This Is a Galaxy

Ideally, science works by the testing of hypotheses. In the real world, however, hypotheses can't always be tested directly, so scientists have to get creative and figure out indirect ways to see whether hypotheses are at least consistent with our empirical observations. Consistency alone is not sufficient for thinking that a scientific hypothesis is 'correct,' but inconsistency is usually a safe red flag that the hypothesis in question either needs modification or ought to be rejected.

One such attempt to test scientific hypotheses indirectly is to create computer models and simulations based on the very best current knowledge available: you let the simulations run and then see how close a match they make to what we know about the world.

There are many benefits to such an approach, such as the reduced time it takes to run a simulation (as opposed to waiting for the universe to run on its own slow pace). Another is the fact that when you produce visual representations of a computer simulation, you can end up with a beautiful piece of art, as the following short clip demonstrates:

And for more, check out the space tag.