Dinosaur-killing asteroid triggered global tsunami that scoured seafloor thousands of miles from impact site
miles-wide asteroid that struck Earth 66 million years ago wiped out nearly all the dinosaurs and roughly three-quarters of the planet's plant and animal species.
up to 30,000 times larger than the energy in the December 2004 Indian Ocean earthquake tsunami, which killed more than 230,000 people
a 4.5-kilometer-high (2.8-mile-high) wave that subsided as the ejecta fell back to Earth.