Portrait of Edwin Hubble

Edwin Hubble

American astronomer

Lived
1889–1953

Updated September 2026

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About Edwin Hubble

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.

Biography from Wikipedia, CC BY-SA 4.0. Photo via Wikimedia Commons.

Sources: book lists and dates from Wikidata and Open Library, ratings from Open Library readers, free texts from Project Gutenberg. Last updated September 2026.