“Making it a giant kinetic bomb, should it strike land.”
Or it could be a large cannon ball it it hits the ocean! (71% of earths surface)
It wont work like that. A kinetic weapon has to enter steeply and aerodynamically and reach impact before atmospheric air resistance slows it to a sedate terminal velocity.
This thing is going to brush the upper atmosphere several times and then take a very long lazy arc to the surface. It may really wreck anytthing it hits but its not going to hit like a “rod from god” weapon.