In this movie, we zoom in on one galaxy and watch as it is formed. The panel on the left shows how hydrogen gas, the fuel from which stars form, is pulled together in a swirling mass. Early in the history of the universe, the galaxy is chaotic and forming in many fragments. As time passes, a single swirling spiral of gas forms, very similar to our own galaxy. The panel on the right shows how the heavy elements (the material from which planets are made) build up and are spread through-out the cosmos.