I orginally posted this as a poll idea in the
Astronomy Related Polls - Ideas??? thread, but I got anxious to get it out here as a real poll for a bit of fun. Maybe it should be in Chit Chat, but on the other hand, it is really astronomy related.
In any case, I think each one of these scenarious would serve to at least bring significant positive attention to astronomy if not blatently demonstrating the possible threats to Earth that so many people just don't even think about at all. I personally favor the meteor impact to have the greatest affect world wide, even though it's a potentially deadly one but not necessarily a catostrophic one.
So, I'm throwing out the ball here to see what others think.