Killer Asteroids May Escape NASA's Notice

NASA is charged with seeking out nearly all the asteroids that threaten Earth

but doesn't have the money to do the job, a federal report says.

That's because even though Congress assigned the space agency this mission four years ago, it never gave NASA money to build the necessary telescopes, the new National Academy of Sciences report says.

Specifically, NASA has been ordered to spot 90 percent of the potentially deadly rocks hurtling through space by 2020.

Even so, NASA says it's completed about one-third of its assignment with its current telescope system.

NASA estimates that there are about 20,000 asteroids and comets in our solar system that are potential threats to Earth. They are larger than 460 feet in diameter -- slightly smaller than the Superdome in New Orleans. So far, scientists know where about 6,000 of these objects are.

Rocks between 460 feet and 3,280 feet in diameter can devastate an entire region but not the entire globe, said Lindley Johnson, NASA's manager of the near-Earth objects program. Objects bigger than that are even more threatening, of course.

http://parasearcher.blogspot.com/2009/08/apocalypse-watch-killer-asteroids-may.html

Just give each one a set of binoculars and a sector of sky to watch. That might actually make them useful.

get you.

If we can estimate where it will hit, we can evacuate, shelter, and prepare medical facilities etc for disaster recovery.
If we can't estimate where it will hit, 2/3 of the earths surface is water, and half the population lives within 50 miles of the coast, so evacuating the coastlines could save a lot of lives.
If it's a planet-killer, then we could do all those things we normally wouldn't risk doing.

We might find some that we could actually cause to miss Earth. A small "shove" has a much bigger effect the longer in advance of potential impact one can impart that shove, and a good survey is critical both to assessing the near-term risks and assessing developing responses beyond the measures bananas lists.