Discovery of Andromeda Galaxy

Date: November 23, 1924 • Location: Rome, Italy

Edwin Hubble's discovery, that the Andromeda "nebula" is actually another island galaxy far outside our own Milky Way, is first published in The New York Times.

Edwin Powell Hubble was an American astronomer. He played a crucial role in establishing the fields of extragalactic astronomy and observational cosmology. Hubble proved that many objects previously thought to be clouds of dust and gas and classified as "nebulae" were actually galaxies beyond the Milky Way. He used the strong direct relationship between a classical Cepheid variable's luminosity and pulsation period for scaling galactic and extragalactic distances.