Crazy Circle Illusion

My version of an animation that has been created and recreated many times on the internet. I first saw it as "Crazy Circle Illusion" on Brusspup's YouTube channel. Press Play. What do you observe? You're likely to say something like, "A circle rolling inside a larger circle." But how else could you interpret what you see? Maybe a polygon rolling inside a circle? Or if it's a polygon, must the points represent the vertices of the polygon? Could they be lateral midpoints or some other points of the polygon? Any other interpretations? What else do you notice about the geometry in this animation? Check the Highlight one point box, and then make on observation about that point. Check the Show additional geometry box to see if it affirms your observation.