- Edwin Hubble
name = Edwin Hubble|
birth_date = birth date|1889|11|20|mf=y
birth_place = Marshfield,
residence = U.S.
nationality = American
death_date = death date and age|1953|9|28|1889|11|20|mf=y
death_place = San Marino,
University of Chicago Mount Wilson Observatory
University of Chicago Oxford University
Big Bang Hubble's law Redshift Hubble sequence
Edwin Powell Hubble (
November 20, 1889– September 28, 1953) was an American astronomer. He profoundly changed astronomers' understanding of the nature of the universe by demonstrating the existence of other galaxies besides the Milky Way. He also discovered that the degree of redshift observed in light coming from a galaxy increased in proportion to the distance of that galaxy from the Milky Way. This became known as Hubble's law, and would help establish that the universe is expanding.
He was born to an insurance executive in
Marshfield, Missouriand moved to Wheaton, Illinoisin 1889. In his younger days he was noted more for his athletic prowess than his intellectual abilities, although he did earn good grades in every subject except for spelling. He won seven first places and a third place in a single high school track meet in 1906. That year he also set a state record for high jumpin Illinois.
His studies at the
University of Chicagoconcentrated on mathematics, astronomy, and philosophy which led to a BS degree in 1910. Hubble also became a member of the Kappa Sigma Fraternityand in 1948 was named Kappa Sigma "Man of the Year". He spent the next three years as one of Oxford's first Rhodes Scholars, where he originally studied jurisprudence, before switching his major to Spanish and receiving the MA degree, after which he returned to the United States. Some of his British mannerisms and dress stayed with him all his life, occasionally irritating his American colleagues.
Returning to the United States he worked as a
high schoolteacher and a basketballcoach at New Albany High School in New Albany, Indiana(near Louisville, Kentucky), and was a member of the Kentucky bar, although he reportedly never actually practiced law in Kentucky. [ [http://www.aip.org/history/cosmology/ideas/hubble.htm Who Was Edwin Hubble?] ] He served in World War Iand quickly advanced to the rank of major. He returned to astronomy at the Yerkes Observatoryof the University of Chicago, where he earned a PhD in 1917 with a dissertation entitled [http://www.archive.org/details/photographicinve00hubbrich Photographic Investigations of Faint Nebulae] .
In 1919 Hubble was offered a staff position by
George Ellery Hale, the founder and director of Carnegie Institution's Mount Wilson Observatory, near Pasadena, California, where he remained until his death. He also served in the US Army at the Aberdeen Proving Groundduring World War II. For his work there he received the Legion of Merit. Shortly before his death, Palomar's 200-inch Hale Telescopewas completed; Hubble was the first to use it. Hubble continued his researches at the Mount Wilson and Palomar Observatories, where he remained active until his death.
Hubble died of a
cerebral thrombosison September 28, 1953, in San Marino, California. No funeral was held and his wife, Grace, did not reveal what happened to his body. [ A Short History of Nearly Everything, Bill Bryson]
The Universe goes beyond the Milky Way galaxy
Hubble's arrival at Mount Wilson in 1919 coincided roughly with the completion of the 100-inch Hooker Telescope, then the world's largest telescope. At that time, the prevailing view of the cosmos was that the universe consisted entirely of the
Milky Way. Using the Hooker Telescope, Hubble identified Cepheid variables(a kind of star; see also standard candle) in several spiral nebulae, including the Andromeda Galaxy. His observations, made in 1922–1923, proved conclusively that these nebulae were much too distant to be part of the Milky Way and were, in fact, entire galaxies outside our own. This idea had been opposed by many in the astronomy establishment of the time, in particular by Harvard-based Harlow Shapley. Hubble's discovery, announced on January 1, 1925, fundamentally changed the view of the universe.
Hubble also devised the most commonly used system for classifying galaxies, grouping them according to their appearance in
photographicimages. He arranged the different groups of galaxies in what became known as the Hubble sequence.
Redshift increases with distance
Hubble was generally incorrectly credited with discovering [This had actually been observed by
Vesto Slipherin the 1910s, but the world was largely unaware. Ref: Slipher (1917): Proc. Amer. Phil. Soc., 56, 403.] the redshiftof galaxies. These measurements and their significance were understood before 1918 by James Edward Keeler(Lick & Allegheny), Vesto Melvin Slipher(Lowell), and Professor William Wallace Campbell(Lick) at other observatories. Combining his own measurements of galaxy distances with Vesto Slipher's measurements of the redshifts associated with the galaxies, Hubble and Milton L. Humasondiscovered a rough proportionality of the objects' distances with their redshifts. Though there was considerable scatter (now known to be due to peculiar velocities), Hubble and Humason were able to plot a trend line from the 46 galaxies they studied and obtained a value for the Hubble-Humason constant of 500 km/s/Mpc, which is much higher than the currently accepted value due to errors in their distance calibrations. [Distance determination in astronomy continues to be an active area of research, see the article on cosmic distance ladderfor more details.] In 1929 Hubble and Humason formulated the empirical Redshift Distance Law of galaxies, nowadays termed simply Hubble's law, which, if the redshift is interpreted as a measure of recession speed, is consistent with the solutions of Einstein’s equations of general relativity for a homogeneous, isotropic expanding space. Although concepts underlying an expanding universewere well understood earlier, this statement by Hubble and Humason led to wider scale acceptance for this view. The law states that the greater the distance between any two galaxies, the greater their relative speed of separation.
This discovery was the first observational support for the
Big Bangtheory which had been proposed by Alexander Friedmannin 1922. The observed velocities of distant galaxies, taken together with the cosmological principleappeared to show that the Universe was expanding in a manner consistent with the Friedmann-Lemaître model of general relativity. In 1931 Hubble wrote a letter to the Dutch cosmologist Willem De Sitterexpressing his opinion on the theoretical interpretation of the redshift-distance relation: [ [http://www.astronomycafe.net/anthol/expan.html Galaxy redshifts reconsidered - The Astronomy Cafe, Dr. Sten Odenwald ] ] : "... we use the term 'apparent velocities' in order to emphasize the empirical feature of the correlation. The interpretation, we feel, should be left to you and the very few others who are competent to discuss the matter with authority."Today, the 'apparent velocities' in question are considered to be artifacts of a coordinate transformationthat occurs in an expanding space. Light traveling through stretching space will experience a Hubble-type redshift, a mechanism different from the Doppler effect.
In the 1930s Hubble was involved in determining the distribution of galaxies and spatial curvature. These data seemed to indicate that the universe was flat and homogeneous, but there was a deviation from flatness at large redshifts. According to
Allan Sandage, : "Hubble believed that his count data gave a more reasonable result concerning spatial curvature if the redshift correction was made assuming no recession. To the very end of his writings he maintained this position, favouring (or at the very least keeping open) the model where no true expansion exists, and therefore that the redshift "represents a hitherto unrecognized principle of nature." [ [http://antwrp.gsfc.nasa.gov/diamond_jubilee/1996/sandage_hubble.html EDWIN HUBBLE 1889-1953 By Allan Sandage (1989, JRASC Vol. 83, No.6) ] ] There were methodological problems with Hubble's survey technique that showed a deviation from flatness at large redshifts. In particular the technique did not account for changes in luminosity of galaxies due to galaxy evolution.
Earlier, in 1917,
Albert Einsteinhad found that his newly developed theory of general relativity indicated that the universe must be either expanding or contracting. Unable to believe what his own equations were telling him, Einstein introduced a cosmological constant(a "fudge factor") to the equations to avoid this "problem". When Einstein heard of Hubble's discovery, he said that changing his equations was "the biggest blunder of [his] life". [ [http://www.pbs.org/wnet/hawking/strange/html/strange_cosmo.html Cosmological Constant from "Stephen Hawking's Universe" on PBS ] ]
Hubble discovered the
asteroid 1373 Cincinnation August 30, 1935. He also wrote "The Observational Approach to Cosmology" and "The Realm of the Nebulae" around this time.
Hubble spent much of the later part of his career attempting to have astronomy considered an area of physics, instead of being its own science. He did this largely so that astronomers - including himself - could be recognized by the
Nobel PrizeCommittee for their valuable contributions to astrophysics. This campaign was unsuccessful in Hubble's lifetime, but shortly after his death the Nobel Prize Committee decided that astronomical work would be eligible for the physics prize. [ [http://astroprofspage.com/archives/450 Astroprof's article on Hubble] ]
On March 6, 2008, the United States Postal Service released a 41 cent stamp honoring Hubble on a sheet titled "American Scientists." His citation reads: 'Often called a "pioneer of the distant stars," astronomer Edwin Hubble (1889-1953) played a pivotal role in deciphering the vast and complex nature of the universe. His meticulous studies of spiral nebulae proved the existence of galaxies other than our own Milky Way. Had he not died suddenly in 1953, Hubble would have won that year's Nobel Prize in Physics.' The other scientists on the "American Scientists" sheet include
Gerty Cori, biochemist; Linus Pauling, chemist; and John Bardeen, physicist.
Bruce Medalin 1938.
Gold Medal of the Royal Astronomical Societyin 1940.
Medal of Meritfor outstanding contribution to ballisticsresearch in 1946.Named after him
Asteroid 2069 Hubble.
* Hubble crater on the
Hubble Space Telescope.
* Edwin P. Hubble
Planetarium, located in the Edward R. MurrowHigh School, Brooklyn, NY.
* Edwin Hubble Highway, the stretch of
Interstate 44passing through his birthplace of Marshfield, Missouri
* The "Edwin P. Hubble Medal of Initiative" is awarded annually by the city of
Marshfield, Missouri- Hubble's birthplace
Hubble Middle Schoolin Wheaton, Illinois—renamed for Edwin Hubble when Wheaton Central High School was converted to a middle school in the fall of 1992.
* 2008 "American Scientists" US stamp series, $0.41
*Christianson, Gale; "Edwin Hubble: Mariner of the Nebulae" Farrar Straus & Giroux (T) (New York, August 1995.)
*Hubble E.P., "The Observational Approach to Cosmology" (Oxford, 1937.)
*Hubble E.P., "The Realm of the Nebulae" (New Haven, 1936.)
*cite journal |last=Hubble |first=Edwin |authorlink= |coauthors= |year=1929 |month= |title=A relation between distance and radial velocity among extra-galactic nebulae |journal=PNAS |volume=15 |issue=3 |pages=168–173 |id= |url=http://www.pnas.org/cgi/reprint/15/3/168 |accessdate= |quote=|doi=10.1073/pnas.15.3.168
* [http://antwrp.gsfc.nasa.gov/diamond_jubilee/d_1996/hubble_nas.html BIOGRAPHICAL MEMOIRS NAS 41 by N.U. Mayall]
Galaxy morphological classification
Gerard de Vaucouleurs
De Vaucouleurs modified Hubble sequence
William Wilson Morgan
Expansion of the universe
Hubble Space Telescope
Cosmic distance ladder
Edwin Hubble House, residence and National Historic Landmarkin San Marino, California
* [http://www.time.com/time/time100/scientist/profile/hubble.html Time 100 Profile]
* [http://www.astro.louisville.edu/education/hubble_in_louisville/nahs/ Astronomy at the University of Louisville] - Photographs of Edwin Hubble at New Albany High School.
* [http://antwrp.gsfc.nasa.gov/diamond_jubilee/1996/sandage_hubble.html Edwin Hubble bio] - Written by
* [http://www.aps.org/publications/capitolhillquarterly/200802/physicshistory.cfm American Physical Society's Hubble Bio]
* [http://www.spacetelescope.org/about/history/the_man_behind_the_name.html Edwin Powell Hubble - The man who discovered the cosmos]
* [http://astroprofspage.com/archives/450 Astroprof's article on Hubble]
NAME=Hubble, Edwin Powell
SHORT DESCRIPTION=American astronomer
DATE OF BIRTH=birth date|1889|11|20|df=y
PLACE OF BIRTH=
DATE OF DEATH=death date|1953|9|28|df=y
PLACE OF DEATH=
San Marino, California
Wikimedia Foundation. 2010.