doug141 writes "A scientist proposes the best way to deal with an asteroid on short notice is to hit it with an impactor, followed by a nuke in the crater. From the article: 'Bong Wie, director of the Asteroid Deflection Research Center at Iowa State University, described the system his team is developing to attendees at the International Space Development Conference in La Jolla, Calif., on May 23. The annual National Space Society gathering attracted hundreds from the space industry around the world. An anti-asteroid spacecraft would deliver a nuclear warhead to destroy an incoming threat before it could reach Earth, Wie said. The two-section spacecraft would consist of a kinetic energy impactor that would separate before arrival and blast a crater in the asteroid. The other half of the spacecraft would carry the nuclear weapon, which would then explode inside the crater after the vehicle impacted.'"