Hubble revealed a universe of galaxies that existed beyond ours — but he couldn't have done it without a little help.

A hundred years ago, astronomer Edwin Hubble dramatically expanded the size of the known universe. At a meeting of the American Astronomical Society in January 1925, a paper read by one of his ...

Yet, a century ago, its discovery by Edwin Hubble opened humanity's eyes as to how large the universe really is, and revealed that our Milky Way galaxy is just one of hundreds of billions of ...