Color composite image of the dual quasar J0749+2255 at z ≈ 2.17, created from observations obtained with HST/WFC3’s F475W (green) and F814W (red) filters. Superimposed are two small circles (#0, #1) centered on the quasar cores and two offset regions (#2, #3) from these cores. The larger ellipse contains the central brightest region (see Figure 2(b)). Each of the small circles has an aperture size of 1.7 kpc, while the size of the large ellipse is 3.7 kpc × 5.0 kpc.