20 November 17

Edwin Hubble was born on this date in 1889. The Hubble Space Telescope is named to honor this man who is credited with discovering the first star and galaxy outside the Milky Way. In 1923, while working at the Mount Wilson Observatory, Hubble discerned discrete stars in the fuzzy areas that were thought to be clouds of dust and gas and had been labeled "nebulae." Hubble's conclusion that nebulae were actually far distant galaxies became accepted by the end of the 1920s. In 1929, Hubble proved that all of the galaxies were moving apart -- or, in other words, that the entire universe is expanding. Today I am astounded to realize that our knowledge of "other galaxies" is less than 100 years old. My tie shows a variety of planets and galaxies!