This illustration shows American astronomer Edwin Hubble (1889-1953) on the right and Belgian priest and cosmologist Georges Lemaître (1894-1966) on the left. Based on new evidence, both scientists should share credit for independently uncovering evidence for the expanding universe in the late 1920s. Lemaître is also credited with proposing a theory for the origin of the universe that would later be called the "big bang." The telescope on the left is the 100-inch Hooker Telescope on Mt. Wilson in California. The Hubble Space Telescope is on the right.