In 1920, astronomers Harlow Shapley and Heber Curtis held a Great Debate. Shapley argued that the spiral nebulae were small and in the Milky Way, while Curtis took a more radical position that they ...

Curtis argued that the spiral nebulas were galaxies in their own right, but said that the Milky Way was only 10,000 light years across. Shapley argued the opposite. Hubble enters the fray Edwin ...

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 ...

Around 13.7 billion years ago, something collapsed. It fell outward into the nothingness that stretched in every direction, ...

A century ago, Edwin Hubble revealed that the "spiral nebula" was not part of our Milky Way but located 2.5 million light-years away, about 25 times the Milky Way's diameter. Before this discovery ...

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.