Edwin Powell Hubble (November 20, 1889-September 28, 1953) was an American astronomer. He played a crucial role in establishing the fields of extragalactic astronomy and observational cosmology.
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 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 provided evidence that the recessional velocity of a galaxy increases with its distance from Earth, a property now known as Hubble's law, although it had been proposed two years earlier by Georges Lemaître.
The Hubble law implies that the universe is expanding. 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.
Hubble's name is most widely recognized for the Hubble Space Telescope, which was named in his honour, with a model prominently displayed in his hometown of Marshfield, Missouri.
More information: NASA
Edwin 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 studies at the University of Chicago were concentrated on mathematics, astronomy and philosophy, which resulted in a bachelor of science degree by 1910.
After the United States declared war on Germany in 1917, Hubble rushed to complete his Ph.D. dissertation so he could join the military. Hubble volunteered for the United States Army and was assigned to the newly created 86th Division, where he served in 2nd Battalion, 343 Infantry Regiment. He rose to the rank of Major, and was found fit for overseas duty on July 9, 1918, but the 86th Division never saw combat. After the end of World War I, Hubble spent a year at Cambridge University, where he renewed his studies of astronomy.
In 1919, Hubble was offered a staff position at the Carnegie Institution for Science's Mount Wilson Observatory, near Pasadena, California, by George Ellery Hale, the founder and director of the observatory. Hubble remained on staff at Mount Wilson until his death in 1953.
Shortly before his death, Hubble became the first astronomer to use the newly completed giant 5.1 m reflector Hale Telescope at the Palomar Observatory near San Diego, California.
Hubble also worked as a civilian for U.S. Army at Aberdeen Proving Ground in Maryland during World War II as the Chief of the External Ballistics Branch of the Ballistics Research Laboratory during which he directed a large volume of research in exterior ballistics which increased the effective firepower of bombs and projectiles.
Hubble had a heart attack in July 1949 while on vacation in Colorado. He was cared for by his wife and continued on a modified diet and work schedule. He died of in September 28, 1953, in San Marino, California. No funeral was held for him, and his wife never revealed his burial site.
Hubble's papers comprising the bulk of his correspondence, photographs, notebooks, observing logbooks, and other materials, are held by the Huntington Library in San Marino, California. They were donated by his wife Grace Burke Hubble upon her death in 1980.
At the time, the Nobel Prize in Physics did not recognize work done in astronomy. 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 Prize Committee 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. However, the prize is not one that can be awarded posthumously.
More information: Earth Sky
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