Armageddon - Extinction Events

Becker's team had previously found such gas-bearing buckyballs in rock layers associated with two known impact events: the 65 million-year-old Cretaceous-Tertiary impact and the 1.8 billion-year-old Sudbury impact crater in Ontario, Canada. They also found fullerenes containing similar gases in some meteorites. Taken together, these clues make a compelling case that a space rock struck the Earth at the time of the Great Dying.

But was an asteroid the killer, or merely an accomplice?

Many scientists believe that life was already struggling when the putative space rock arrived. Our planet was in the throes of severe volcanism. In a region that is now called Siberia, 1.5 million cubic kilometres of lava flowed from an awesome fissure in the crust. (For comparison, Mt. St. Helens unleashed about one cubic kilometre of lava in 1980.) Such an eruption would have scorched vast expanses of land, clouded the atmosphere with dust, and released climate-altering greenhouse gases.

World geography was also changing then. Plate tectonics pushed the continents together to form the super-continent Pangea and the super-ocean Panthalassa. Weather patterns and ocean currents shifted, many coastlines and their shallow marine ecosystems vanished, sea levels dropped.

Image Credit Chris Scotese. [more] What the world looked like 250 million years ago.

"If life suddenly has all these different things happen to it," Becker says, "and then you slam it with a rock the size of Mt. Everest - boy! That's just really bad luck."

Was the "crime" then merely an accident? Perhaps so. Nevertheless, it's wise to identify the suspects - an ongoing process - before it happens again...

For more information

Video: Armageddon [ Firstscience presents]
What are the chances of being hit by a killer asteriod? This film analyses all of the evidence, all of the odds, and predicts the day that the world will end.