Antarctica's Tunguska Event

Giant, extinction-sized asteroids hurtling into Earth may grab headlines and star in Hollywood blockbusters, but airbursts from smaller asteroids and comets are thought to occur once every 500-1,000 years, making them one of the most pressing threats to humanity from space. That makes the discovery of an Antarctic airburst -- a sort of austral Tunguska [...]

March 5, 2010
2:19 PM EST