Blame the dinosaurs' extinction on a massive traffic accident in the asteroid belt.
That's the conclusion of a a joint Czech-American research team, which suggests in a new paper that the asteroid impact believed to be responsible for killing off the dinosaurs can be traced back to an 160 million-year-old collision between space rocks.
Combining observations of impacts on earth and the moon with new computer simulations, the team believes that a massive, 105-mile wide asteroid was hit by a 37-mile-wide neighbor, breaking it into tens or hundreds of thousands of pieces.
Over time, a small number of those pieces, many of them close to a mile in diameter, fell out of the asteroid belt's orbit. About 2 percent of the total material wound up hitting the Earth, the researchers believe, with a smaller amount striking the moon.
The evidence? A twofold surge in asteroid impacts on Earth and the moon, peaking about 100 million years ago, and "trailing off" today, researchers said.
The team estimates that the 111-mile-wide Chicxulub crater under
Mexico's Yucatan peninsula, which is widely believed to be related to the dinosaurs' demise, has a 90 percent probability of being from this group, called the Baptistina family. They say, with 70 percent certainty, that the moon's massive Tycho crater on the moon is also likely to be related.
Researchers say other asteroid smash-ups are likely to be related to significant events in the Earth's geological history. Says Southwest
Research Institute scientist William Bottke:
The study was published in the most recent issue of Nature.
(Image credit: SRI)
