Edwin Hubble (November 20, 1889 – September 28, 1953) was an American astronomer who profoundly changed the understanding of the universe by confirming the existence of galaxies other than the Milky Way. He also considered the idea that the loss in frequency—the redshift—observed in the spectra of light from other galaxies increased in proportion to a particular galaxy's distance from Earth. This relationship became known as Hubble's law.
Georges Henri Joseph Édouard Lemaître (French: [ʒɔʁʒə ləmɛtʁ] ( listen); 17 July 1894 – 20 June 1966) was a Belgian priest, astronomer and professor of physics at the Catholic University of Leuven. He proposed the theory of the expansion of the universe, widely misattributed to Edwin Hubble.