Any idea what the colors indicate. There are some patches of mainly blue galaxies on a black background. These stand out as kind of unique. I initially zoomed a

Any idea what the colors indicate. There are some patches of mainly blue galaxies on a black background. These stand out as kind of unique. I initially zoomed all the way out, and in the top left is a giant blue and black area that looks like a lamp. I assumed this to be some imaging problem. Upon zooming in though one can see other blue on black areas.