I've come up with this question as I've read about an Asteroid named Apophis (it's full name is "9994 Apophis" and is named after the Greek word for Apep - the Egyptian Deity who embodies Chaos). For a long time, it was believed that the Asteroid may collide with Earth, although NASA now states it will fly by closely with no impact: jpl.nasa.gov/news/news.php?feature=7390
However, if Earth faced an undeniable incoming asteroid - with a size comparable to the asteroid that caused the extinction of the dinosaurs - then how would the Wizarding World deal with it, especially if the attempts of Muggles to divert/destroy it fail?
I personally doubt this is an instance where they would just sit back with a pint of butterbeer and wait for everything to blow over, especially when you consider the effects the asteroid impact had.
So how do you think the Wizards would deal with such a catastrophic 'missile' hurtling towards Earth - one that could end human life as we know it?
To get an idea of how devastating such an impact would be, check out 22:38 to 26:50 of this video: