Scientist: Worry More About Asteroids

ByABC News
February 26, 2003, 2:14 PM

Feb. 27, 2003 -- Long ago David Morrison grew tired of the snickers he has heard for these many years. Despite the fact that he is a senior scientist with the NASA, some people regard him as a bit of a nut.

He's a prophet of doom in a three-piece suit.

Morrison has been shouting into the wind for a couple of decades now about a very real threat that many prefer to dismiss. He believes an asteroid or a comet may be headed our way and could smash into the Earth with catastrophic consequences, maybe even wiping out all life.

Yup, you've heard that so many times now that you want to chuckle. It's Star Wars stuff. And besides, there's probably little we can do about it anyway, so why waste time worrying?

Lesser Asteroids Also Pose Threats

But in the years since he first began to boldly proclaim that we need to take this threat seriously, Morrison has picked up support, and not just from astronomers who are cataloguing celestial bodies that we need to monitor closely. A small number of experts in various fields are joining the struggle, convinced that we shouldn't give up the battle before the fight is joined.

One of them is Lee Clarke, associate professor of sociology at Rutgers University and a specialist in disaster preparations. Clarke makes a point that is too often ignored.

We are focusing too much, Clarke maintains, on the "doomsday scenario." It would only take one of the approximately 700,000 mega-asteroids that are whipping around our solar system to wipe out all life on Earth. If one of them hits us, we're toast, and that is so unthinkable that it has turned many off to Morrison's lament.

Clarke calls that a "low-probability, high-consequence event," and it may not happen for thousands, or millions, of years. If at all.

What is far more likely, Clarke and others maintain, is a collision with a lesser asteroid or a comet that may not be a "planet killer," as he puts it, but quite capable of creating catastrophic results.

"That's a near-certain event with a range of consequences," he says, noting that a relatively small object, less than 200 feet in diameter, leveled trees over a 25-mile area in the Tunguska region of Siberia in 1908.