Image frame obtained by NHAO 60 cm telescope/POL. The four subframes correspond to images at four polarization position angles: from the left subframe to the right, 45°, 135°, 90°, and 0° as measured counterclockwise with respect to equatorial north. The POL views a single field. The FOV of a single subframe is |$\sim \! {2{^{\prime}_{.}}2} \times 7^{\prime }$|⁠. North is up, and east is left.