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DWB1960
05-09-2012, 01:45 PM
Came up in the dinosaur thread but it deserves it's own thread.

The asteroid that killed the dinosaurs:

http://en.wikipedia.org/wiki/Chicxulub_crater

It's mind blowing the impact (pun intended) this had on our planet:

The impact would have caused some of the largest megatsunamis (http://en.wikipedia.org/wiki/Megatsunami) in Earth's history, reaching thousands of meters high. A cloud of super-heated dust, ash and steam would have spread from the crater, as the impactor burrowed underground in less than a second. Excavated material along with pieces of the impactor, ejected out of the atmosphere by the blast, would have been heated to incandescence upon re-entry, broiling the Earth's surface and possibly igniting global wildfires; meanwhile, colossal shock waves (http://en.wikipedia.org/wiki/Shock_wave) would have triggered global earthquakes (http://en.wikipedia.org/wiki/Earthquakes) and volcanic eruptions (http://en.wikipedia.org/wiki/Volcanic_eruption). The emission of dust and particles could have covered the entire surface of the Earth for several years, possibly a decade, creating a harsh environment for living things. The shock production of carbon dioxide (http://en.wikipedia.org/wiki/Carbon_dioxide) caused by the destruction of carbonate (http://en.wikipedia.org/wiki/Carbonate) rocks would have led to a sudden greenhouse effect (http://en.wikipedia.org/wiki/Greenhouse_effect). Over a longer period, sunlight would have been blocked from reaching the surface of the earth by the dust particles in the atmosphere, cooling the surface dramatically. Photosynthesis (http://en.wikipedia.org/wiki/Photosynthesis) by plants would also have been interrupted, affecting the entire food chain (http://en.wikipedia.org/wiki/Food_chain). A model of the event developed by Lomax et al. (2001) suggests that net primary productivity (http://en.wikipedia.org/wiki/Primary_productivity#GPP_and_NPP) (NPP) rates may have increased to higher than pre-impact levels over the long term because of the high carbon dioxide concentrations.

In February 2008, a team of researchers led by Sean Gulick at the University of Texas at Austin (http://en.wikipedia.org/wiki/University_of_Texas_at_Austin)’s Jackson School of Geosciences (http://en.wikipedia.org/wiki/Jackson_School_of_Geosciences) used seismic images of the crater to determine that the impactor landed in deeper water than was previously assumed. They argued that this would have resulted in increased sulfate aerosols in the atmosphere. According to the press release, that "could have made the impact deadlier in two ways: by altering climate (sulfate aerosols in the upper atmosphere can have a cooling effect) and by generating acid rain (water vapor can help to flush the lower atmosphere of sulfate aerosols, causing acid rain)."

Tonekat
05-09-2012, 02:10 PM
That is fascinating! What a planet-changing event.

Kitten Cannon
05-09-2012, 02:12 PM
Yeah, it's funny how we humans are all "zomg, the world is going to end!" sometimes. I mean, if you think about it, it already HAS. Probably a few times.

scott
05-09-2012, 02:15 PM
Yeah, it's funny how we humans are all "zomg, the world is going to end!" sometimes. I mean, if you think about it, it already HAS. Probably a few times.

I agree, it should be,"OMG our species is comming to an end."

fetishfrog
05-09-2012, 02:20 PM
From a human race perspective, that's probably the most important place on Earth, given that we'd likely not exist if it never happened.

Now it's on my bucket list, the cataclysmic version of the "Garden of Eden", if you will.

DWB1960
05-09-2012, 02:31 PM
From a human race perspective, that's probably the most important place on Earth, given that we'd likely not exist if it never happened.


This is what I think about. If that asteroid had been traveling even .00001 MPH slower or faster it would have missed the earth by a large margin. And as you say, the implications of it not hitting are mind boggling.

So we are sitting in front of our PCs today having this chat only because a chunk of rock hit our planet 65,000,000 years ago.

Crazy!

mwc2112
05-09-2012, 02:44 PM
And that might not have even been the most important impact the Earth has seen. The most accepted theory of the creation of the Moon was that a Mars-sized object hit the Earth at exactly the right angle some 50M years after the solar system was formed. No Moon likely means no life at all!

DWB1960
05-09-2012, 02:46 PM
And that might not have even been the most important impact the Earth has seen. The most accepted theory of the creation of the Moon was that a Mars-sized object hit the Earth at exactly the right angle some 50M years after the solar system was formed. No Moon likely means no life at all!

Had never read about this. :eek::eek::eek::eek::eek::eek:

http://en.wikipedia.org/wiki/Giant_impact_hypothesis

fetishfrog
05-09-2012, 02:52 PM
No Moon likely means no life at all!

Well there'd definitely be fewer werewolves and likely no Twilight series. Jury's still out on whether we got the win or not.

DGDGBD
05-09-2012, 02:57 PM
Here's something related to the subject to play around with if you're bored -

http://impact.ese.ic.ac.uk/ImpactEffects/

James M
05-09-2012, 02:58 PM
This may well indeed be not the biggest crater. They think the largest is in Antarctica, measuring at about 500km in diameter vs 170km for the Chicxulub crater. They think this crater may have been associated with another extinction event...called the Mother of All Mass Extinctions. I also didn't know that the extinction of the dinosaurs wasn't the biggest extinction event in history...not by far. In the Permian-Triassic extinction event, 96% of sealife and 70% of terrestrial vertebrate life died. Amazing that the earth can recover...and still yield us!

http://en.wikipedia.org/wiki/Wilkes_Land_crater
http://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extinction_event

DWB1960
05-09-2012, 03:38 PM
Here's something related to the subject to play around with if you're bored -

http://impact.ese.ic.ac.uk/ImpactEffects/

Fun. I feel like Roland Emmerich!

Amazing that the earth can recover...and still yield us!

http://en.wikipedia.org/wiki/Wilkes_Land_crater
http://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extinction_event

More :eek::eek::eek::eek::eek::eek::eek:

1wheel
05-09-2012, 03:47 PM
Gee, It certainly would be unlikely that this could happen again?

This is somewhat disconcerting (Red are Earth crossing BTW).

Asteroid Discoveries (http://www.youtube.com/watch?src_vid=S_d-gs0WoUw&annotation_id=annotation_79355&feature=iv&v=ONUSP23cmAE)

So, I wear one of these on occasion (no, it is NOT a political comment)...

http://i1.cpcache.com/product/420250373/party_like_its_2012_organic_mens_fitted_tshirt.jpg ?color=Black&height=460&width=460