Almost everything competing with Andromeda in that region of the sky is in the Milky May, and there's no problem differentiating between the two galaxies. In ot

Almost everything competing with Andromeda in that region of the sky is in the Milky May, and there's no problem differentiating between the two galaxies. In other words, galaxies are blurry but the Milky Way and Andromeda are sufficiently far apart that you can unambiguously partition 99.99999% of stars as being in one or the other.