EXPLORE: The Big Bang
1 Edwin Hubble
One of the astronomers who's observations contributed to the theory of the Big Bang was Edwin Hubble. He discovered He used the 100-inch reflecting telescope at the Mount Wilson Observatory in California to show that some distant specks of light seen through telescopes are actually other galaxies. He also measured these distances to hundreds of galaxies, and discovered that the universe is expanding. His data would eventually show us how the universe is changing, and even give us clues as to how the universe formed.
Hubble combined his measurements of the distances to galaxies with other astronomers' measurements about redshift (the movement of stars and galaxies away from us). He noticed a relationship, which is now called Hubble's Law. Hubble's law states: