[ Maybe our “leaders” know we’re about to be wiped out so that’s why they don’t give a damn. They’re just going to enjoy the perks while they can. And they don’t tell us because they don’t want everyone upset and doing something to them just for fun. ]
I have often wondered about this very thing...
Sad thing is if true we could preserve humanity and work towards it, but the people in power would be too busy fighting for king of the hill instead of building the shelters needed for a chunk of the population...
They'd have to shut down too many large observatories, and access to the Hubble, and silence the astronomers. Amateur astronomers would eventually see such a large asteroid, anyway. A city-killer asteroid (150 feet dia.) could make it through undetected until it just before it hits.