The thing about this is that the impact might be visible from earth across most of the US, and to the naked eye.
You're the second person on FR that has told me that. The article I read didn't mention that but, said it would be visible through telescopes. There will be a number of serious 'scopes' on it though...The Hubble, Chandra and etc. will be viewing/recording the impact. We'll get some very good pictures. The article I read said that images of the incident would be on the internet 15 minutes after impact.