The Guardian reports today on new evidence suggesting that a previously-discovered impact zone in the Australian Outback is far larger than originally thought – making it the biggest impact zone yet known.
The impact was caused by an enormous meteorite that split into two 10km-wide chunks before it slammed into Earth around what is now the Warburton basin, lead researcher Andrew Glikson, from the Australian National University, said. "It would have been curtains for many life species on the planet at the time," he said.
Two huge bruises in the earth caused by the collisions were discovered 3km deep in the mantle and twin scars extending more than 190km long and 30km deep still mark the impact zone, which encompasses parts of Queensland, South Australia and the Northern Territory.
The easternmost scar was identified by chance in 2013 when geothermal drilling revealed traces of rocks that had been turned to glass by an extreme shock.
At present, it can't be implicated in any currently-known mass extinctions, meaning that the impact may predate all known mass extinction events.
Glikson said: "It's a mystery – we can't find an extinction event that matches these collisions. I have a suspicion the impact could be older than 300m years."
Read more: The Guardian