[guason]

Does this look like impact damage?

I was driving along and heard a crack. There was a car maybe approx 200m in front of me in the left lane.

Really bad luck I suppose?

Imgur: The magic of the Internet

[Dazzler]

Yep, looks like impact damage to me. You weren't going under an overpass or anything like that? Unlucky for sure! 

[mickd]

Yep . Check your insurance -you may have "excess free window " in it.