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Giant Impact Crater Found In Australia
An anonymous reader writes "One of the largest meteorite impacts in the world has been discovered in the South Australian outback by geothermal researchers. It may explain one of the many extinction events in the past 600 million years, and may contain rare and exotic minerals. The crater is said to have been 'produced by an asteroid six to 12 km across' — which is really big!"
Obviously not in the article.. not even one damn picture of it..
Okay so they give widely varying estimates of the crater's size - assuming the centre value of 120 Km a +/- 60 Km ia one hell of a margin of error. I imagine that the energy released from such an impact is orders of magnitude greater than any nuke we could ever throw at each other. The article metions the release of CO2, but i thought that by definition asteroids were just lumps of rock. So where does the CO2 come from after the impact?
Obviously not in the article.. not even one damn picture of it..
It is very difficult to photograph something that is 80-160 km across and buried under many layers of sediments... that may have something to do with the lack of pictures.
TFA doesn't mention when the discovery was made, so it is hard to say how much time they've had to produce some images for the media.
I can imagine that specialized satellites can scan the area for geological differences. But I imagine that Google Maps shows no sign of this crater at all.
Okay so they say in TFA that the crater has most likely eroded away, but they could have at least shown a map of the region with a yellow circle to indicate where they think it is.
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
TFA doesn't mention a location. There is a roughly circular sort of feature in about the right place and about the right size centred here:
http://maps.google.com.au/?ie=UTF8&ll=-28.614665,141.139984&spn=0.806518,1.234589&t=h&z=10
You can see it better if you zoom out a couple of steps. It's not very well defined, and may just be wishful thinking on my part!
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"You call that a meteorite? THIS is a meteorite!"
Monstar L
This must be where The Lost City of Pnakotus was located!
--
"I have also mastered pomposity, even if I do say so myself." -Kryten
> they could have at least shown a map of the region with a yellow circle to indicate where they think it is.
They said the geothermal researcher who discovered this crater was working in the Cooper Basin, South Australia.
http://en.wikipedia.org/wiki/Cooper_Basin
This is where it is:
http://www.hydrocarbons-technology.com/projects/CooperbasinAust/images/2-cooper-basin.jpg
The geothermal energy project in that area of the world is near the town of Innaminka.
http://en.wikipedia.org/wiki/Innamincka,_South_Australia
http://en.wikipedia.org/wiki/File:Innamincka_location_map_in_South_Australia.PNG
The geothermal energy project is there because the earth's crust at that location is unusually thin.
http://www.smh.com.au/news/environment/hot-rock-power-the-way-ahead/2007/04/11/1175971183212.html
http://www.adelaide.edu.au/adelaidean/issues/9461/news9469.html
The earth's thin crust in that area may actually have something to do with the impact crater.
This is a quite remote part of the world. Desert. There is almost nothing there.
It is not really surprising that this impact crater has not been discovered up until now.
There's an article on the University of Queensland's web site (where the researchers hail from).
The land surface that the asteroid hit is now buried under layers of sedimentary rock and Dr Uysal thinks the original crater most likely eroded away.
"Dr Uysal and Dr Glikson will present their findings at the Australian Geothermal Energy Conference in Adelaide, 16-19 November 2010."
To read more about their research, see their conference paper (pdf). (This may not be specifically on the impact, but on their geothermal research, instead.)
In short, not the biggest, oldest, newest, or any other superlative. Still, given the estimated size of the impact, I'd expect it to have had a major impact on the Earth's weather for quite a while.
That impact crater is dwarfed by some other structures on earth: The Bushveld complex in South Africa is several hundred kilometers across, but it is so old (> 2 billion years = half the age of the earth) that it is not clear how it formed. Either a gigantic volcano, or a gigantic metor impact could have caused it.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Oh, sure, sure, but you really had to hike there before all the tourists discovered it and ruined the local culture.
If you were blocking sigs, you wouldn't have to read this.
Limestone is calcium carbonate, which releases tons of CO2 when burned.
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As a quick guess I'd say the destruction would be limited to a relatively small area of the planet. You'd have total devastation within a radius of maybe a few hundred kilometers, but the rest of the planet would be fine. You wouldn't have ash encircling the planet and blocking out the sun as with a Chicxulub-type impact (which is by far the most devastating effect of a large asteroid impact to life on a planet), although you may still get some smaller Eyjafjallajokull-size ash clouds.
Now if it landed in the ocean you'd have serious mega-tsunamis that would wipe out of a lot of coastal areas all around the world, but again not devastating on a planetary scale.
Just my somewhat-educated guess.
"When information is power, privacy is freedom" - Jah-Wren Ryel
On TV you see lots of computer sims but none look realistic to me. Would there be a light covering the sky so bright you couldn't see it or would it traverse the atmosphere so quick it wouldn't have time to heat up and you really would see this huge space rock impact. And what would the explosion look like? WOuld it be a fireball initially or would you simply see billions of tons or rock being launched into orbit?
A very useful source of information is the Asteroid Impact Effects on-line program: http://impact.ese.ic.ac.uk/ImpactEffects/
Taking their upper size estimate (12 km) and average impact parameters (17 km/sec, 45 degree angle of entry) this would light up brilliantly at around 120 km altitude and get brighter all the way down its 10 second transit to the Earth. However you would probably not want to be anywhere you could actually see its entry. At a distance of 1250 km you would just see it light up on entry on the horizon, and thereafter the glow would be indirect until impact. THEN - part of the fireball which appear ~5 times larger and brighter than the Sun would rise above the horizon and irradiate you for about half an hour. This would be quite uncomfortable - a first degree thermal burn would develop after several seconds, but you get roasted for a hundred times longer than that, or until the fine ejecta thrown into space comes down and starts blocking your light after 10 minutes of so. And an hour after the impact a 12 psi blast wave with tornado-speed 335 mph winds would hit. This would likely be fatal.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
For what it's worth, these craters are probably not as uncommon as people think. I'm sitting inside one right now.
Nobody is saying this is the biggest crater ever created in the solar system.
But, they are saying that anything which creates a crater of that size on Earth is going to make one hell of a mess. From TFA:
In this case, "big" is relative. And, me, I'd call this pretty damned big in terms of what it actually signifies.
You can niggle over the fact that Titan has a bigger crater if you like. Me, I wouldn't want to be around when something like this happened. Have you gotten so jaded with this stuff as to lose track of what it actually means?
Lost at C:>. Found at C.