That’s A Big Hole
Scientists have discovered an enormous crater under the ice in Antarctica. Believed to be related to the Permian-Triassic extinction event, the crater may have been formed by an object as large as 30 miles across.
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.
300 miles across. That must have been some lightshow.
By Blackhawk, Friday, 2 June , 2006 @ 11:31 pm
Oh great. And I suppose that’s Bush’s fault too. No, wait…it could be America’s fault…
I blame the pengiuns. I think they called this thing in to wipe out the polar bears of Antartica in a raging struggle for dominance 300 million years ago…that’s why you don’t see polar bears there anymore!
Sorry, that’s what I get for speed reading while scrolling down the site…stories kind of ran together…
By Blackhawk, Friday, 2 June , 2006 @ 11:34 pm
Actually, now that I think about it…I wonder if the alien-eating duck is somehow related to all this…alien-eating ducks, meteor-guiding penguins, drunken monkeys, Blue Crab Boulevard…man, that DaVinci Code sucked.
By Gaius, Saturday, 3 June , 2006 @ 6:02 am
We’re happy to supply the fodder for the next conspiracy theory!