Australian Glass Beads

Australian scientists have found evidence of a huge asteroid they say slammed into Earth some 3.46 billion years ago -- making it the second oldest known to have hit the planet and larger than the one blamed for wiping out the dinosaurs.

Australian scientists have found evidence of a huge asteroid they say slammed into Earth some 3.46 billion years ago -- making it the second oldest known to have hit the planet and larger than the one blamed for wiping out the dinosaurs.