Slamming into an astroid can have unpredictable results. It could shatter and send fragments in an unwanted direction. Better to send a rocket engine that can be turned on remotely, land it on the astroid, and turn it on at the right time to nudge the Asteroide to a safe path.
By the way, the spellings of astroid came from my speakwrite.
Or it could make the asteroid angry, come to Earth and ask “ alright. Who threw that?”