disclaimer.
Yes, the snotty comments are mine,
...and without cause. Or should I say, their only cause was that big chip on your shoulder which you have for some unknown reason.
but they wouldn't be there if the article didn't present an unproven theory as fact.
It didn't, actually. Nowhere does it say, "it's a fact that...etc."
I love science and am an avid reader of Popular Mechanics.
Then you might want to work on your animosity issues you clearly have with it.
I've worked in the scientific field for 7 years now.
Gosh, a whole seven years, eh?
Hell, I've even worked on some of the spectroscopic equipment used to identify materials from core samples that theoretically didn't originate on earth. In fact, I tend to post scientific articles here on FR from time to time.
Then how do you explain that chip on your shoulder?
Scientists, to me, let the data speak where the data speaks and keep silent where the data is silent.
This is a vast oversimplification. The data do not "speak", someone has to describe what the data seems to indicate and why.
The mere fact that they just discovered that another meteor theoretically hit the planet is enough to relegate the whole "dinosaurs were killed by a meteor" theory back to the "theory" category where it belongs.
That statement makes absolutely no sense. If anything, the discovery of yet another large meteor impact crater correlated with the time of another mass-extinction event strongly bolsters the case that large impacts are a key factor in mass extinctions. One by itself might have been a coincidence (i.e., the Chicxulub meteor might have "just happened" to occur very close to the time of the events which "actually" caused the KT extinction that wiped out many species including all the dinosaurs, but not been a key factor). However, the discovery of a *second* large impact at the time of *another* large mass extinction makes the "coincidence" hypothesis far less credible, and the "big meteors cause big die-offs" hypothesis far more validated.
Furthermore, you say "back to the 'theory' category" as if you are under the mistaken impression that some scientific theories get to "graduate" to fact. No, they don't. "Theory" is the highest category of explanation in science. They don't ever become "facts". It's just that some theories are much more validated than others. You might want to actually learn more about the "scientific method" before you deign to critique its use again, as you attempted to do in post #34. Or at least advance your understanding of it beyond the "7th grade" level you boast of.
Additionally, you drew broad, snotty, derogatory conclusions about "scientists" based on the words chosen (which you misread anyway) by a *journalist*. How exactly do you justify that?
Because of the first time the subject was mentioned, it was mentioned definitively.
Again, no, it wasn't.
I could have sworn I already posted this, but I don't see it anywhere
Mentioned definitely as "the one involved in the demise of the dinosaurs." not as "the one that killed the dinosaurs."
That's a big difference.
[No, it isn't. But I need a good laugh today, feel free to share with us your "reasons" for saying such a goofy thing.]
Simple, just because there isn't a better answer doesn't make the one you've got right, unless it's a multiple choice test.
He didn't say that it did. Once again, I must refer you to that "reading comprehension" thing.
And again, I must implore you to update your knowledge of science to beyond the "7th grade" level. No one is foolish enough to think that the lack of a better explanation makes the current one "right", as you wrongly mischaracterize it, but it does however make the current explanation (if it is clearly better than other existing alternatives) the one that is provisionally adopted (while keeping in mind its current shortcomings, if any) until a better one comes along. This is actually one of science's strengths, not one of its weaknesses.
Feel free to share with us why my comment is laughable.
Because the scientific method is alive and well, and continues to be so whether or not you think some poster on FreeRepublic might have misused it or not bothered to use it.
We have scientists protesting to have other scientists fired because they aren't convinced that a 1 degree F increase in the planet's temperature is proof of irreversible global warming. As far as I know, the increase in carbon in the atmosphere hasn't been proven to be a cause of global warming, a result of it, or irrelevant, but a whole lot of scientists are advocating reducing carbon emissions to the point of bankruptcy.
That still doesn't make the scientific method "dead", even if some people happen to have abused it. Is Capitalism "dead" because of Enron in your world?
I think that the Scientific Method has been thrown out the window in lieu of advocacy.
The fact that *some* people throw it out the window in lieu of advocacy hardly makes it "dead", it just means that not everyone uses it who should.
You might want to cut down on your hyperbole, and crank down your tendency to "drama queen" things. The fact that a *journalist* writes a few sentences you managed to misread doesn't justify your snotty attacks on "scientists" , and the fact that a few people engage in propaganda instead of real science doesn't mean that the "scientific method is dead".
Are you going to cite any examples of the life of the Scientific Method in present day science or are you just going to keep attacking me and pinging all your pals?
How ya gonna handle #79, Ich? Looks like a show stopper.
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