See: http://neo.jpl.nasa.gov/ A sub part of this site was mentioned in the article that you posted Friday, but I’d recommend posting this main page of the site.
People forget we had an asteroid pass very close to us last year, just 2/3 the distance to the moon. (Called a lunar distance or "LD").
Let’s look at two more things. 1.) NASA just recently proved they can hit an asteroid with a satellite. Doesn’t that strike you as at least a little odd they would spend the money to do that just for researching the impact? 2.) Now, did you also notice that the military is working on a new type of “bunker busting” nuclear penetration bomb that survives for 100 milliseconds, burrowing into the ground through concrete and steel, and then goes off? Put the two together and you have a far more realistic approach to busting an approaching asteroid than was portrayed in the movies Deep Impact or Armageddon. - Rourke