There's another object near the left edge of the video, moving from top to bottom. Does anyone know what that is?
Its movement per frame seems too consistent and predictable to be an artifact (noise) of the camera.
Its movement per frame seems too consistent and predictable to be an artifact (noise) of the camera.
I made an image to show what I mean. See frames 4-7; it's not an exact match but maybe it's a clue: http://i.imgur.com/TADflVd.jpg
I hadn't considered the rotation, because as you point out, it doesn't exactly match up. It's gaining distance from the center of image as it moves.
It could still be some kind of internal reflection artifact (even dust?) which varies in distance slightly, I guess. I'm pretty sure the team looking at these images would have gone over every object in depth, so it's unlikely I've spotted something they haven't :)