[weegee]

What is the FREQUENCY we are expecting some of these asteroids to come back? If we are talking hundreds of years, it is "good enough for government". The future generations will be able to do likewise, implement a better solution, already dead or enslaved, or have left the planet.

If we are only postponing disaster 10 years, then other more permanent solutions should be investigated.

[GregoryFul]

Once the orbit of an asteroid is determined it may be that a lot of options would be available. There are points in an orbit that are extremely sensitive to an external push. These Legandre points are balance points between influential gravitational bodies. Push a little bit at one of these points, and one can redirect enormously, the future path of the asteroid. Astronomical Ju-Jitsu.