[aptsurdist]

One of the most fascinating aspects of the video is that the thing rotates.

As others have noted, the camera is auto-centering the object. If you look at the object's movement relative to the clouds in the background, it seems that the object might be turning and exposing its broader side to the relative direction of travel as seen from the camera. And then slowing down in the plane as viewed from the camera.

Note, this movement is relative and it's very hard to get a sense of perspective. So rather than slowing down, this could be the object banking and changing direction to move towards or away from the camera?

Maybe it's just a foreign aircraft with some kind of wingless shape like the B-2 bomber? I can't find a good source, but it seems there are blogs talking about new foreign stealth drones that could look like this. (http://defence-blog.com/news/new-stealth-bomber-spotted-in-c... -- not sure if this source is legit)

P.S. This is all assuming that this is indeed some kind of flying thing and not some kind of mirage.