What is after Space and the Galaxy?

How do you define (or observe) TOTAL "space"? We can only make observations based on what we see, and make educated guesses about what we haven't seen yet.

Even though there is a lot of space between a galaxy's star systems and the bodies that make up its solar system, there are still traces of matter and/or energy to be found in between.

We cannot "know" what is beyond our limited view. Does the universe of galaxies exist forever? Is there an even bigger, incomprehensible gap between this universe and another one, or more? We only know that there are many galaxies and that they are separated by even greater distances.

One reason we are still exploring is that we do not know!

After the galaxy, the next largest structure in the universe is the galaxy cluster. Galaxy clusters are groups of galaxies held together by gravity. Beyond galaxy clusters, there are superclusters, which are large groupings of galaxy clusters. The universe is structured in a hierarchical manner, with smaller structures like stars, planets, and moons within galaxies, which in turn are part of larger structures like galaxy clusters and superclusters.