World’s Largest Asteroid Crater Unearthed in Australia

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Scientists have discovered evidence of a 250-mile wide crater in central Australia they believe was created by a colossal asteroid hundreds of millions of years ago.

The largest impact zone ever discovered is no longer visible on the Earth’s surface, researchers from the Australian National University said in a statement Monday, but could be identified by evidence buried deep in the earth’s crust.

The scientists had been drilling for another geothermal research project when, by chance, they came across rock layers that had been turned to glass, which usually signifies a high-energy impact. Their findings, published recently in the journal Tectonophysics, contributes to the understanding of the Earth in prehistoric times.

“Large impacts like these may have had a far more significant role in Earth’s evolution than previously thought,” said lead researcher Andrew Glikson. Still, the exact details of when the impact occurred remain unclear. While the rocks surrounding the impact zone are around 300 million years old, scientists said they have not yet found a similar layer in other sediments the same age.

“It’s a mystery — we can’t find an extinction event that matches these collisions,” Glikson said. “I have a suspicion the impact could be older than 300 million years.”

PHOTOS: This Astronaut's Images of Earth Look Like Beautiful Abstract Paintings

Harsh land. Windswept valleys in northern #Africa
"Harsh land. Windswept valleys in northern #Africa"—Alexander Gerst via Twitter on July 6, 2014Alexander Gerst—ESA
Land use in South Africa, you can see where water is.
"Land use in South Africa, you can see where water is."—Alexander Gerst via Twitter on July 9, 2014.Alexander Gerst—ESA
Irrigation in the #Sahara #Desert looks like a challenging task from up here... #BlueDot
"Irrigation in the #Sahara #Desert looks like a challenging task from up here... #BlueDot"—Alexander Gerst via Twitter on July 28, 2014Alexander Gerst—ESA
An open history book of our planet: the #Sahara Desert
"An open history book of our planet: the #Sahara Desert"—Alexander Gerst via Twitter on July 26, 2014Alexander Gerst—ESA
An open history book of our planet: the # Sahara Desert
"An open history book of our planet: the # Sahara Desert"—Alexander Gerst via Twitter on July 26, 2014Alexander Gerst—ESA/SIPA USA
Close-up of gigantic Salar of Uyuni in Bolivia. You can even see the salt fields and the 'Cactus Island'
"Close-up of gigantic Salar of Uyuni in Bolivia. You can even see the salt fields and the 'Cactus Island'."—Alexander Gerst via Twitter on July 15, 2014.Alexander Gerst—ESA
The #Moon was still behind the horizon. A #FataMorgana of atmospherical refraction #BlueDot
"The #Moon was still behind the horizon. A #FataMorgana of atmospherical refraction #BlueDot"—Alexander Gerst via Twitter on July 14, 2014Alexander Gerst—ESA/SIPA USA
When I took this photo, I was sure these are clouds. But now I'm not so sure... #BlueDot
"When I took this photo, I was sure these are clouds. But now I'm not so sure... #BlueDot"—Alexander Gerst via Twitter on July 7, 2014Alexander Gerst—ESA
Nasa: Astronaut Alexander Gerst pictures
"Probably a river in Kazakhstan or slightly west of it."—Alexander Gerst via Twitter on July 29, 2014Alexander Gerst—ESA/SIPA USA
An open history book of our planet: the #Sahara Desert
"An open history book of our planet: the #Sahara Desert"—Alexander Gerst via Twitter on July 26, 2014Alexander Gerst—ESA
Human-made fires in East Africa. Can you spot them?
"Human-made fires in East Africa. Can you spot them?"—Alexander Gerst via Twitter on July 9, 2014Alexander Gerst—ESA

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