The movie ends with a white out, which represents the Big Bang or creation of the Universe. Following that, the white areas behind the credits condense, which correlates with the condensation of matter and ultimate large scale structure of the universe. These devolve to a black screen, the early "opaque" stage of the universe, when early particles were forming. From this, stars begin to form, one by one until the credits end with a universe full of stars and the story of our universe to the present, told behind the credits.
The entire credits run against a star field background, then at the very, very end there is one final sigh as they fade to black.