Actually, as I mentioned in an earlier post, drilling would have worked just as well for the diversion plan, since exploding the nuke below the surface results in the bit above the explosion to work as reaction mass, making the nuke many times more effective for the course change.

Had they instead used a need to drill down far enough to make the reaction mass large enough for the needed course change, the movie could have been essentially the same, except for slightly different CGI, two lines of dialog, and having at least some part that was real physics.

__________________
‘To those who regard “crime fiction” as some sacred icon which must follow a rigid formula, I will always be the man who writes 18-syllable haiku.’Trying to make sense of computers, The Error Log.