Yet USC sunk deeper and deeper into the quicksand of its own arrogance, until it realized that all it had accomplished had only come about because of broken rules and scorched earth.

FORBES: USC's Fall From College Sports Elite A Cautionary Tale

One answer might be that the two impacts were, in effect, simultaneous that the objects which created Shiva and Chicxulub were the daughters of a comet that had broken up in space and hit the Earth a few hours apart, as the pieces of comet Shoemaker-Levy 9 hit Jupiter in 1994.

ECONOMIST: Mass extinctions