It was interesting seeing the voyage of this space rock. I felt I was in the mind of the comet--felt what it felt. Passing all other planets, the comet feels kin to Earth, an irresistible signal, and then dives in. Again, as it plummets, the reader feels as if they are the comet, crashing down upon the countryside.
Then you lose that POV and switch over to the citizens and the Nasa officials. A great last line, typical of our government, but you did change POV.