Vector distribution of the proper motion of Blanco 1. The red dashed line in the figure marks the orientation (q_pm) of Blanco 1, while the blue dashed line marking the direction perpendicular to the orientation. Each gray dot represents its member star, and all gray arrows mark the proper motion vector of the members. All red arrows are the component vector of the proper motion along with the red dashed line, and all blue arrows represent the component vector along the blue dashed line. The length of all arrows represents the size of all vectors.