Rotational velocity (degree per minute) in function of the time for the Eastern + Africa array movie (left) and for the Western array movie (right). In green, the rotational velocity for the hotspot movie simulation. The profile were obtained by searching for the angle that maximize the similarity between each frame and the subsequent fifth frame. The Eastern array + Africa movie presents a more robust reconstruction of the hotspot rotation than the Western array. The negative values of the rotation are artifacts produced by the method utilized.