Now, what would we (as in inhabitants of the planet Earth) do if there was a threatening asteroid on the collision course to earth? We’ve seen movies, read the books, but here’s a nice idea that I don’t believe I’ve seen before… using gravity as towline!
Let’s go over options one by one:
1) Nuking the thing to smaller pieces: can cause asteroid to brake-up to smaller, still threatening but this time less manageable pieces
2) Any type of solution which involves landing is dangerous
3) Placing thrusters on surface may be close to impossible – asteroids rotate, plus their composition may be such that it would simply brake up (see #1)
Using gravity will influence entire asteroid, no matter what composition it is, no landing is necessary, no nukes, just a big unmanned ship.