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Antarctic Craters Reveal Asteroid Strike
dhuff writes "Scientists using satellites have mapped huge craters under the Antarctic ice sheet caused by an asteroid as big as the one believed to have wiped out the dinosaurs 65m years ago."
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It could have been an explosion from several adolescent Predators when being overtaken by thousands of Aliens?
"One thing that did happen at exactly the same time was the reversing of the Earth's magnetic field." Darn so the water hasn't always drained the same direction? Does the magnetic field being reversed actually affect anything important?
Prof Van der Hoeven said: "The extraordinary thing about this meteor strike is that it appeared to do so little damage. Unlike the dinosaur strike there is no telltale layer of dust that demonstrates the history of the event. It may have damaged things and wiped out species but there is no sign of it."
Cheers,
Erick
http://www.busyweather.com/
Prof Van der Hoeven said: "The extraordinary thing about this meteor strike is that it appeared to do so little damage. Unlike the dinosaur strike there is no telltale layer of dust that demonstrates the history of the event. It may have damaged things and wiped out species but there is no sign of it."
One thing that did happen at exactly the same time was the reversing of the Earth's magnetic field. There is no other explanation as to why this took place and Prof Van der Hoeven believes it was caused by the impact.
Does this mean we're safe a a few more years
I'd like to think we could do something about this problem, but I wonder if any technology we have could alter the course of an asteroid large enough to be a problem. Do we even have a prototype of something like a fusion rocket that could potentialy move the hundreds (thousands/millions) of tons of mass that these big rocks have?
Have the nuk-lear worryworts made sure that we haven't even researched the possibilities? Best I've ever seen is the occasional schematic of an orion-type starship from decades ago. Screw Ion-Drives. Let's give some money to the big engines...
Quoth the good professor:
The extraordinary thing about this meteor strike is that it appeared to do so little damage. Unlike the dinosaur strike there is no telltale layer of dust that demonstrates the history of the event.
It ploughs through millions of tonnes of ice and snow, then leaves no layer of dust... d'you think it might have, I dunno, melted or something?
More information at The Scotsman, btw.
If they find pyramids under there, stay away from them.
I for one welcome our new asteroid overlords
Hah! Take that Karma!
Obviously, statistically the chance of an individual being killed by a major meteor strike is fairly low, perhaps lower than that of being killed in a terrorist attack and much lower than that of being killed on the roads. But it's the meteor strike that has the potential to kill perhaps 99% of the human race, and this latest evidence seems to suggest that the frequency of such impacts is higher than expected.
Panurge has posted for the last time. Thanks for the positive moderations.
I don't dispute Hans' rigor in studying the issue, but how can the correlation of the impact and the magnetic field reversing lead to the conclusion the impact caused the reversal?
And why even compare this 780K yr old impact to what might've done the dinosaurs in 65m yrs ago? It just would confuse people with poor reading skills (*cough* slashdot readers) and lead them to associate this 780K yr old impact with the extinction of the dinasaurs.
Also, the article attemps to explain why the 65m yr old impact would've caused climactic change whereas the 780k yr old impact would not -- I didn't quite understand their argument of why the older impact caused dust clouds leading to extinction while the newer impact did not -- was it because of the composition of ice vs rock?
"Is it just me, of is that article have the stench of bullshit about it?"
Not at all, but if they claimed the dinasaurs built an earth ship to drill to the core and detonate 4 nuclear bombs, I'd be suspicious.
That's 24 days ago.
The dinosaurs were wiped out on July 28 2004?
"One thing that did happen at exactly the same time was the reversing of the Earth's magnetic field." Darn so the water hasn't always drained the same direction?
Magnetism has nothing to do with the direction in which water flows in a drain. That would be the rotation of the planet.
Does the magnetic field being reversed actually affect anything important?
Yes.
Things like radiation reaching the planet's surface, stuff like that.
You can't take the sky from me...
a lot of people believe that the 65m impact was centered over land NOT covered by ice and snow, as in the central point in which all current continents used to be connected (pangea).
That impact would have crushed mountains and created enormous amounts of dust from them. The 780k impact hit a huge block of ice and snow, i.e. no dust to scatter in the first place. I really doubt it would have affected any land life at all, antarctica being so far from land inhabited by anything more than penguins and stuff. Ocean life probably got pretty roughed up at least close to the impact.
The poor widdle penguins. If they all died, Linus may have picked Walruses instead. Walnix?
Table-ized A.I.
A gravity anomoly is anything other than what you would expect from a continuous, uncratered surface. It would not be something you could measure without very precise instruments.
The ice would definitely prevent large tsunami. I have seen even the lightest coating of snow tame the rough north atlantic.
As far as the meteor causing magnetic pole reversal, I don't see how. The earth's magnetic fields originate in the spinning iron core. Perhaps disturbing the spin slightly might help trigger a field reversal but that would be more likely to occur after an oblique equatorial collision than after a polar strike. The melting of the antarctic ice sheet would not even affect the planet's rotational inertia the way it would if Greenland's suddenly melted. But all of these effects are miniscule. The field reversal timing is almost certainly a coincidence.
"Will future ages believe that such stupid bigotry ever existed!" -- Ivanhoe
Does this match up with the proposed theory that humans went through a short period of being reduced to a very few individuals - the so called 'mitochondrial eve' hypothesis?
Wow! Only 780 thousand years ago?
At that point our hominid ancestors were strolling around southern Africa. By then we had stone tools and the occasional use of fire. That's really recent in a hominid lineage that goes back, what 6 million years? They lived through a 3-7 kilometer asteroid impact! Can you imagine?
Good thing it didn't land a few thousand miles to the north...
However this report raises a lot of questions that it doesn't answer.
First of all, they seem to be talking about a single strike, but they first talk about "the crater" and then later "the holes" and "the craters." Are we talking about one crater or many? Did the person who wrote the article typo, or are the scientists being that unspecific?
Second of all, wasn't the Antarctic continent still near the south pole 780k years ago? That seems to mean that either the meteor hit at a very extreme angle, or it was _far_ out of the elliptic. In either case, it would be a very rare occurance.
On the other hand, magnetic reversals are _not_ a very rare occurance, they happen about once every 700,000 years. Why is he assuming that the very rare occurance caused the frequent and mostly regular occurance? It seems much more likely that it was just a coincidence. "There is no other explanation as to why this took place" yeah, and there is no other explanation for the other several _hundred_ nearly identical events either, because we haven't figured out why they happen yet! So is he proposing that Antarctica gets hit by a giant meteor about every 700k years like clockwork?
Finally exactly how "huge" are these craters, and what were the climatic conditions 780k years ago? If the climate was similar and Antarctica was near the south pole and covered with ice, wouldn't a "huge" strike have melted/dispersed quite a lot of the ice and caused ocean levels to rise?
This Space Intentionally Left Blank
Well, I'm off to filling my tub and experimenting for myself, thanks.
The best possible attitude toward science -- "show me!". Have fun in your tub!
Tubal-Cain smokes the white owl.
But on a serious note, whether or not this is an ordinary fluctuation is irrelevant in practical terms. If the magnetic field weakens enough to wreak havoc on our expectations (and that could affect much more than just compasses, of course), we should be paying attention to it, whether or not it is "insignificant" in terms of the larger time frame of the universe. Human beings ourselves are likely insignificant in terms of the history of the universe.
not true. we have thousands of years of data preserved in pottery, which aligns its metals when heated in kilns..we use that data to make a map of the field. We also have millions of years of data collected from hardened lava flow in hawaii.. so we have plenty of data.
pm
** "It's not my job to stand between the people talking to me, and the ones listening to me." -- Pego the Jerk
In fact it was a preemptive strike; the asteroids found evidence that the dinosaurs were close to developing weapons of mass destruction.
You can't kill everything and everybody unless ~100% lived near the coast AND the water rises faster than people can run including those at the limit of the sea level rise! As for hot spots, like Yellowstone, Google the term "flood basalts" and you will get an idea of what has gone on in the past. See http://volcano.und.nodak.edu/vwdocs/volc_images/no rth_america/yellowstone.html for example. Notice the mention that the calderas get younger toward the east. This ties in with plate tectonics due to ocean floor spreading at the mid-atlintic ridge. If you want to put some models together to test the possiblity of "The Flood" and the likelihood and nature of future catastrophes, understanding plate tectonics is vital. It's bigger than evolution is. Predictions and observations, that is what makes for a good theory.
The only Diluvian stories that make some sense at all are those who interpret the Bbiel less than literally. such as a local inundation.
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Everyone remain calm. I spent countless hours in arcades preparing for such an impact. That's the real reason the dinosaurs died: they didn't have arcades.
"To confine our attention to terrestrial matters would be to limit the human spirit." -Stephen Hawking