It looks just like an airborne missile: http://www.youtube.com/watch?v=VrC9qEFtjPE edit: fast forward to the 48 second mark.
very cool, if that was a missile flying that close to a civilian plane i dont think ill ever fly again
by definition it is an Unidentified Flying Object..emphasis on unidentified.. don't think it is a ufo..if i had to guess i would agree with the missile thing, but there just is not enough info to identify it..
Watching it in slomo it literally looks like its going so fast its breaking through the air. Idk how to explain what I mean. But it sure does leave that airplane in the dust.