Shoot out the trusters? there is no friction to stop the kinetic momentum in space.<p>Anyway you can rig the asteroid with explosives in the center of it, and just blow it to make a still dangerous giant meteor rain.<p>The rather hard sci-fi book series by Jack Campbell&#x2F;(non alias name is: John G. Hemry) by the name lost fleet is full of scenarious where planet dwellers are rather fucked against space forces.<p>Spoiler: Giant block of metal is all you need to do planetary bombardments from space, just send it off and Newton will do the rest. Good luck stopping the many many tons of a single metal object &quot;dropped&quot; from space.