Large asteroid flying towards Earth and military try to destroy it and fail. 1 phrase I remember very good.
President is got that comet or asteroid is going to hit america and if they destroy it near orbit, it would break up and shower all over the planet and president says something like:
''Then America has to take a hit for the entire world''
Next scene - a journalist is reporting from emptied city saying ''we are having a last look at the cities before we say goodbye to them'' Journalist was female and wearing yellow coat.
Next scene - meteorite/comet hits with big flash. An old man and his grandsoon hide in the basement and it can be seen as whole house is blown away and then basement planks fly away.
Final scene - grandson runs away and needs to be rescured from a huge crater created by the hit.
I have rented out all movies i could find - about 3-4, but none of them matched what I saw here. I think it is one of those low budget TV Movies. May be SyFy