12/12/2012: Planet killer visits Earth

NASA pegged asteroid 4179 Toutatis' closest approach to Earth today at "18 times farther than the moon." Toutatis passes by the Earth every four years. At 3 miles across, it is comparable in size to the asteroid that most scientists believe killed the dinosaurs and about two-thirds of the other species on the planet 60 million years ago. /NASA image


An odd coincidence?

Tons of ink have been spilled and megabytes of server space consumed over the 12/21/2012 prediction of doom in the Mayan calendar. Given the Mayans' sophisticated understanding of astronomy, could they have predicted for today a devastating collision of asteroid 4179 Toutatis and Earth?

Mayan math may have been off a few million miles, but the potential for a cataclysmic asteroid strike on Earth deserves more attention than it gets. Ironically, as various and sundry prognostications of Armageddon spark periodic media frenzies, the search for killer asteroids, from city busters to planet-scorching mountains of spaceborne rock and ice, goes on in the darkness outside the media spotlight.

Understanding the impact of asteroids on the evolution of Earth is a relatively fresh area of science. Speculation over the cause of the Moon's craters raged well into the middle of the 20th century, when geologist Gene Shoemaker solved the mystery at Meteor Crater in Arizona. In the 1950s, Shoemaker proved that the mile-wide, 550-feet-deep gash in the Arizona desert was the result of a meteor strike about 50,000 years ago. Subsequent research, including the Apollo missions to the Moon's surface, proved asteroid strikes have been a feature of planetary evolution in our solar system for billions of years.

Scientists are now studying the possible role of asteroids bringing water and even life to Earth. Where there's life, there's death, and killer asteroids can apparently generate a lot of death.