Yesterday in 1924, Edwin Hubble announced the discovery of other galaxies in the universe. Up to that point, it was believed that the Milky Way represented the entirety of the universe. How wrong we were. His discovery led to the eventual realization that there are at least 200 billion galaxies in the universe (and likely even more than that). The Webb Space Telescope (just launched on Christmas) will likely reveal even more about the breadth of the universe than we know now.