remind me of how much asteroid was left after the Tunguska eventWhy making things complicate? De-orbit slightly a NEO asteroid between the Earth and the Sun so that it takes the path towards Venus (not much thrust needed for that), 'aereobrake' it in Venus' atmosphere such that inserts itself into a synchronous orbit with the Earth + a component for Venus-Earth orbit transferal, and then, once it reaches Earth (at zero orbital velocity) let the thing simply fall freely and splash somewhere in a safe place in the ocean. It would be something like a Tunguska event, but at thousands of miles away from any inhabitated region. Maybe there is a problem with a Tsunami wave, but I think that if the asteroid is not too big, it will not harm. So, why not?