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

In the 1920s, astronomers thought that the Milky Way was the entire universe. Hubble's discovery revealed a much bigger ...

Edwin Hubble was young and ambitious ... His measurements marked the end of the Great Debate about the Milky Way's size and the nature of the nebulae. Hubble wrote about his discovery to Harlow ...

Edwin Hubble was young and ambitious ... His measurements marked the end of the Great Debate about the Milky Way's size and the nature of the nebulae. Hubble wrote about his discovery to Harlow ...

Hubble makes his mark Edwin Hubble was young and ambitious ... His measurements marked the end of the Great Debate about the Milky Way’s size and the nature of the nebulae.