Universe goes beyond the Milky Way galaxyĮdwin Hubble was born to Virginia Lee Hubble (née James) (1864–1934) and John Powell Hubble, an insurance executive, in Marshfield, Missouri, and moved to Wheaton, Illinois, in 1900.Hubble's name is most widely recognized for the Hubble Space Telescope, which was named in his honor, with a model prominently displayed in his hometown of Marshfield, Missouri. A decade before, the American astronomer Vesto Slipher had provided the first evidence that the light from many of these nebulae was strongly red-shifted, indicative of high recession velocities. The Hubble law implies that the universe is expanding. Hubble provided evidence that the recessional velocity of a galaxy increases with its distance from the Earth, a property now known as Hubble's law, although it had been proposed two years earlier by Georges Lemaître. He used the strong direct relationship between a classical Cepheid variable's luminosity and pulsation period (discovered in 1908 by Henrietta Swan Leavitt) for scaling galactic and extragalactic distances. 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 played a crucial role in establishing the fields of extragalactic astronomy and observational cosmology. The SAO/NASA Astrophysics Data System.Ultimate fate of the universe Early universeĮdwin Powell Hubble (Novem– September 28, 1953) was an American astronomer. Monthly Notices of the Royal Astronomical Society, 97, p513. ↑ Red-shifts and the distribution of nebulae, Hubble, Edwin 1937.↑ Effects of red shifts on the distribution of nebulae, Hubble, Edwin 1937.Edwin Hubble 1889–1953, The Journal of the Royal Astronomical Society of Canada, Vol. 'Slipher's redshifts as support for de Sitter's model and the discovery of the dynamic universe' In Origins of the Expanding Universe: 1912–1932. "Lost in translation: Mystery of the missing text solved". ↑ Eugenie Samuel Reich Published online 27 June 2011| Nature| doi: 10.1038/news.2011.385.
"… if redshifts are velocity shifts which measure the rate of expansion, the expanding models are definitely inconsistent with the observations that have been made … expanding models are a forced interpretation of the observational results" Hubble himself did not see his 1929 data as evidence for an expanding Universe. This discovery lead to the notion of the expanding universe which is the centre-piece of the cosmology of the present day. The linear velocity-distance relation was established.The distribution of galaxies was found to be homogeneous in distance (the galaxies were all over the universe, not in any particular location).Hubble settled decisively the question of the nature of the galaxies (as being other things like the Milky Way).A classification system for nebulae, both galactic (diffuse) and extragalactic (both nebulae inside our Milky Way galaxy, and other galaxies outside it).The Hubble Space Telescope was named after Hubble.įour major achievements Īccording to Sandage, Hubble achieved four main things:
Some have incorrectly said that Hubble discovered the Doppler shift in the spectra of galaxies, but this had already been observed earlier by Vesto Slipher, whose data Hubble used. This work helped to establish that the universe is expanding. Light traveling through stretching space experiences a Hubble-type redshift. Today, the 'apparent velocities' of galaxies are understood as an increase in proper distance which occurs due to the expansion of space. Nevertheless, the idea bears Hubble's name to this day. Georges Lemaître, a Belgian priest and astronomer, had published the idea two years before in an obscure journal. The law states that the greater the distance between any two galaxies, the greater their relative speed of separation. In 1929 Hubble formulated what is called Hubble's law. Redshift is observed in the light spectrum Doppler effect is the change in pitch or colour when an object or sound comes in (higher pitch, brighter color) or moves away (lower and darker). Hubble found the degree of Doppler effect ( redshift) from a galaxy increased in proportion to its distance from Earth. Then he proved the galaxies were moving away from each other.
Also, he developed a method for classifying galaxies. In 1925 he showed that there are galaxies beyond our own, the Milky Way. Hubble's findings changed the scientific view of the universe. Wavelength increases up towards the red and beyond (frequency decreases).Įdwin Powell Hubble (November 20, 1889 – September 28, 1953) was an American astronomer.
Absorption lines in the optical spectrum of a supercluster of distant galaxies (right), as compared to absorption lines in the optical spectrum of the Sun (left).
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