All you need is a tiny perturbation from far enough out to deviate the comet/asteroid, and if you change its spin + the radiation blast front that should in principle be enough.
You would want to blast a neutron bomb or something of that nature for the maximum directed throughput as well as a direct impact nuke.
But again, maybe im missing something obvious here. Lets say you split an extinction lvl event asteroid into two large inhomogenous pieces from far enough. These two pieces will now in their frame more or less only feel their own gravitational effects. This in principle could convert the objects net momentum after the blast into some small angular momentum piece.
Now, an inhomogenous object(s) that have interacting angular components will add tiny vector components to its net orbit assuming you aren't in a complete vacuum. Since you in principle have a years worth of time for such tiny perturbations to become significant, it strikes me that we aren't that far off from being enough to deviate it.
You would want to blast a neutron bomb or something of that nature for the maximum directed throughput as well as a direct impact nuke.
But again, maybe im missing something obvious here. Lets say you split an extinction lvl event asteroid into two large inhomogenous pieces from far enough. These two pieces will now in their frame more or less only feel their own gravitational effects. This in principle could convert the objects net momentum after the blast into some small angular momentum piece.
Now, an inhomogenous object(s) that have interacting angular components will add tiny vector components to its net orbit assuming you aren't in a complete vacuum. Since you in principle have a years worth of time for such tiny perturbations to become significant, it strikes me that we aren't that far off from being enough to deviate it.