redshift
redshift (symbol
z) The amount by which the wavelength of light from a receding object is lengthened (i.e. moved to the red) by the
Doppler shift. Redshift is calculated from the formula
z = Δ λ / λ,where λ is the original wavelength (as measured in the laboratory) and Δ λ the observed change in wavelength. A redshift of 0.1, for example, means that the light has been redshifted by 10% in wavelength, whereas a redshift of 1 means a change of 100% (i.e. a doubling in wavelength). All galaxies at large distances from our own have redshifts resulting from the expansion of the Universe. At redshifts less than about 0.1,
z is related to the velocity of the object,
v, by the simple expression
z =
v/
c, where
c is the velocity of light. At larger redshifts, this relationship is no longer true, and it is better to think of the redshift as being caused by the expansion of space rather than a Doppler shift. While light is on its way to us from a distant object the Universe is expanding, and this expansion ‘stretches’ the wavelength of the light. For example, when the light left a galaxy with a redshift of 1 the Universe was only half its present size; during the time taken for the light to travel from the galaxy to our telescopes the Universe has doubled in size, causing the wavelength of the light to increase by the same factor.
A galaxy's redshift can be measured quite easily from its spectrum, unlike its distance, which is very hard to measure directly. At small redshifts, astronomers can calculate the velocity of the galaxy from its redshift and then use
Hubble's law, which relates velocity and distance, to estimate the distance of the galaxy. At larger redshifts, the expansion of the Universe means that distance becomes an ambiguous quantity, but astronomers can use a galaxy's redshift to estimate the age of the Universe at the time the light was emitted, which is the most important method they have for investigating the history of the Universe (see
galaxy evolution). The largest redshifts currently known are over 6, meaning that the light has been shifted in wavelength by 600% so that ultraviolet lines appear in the red part of the spectrum. See also
gravitational redshift;
Redshift Survey.
Cite this article
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 "Seattle Post-Intelligencer (Seattle, WA)")
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INTERNET OFFERS A FASCINATING PAGEANT OF HERALDRY INFORMATION.(Lifestyle)
Newspaper article from: Seattle Post-Intelligencer (Seattle, WA); 12/24/1998; 700+ words
; ...renewed interest in both genealogy and heraldry. According to the Mel Gibson movie...from The Baronage Press, which features heraldry and related subjects on its Web site...November 1998) includes pictures of the heraldry of Diana, Princess of Wales, and notes...
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Nothing escapes a heraldry expert's eagle eye
Newspaper article from: International Herald Tribune; 6/14/2006; ; 700+ words
; ...officials were from the Institute of Heraldry, the U.S. government's chief guardian...Joe Spollen, the chief sculptor at the heraldry institute, which among its other duties...learning the truth from the director of the heraldry office at the time, switched the gaze...
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 "The Hamilton Spectator (Hamilton, Ontario)")
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Heraldry not just a hobby; Order of Canada for Burlington man.(Local)
Newspaper article from: The Hamilton Spectator (Hamilton, Ontario); 7/14/2008; 700+ words
; ...been awarded the Order of Canada for his heraldry work. Left: bookplates for Rt. Rev...armorial bookplates. A founder of the Royal Heraldry Society of Canada in 1967, Macpherson...Canadian identities and achievements. Heraldry first captured his attention when he...
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INSTITUTE CREATES, PRESERVES U.S. MILITARY HERALDRY
News Wire article from: US Fed News Service, Including US State News; 7/24/2007; 700+ words
; ...Now, as director of the Institute of Heraldry, Mugno is one of the world's foremost...colorful divisions. The Institute of Heraldry is responsible for maintaining the nation...institute also creates and archives military heraldry and insignia. "We are our nation...
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 "Lancashire Evening Post (Preston, England)")
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Stories behind our heraldry.
Newspaper article from: Lancashire Evening Post (Preston, England); 4/14/2007; 389 words
; ...Family History is holding a study day on Heraldry and Local Family History today. The event...event is in association with the Lancashire Heraldry Group of the Lancashire Family History and Heraldry Society. As part of the study day, illustrated...
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The design of American heraldry: an interview with Charles V. Mugno.(Interview)
Magazine article from: Defense Transportation Journal; 4/1/2008; ; 700+ words
; The subject of heraldry conjures vibrant images of colorful...insignia, and political correctness. But heraldry also applies to NDTA member trademarks...Support Division at the Institute of Heraldry, sheds light on what lies behind the...
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Heraldry of Armenian Princes and Kings Dates Back to the
Newspaper article from: Armenian Reporter, The; 1/16/1999; 700+ words
; ...Armenian Reporter, The 01-16-1999 Heraldry of Armenian Princes and Kings Dates Back...existing evidence of the insignia and heraldry of several Armenia's major royal clans...to the Christian era in the field of heraldry. Prof. Chookaszian pointed to the imagery...
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Heraldry and the medieval gentlewoman: Maurice Keen looks at the significance of female lines of descent in heraldic arms, and what this tells us about women of noble and gentle birth in medieval England.
Magazine article from: History Today; 3/1/2003; ; 700+ words
; ...together a book of notes and comments on heraldry, a subject of keen interest to the gentility...social ideas and values reflected by heraldry in its early medieval days of vigorous...for daughters, by Strangways' time heraldry had found its means of recording women...
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Heraldry, Pageantry and Social Display in Medieval England.(Reviews of Books)(Book Review)
Magazine article from: Albion; 1/1/2004; ; 700+ words
; Peter Coss and Maurice Keen, eds. Heraldry, Pageantry and Social Display in Medieval...century. Many elements of this, such as heraldry, costume, tomb effigies and brasses...cast light on the family. Using the heraldry of two important kinship groups of the...
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Designs On the Military; Cameron Station's Heraldry Institute Creates Insignia
Newspaper article from: The Washington Post; 1/5/1989; ; 700+ words
; ...that go with it, then the Institute of Heraldry will knock your socks off, or at least...civilian employees of the Institute of Heraldry and nearly all the 330 Army personnel...sounding name? "The Institute of Heraldry is responsible for designing and for...
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heraldry
Book article from: The Columbia Encyclopedia, Sixth Edition
heraldry system in which inherited symbols, or...ancient (it is mentioned by Homer), but heraldry proper is a feudal institution developed...together knights from many countries caused heraldry to flourish in Western Europe and the...
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Heraldry
Encyclopedia entry from: Europe, 1450 to 1789: Encyclopedia of the Early Modern World
HERALDRY HERALDRY. "Heraldry" is a term that was coined in the late sixteenth century to designate the profession of the heralds of arms, a profession that originated in the twelfth century, reached the height of its prestige and influence...
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pale
Book article from: The Oxford Pocket Dictionary of Current English
...to which Jewish residence was restricted. 3. Heraldry a broad vertical stripe down the middle of a shield...language my father used was beyond the pale. in pale Heraldry arranged vertically. per pale Heraldry divided by a vertical line.
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argent
Book article from: The Oxford Pocket Dictionary of Current English
ar·gent / ˈärjənt / • adj. poetic/lit. & Heraldry silver; silvery white: the argent moon. • n. Heraldry silver as a heraldic tincture.
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genealogy
Book article from: The Oxford Companion to British History
...was closely argued. In the Middle Ages, genealogy was related to heraldry and of concern largely to the monarchy and nobility, to whom the...the past and rediscover one's ancestry grew stronger. See also heraldry . J. A. Cannon
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