1: The devastating event took place on our planet many millions of years ago , but researchers are only now beginning to discover what happened . 2: In a remote part of Central Australia , the two pieces of asteroid left what geophysicists say is the largest impact zone ever found on Earth , spreading over an area 400 kilometers ( 250 miles ) wide . 3: Two pieces of asteroid crashed into Australia many millions of years ago .
1: The devastating event 2: the two pieces of asteroid 3: asteroid