How to deal with an asteroid threat

MSNBC reports: "When it comes to 22-million-ton asteroids, the small stuff, it turns out, can make a huge difference in a potentially disastrous path toward Earth. Using limited observations and lots of high-end computer modeling, astronomers have gotten a better handle on the limitations of asteroid-track forecasting in a new study of a potentially threatening asteroid called Apophis. In this high-stakes game of Whack-a-Cosmic-Mole, just knowing exactly what it is you don't know can be useful."

We appear to be safe past 2029, the real worry is for now is 2036...