Edwin Powell HUBBLE
1924 - December 30 – Astronomer Edwin Hubble announces that Andromeda, previously believed to be a nebula, is actually another galaxy, and that the Milky Way is only one of many such galaxies in the universe

Edwin Hubble's discovery in 1924 revolutionized our understanding of the universe and our place within it. Before his findings, astronomers believed that the Milky Way was the extent of the universe, and that objects like the Andromeda "nebula" were part of our galaxy.

Hubble, using the newly constructed 100-inch Hooker telescope at Mount Wilson Observatory in California, was able to observe individual stars in the Andromeda "nebula." By studying these stars, he determined that Andromeda was much farther away than previously thought, and that it was, in fact, a separate galaxy similar to our own Milky Way.

This discovery fundamentally changed our view of the cosmos, suggesting that the universe was far larger and more complex than we had imagined. It also provided evidence for the expanding universe theory, which would later lead to the development of the Big Bang theory. Hubble's work laid the foundation for modern cosmology and earned him a lasting place in the annals of science.

December 30, 1924

Learn more about the life of      Edwin Powell HUBBLE.