Here’s a much better illustration. There are many voids, just as there are many superclusters. They are one of the large scale structures in the universe.
Gravitational lensing can make a patch of space look like it has more stars than it does.
Are there arrangements of gravitational bodies that can create a black patch other than by direct absorption? Or would they necessarily have to have a halo of gravitational lensing around them, where the fields don’t interact as much?