Brightness is an attribute of visual perception in which a source appears to be radiating or reflecting light . ref http www.merriam webster.com dictionary bright Merriam Webster.com Merriam Webster Dictionary definition of bright ref In other words, brightness is the perception elicited by the luminance of a visual target. This is a subjective attribute property of an object being observed. Terminology wiktionary brightness The adjective wikt bright bright derives from an Old English beorht with the same meaning via metathesis giving Middle English briht . The word is from a Common Germanic lang gem berhtaz , ultimately from a Proto Indo European language PIE root with a closely related meaning, PIE bhereg white, bright . Brightness was formerly used as a synonym for the photometry optics photometric term luminance and incorrectly for the radiometric term radiance . As defined by the US Federal Glossary of Telecommunication Terms Federal Standard 1037C FS 1037C , brightness should now be used only for non quantitative references to physiological sensations and perceptions of light. ref http www.its.bldrdoc.gov fs 1037 dir 005 0719.htm Brightness in Federal Standard 1037C, the Federal ... of brightness in different contexts see, for example, White s illusion and Wertheimer Benary illusion. In the RGB color space , brightness can be thought of as the arithmetic mean &mu of the red ... formulation of HSB and HLS compute so called lightness or brightness as R G B 3. This computation ... more intense than blue with the same lightness value say L 50 . ref math mu R G B over 3 math Brightness ... , and brightness or value . With regard to star s, brightness is quantified as apparent magnitude and absolute magnitude . Brightness of sounds The term brightness is also used in discussions of sound timbre s, in a rough analogy with visual brightness. Timbre researchers consider brightness to be one ... relative Luminosity Notes reflist External links Wiktionarypar brightness http www.poynton.com ... more details
for the attribute of visual perception brightness Infobox Album See Wikipedia WikiProject Albums Name The Brightness Type Album Artist Ana s Mitchell Cover RBR053 thebrightness.jpg Released February 13, 2007 Recorded Genre folk music Folk Length 39 34 Label Righteous Babe Records Producer Michael Chorney Reviews Allmusic Rating 3.5 5 ref name amg Allmusic class album id r947395 pure url yes Review Ana s Mitchell The Brightness by Margaret Reges, Allmusic ref Folkwax 7 10 ref http www.visnat.com entertainment music folkwax mp3 album.cfm?aaa zzz&reviewnumber 2153 Brightly Experimental small requires free membership small by Arthur Wood, Folkwax , February 28, 2007 ref PopMatters 6 10 ref name pm http www.popmatters.com pm music reviews 32953 anais mitchell the brightness Review Ana s Mitchell The Brightness by Aarik Danielsen, PopMatters ref Last album Hymns for the Exiled br 2004 This album The Brightness br 2007 Next album Country E.P. br 2008 The Brightness is the third album by American folksinger Anais Mitchell , released February 13, 2007 on Righteous Babe Records . It was recorded at The Bristmill in Bristol, Vermont and produced by Michael Chorney . Track listing Your Fonder Heart Of A Friday Night Namesake Shenandoah Changer Song of the Magi Santa Fe Dream Hobo s Lullaby Old Fashioned Hat Hades & Persephone Out of Pawn References reflist DEFAULTSORT Brightness Category Ana s Mitchell albums Category 2007 albums 2000s folk album stub ... more details
Orphan date February 2009 sources date December 2007 astronomy Astronomers use the term intrinsic brightness also termed absolute magnitude to refer to how bright a star would be without the effects of distance or absorption due to interstellar dust or gas. While a bright distant star s apparent brightness might be less than a nearby dim star, due to the inverse square law for brightness, astronomers can discuss its intrinsic brightness meaning how bright the stars would be at a common distance. category Observational astronomy de Absolute Helligkeit ... more details
Unreferenced date October 2008 Brightness temperature is the temperature a black body in thermal equilibrium with its surroundings would have to be to duplicate the observed Intensity heat transfer intensity of a grey body object at a frequency math nu math . This concept is extensively used in radio astronomy and planetary science . For a black body , Planck s law gives math I nu frac 2 h nu 3 c 2 frac 1 e frac h nu kT 1 math where math I nu d nu math aka. Brightness is the amount of energy per unit surface per unit time per unit solid angle emitted in the frequency range between math nu math and math nu d nu math math T math is the temperature of the black body math h math is Planck s constant math nu math is frequency . math c math is the speed of light and math k math is Boltzmann s constant . For a grey body the spectral radiance is a portion of the black body radiance, determined by the emissivity math epsilon math . That makes the reciprocal of the brightness temperature math T b 1 frac k h nu , text ln left 1 frac e frac h nu kT 1 epsilon right math At low frequency and high temperatures, when math h nu ll kT math , we can use the Rayleigh Jeans law math I nu frac 2 nu 2k T c 2 math so that the brightness temperature can be simply written as math T b epsilon T , math Removed text that claims that brighness temperatures are only useful in Rayleigh Jeans regime. That is not as all true Brightness temperature is a useful diagnostic for temperature measurement if the astronomical source is a black body and we are in the Rayleigh Jeans regime. It is not useful if the source ... into the expression for brightness temperature we find math T b frac h nu k text Exp h nu k T 1 math So, e.g. for the Sun, where the temperature may be estimated to be 6000K, we can plot the brightness ..., the brightness temperature and physical temperature are the same, but at higher temperatures the brightness temperature is much lower. Image with unknown copyright status removed Image brightness temp2.jpg ... more details
The overall brightness of an extended astronomical object such as a galaxy , star cluster , or nebula , can be measured by its total magnitude , integrated magnitude or integrated visual magnitude a related concept is surface brightness , which specifies the brightness of a standard sized piece of an extended object. General description The total magnitude is a measure of the brightness of an extended object such as a nebula, cluster or galaxy. It can be obtained by summing up the luminosity over the area of the object. Alternatively, a photometer can be used by applying apertures or slits of different sizes diameter. ref name daintith gould2005 cite book author Daintith, John Gould, William year 2006 title The Facts on File dictionary of astronomy page 489 series Facts on File science library edition 5th publisher Infobase Publishing isbn 0816059985 ref The background light is then subtracted from the measurement to obtain the total brightness. ref name sa12 164 cite journal last Palei first A. B. title Integrating Photometers journal Soviet Astronomy volume 12 page 164 month August ... against the airglow background light. Quoting an object s surface brightness gives an indication of how easily observable it is. Calculating surface brightness Surface brightnesses are usually ... brightness cannot be done by simple division of magnitude by area. Instead, for a source with magnitude m extending over an area of A square arcseconds, the surface brightness S is given by math S m 2.5 cdot log 10 A. math Surface brightness is constant with luminosity distance . For nearby objects ... fashion, resulting in the same surface brightness. ref harvtxt Sparke Gallagher 2000 loc § 5.1.2 ref Relationship to physical units The surface brightness in magnitude units is related to the surface brightness in physical units of solar luminosities per square parsec by math S mag arcsec .... See also Low surface brightness galaxy References reflist General references Cite book last Binney ... more details
About the Jay McInerney novel the Hampdens EP The Hampdens the David Sylvian and Robert Fripp song The First Day David Sylvian and Robert Fripp album orphan date September 2010 Unreferenced stub auto yes date December 2009 File BrightnessFalls.jpg thumb right 1st edition publ. Alfred A. Knopf Knopf Brightness Falls is a 1992 novel written by Jay McInerney . His fourth novel, it tells of a couple named Russell and Corrine Calloway who meet in college. Their story continues in McInerney s 2006 novel The Good Life novel The Good Life , which follows them into middle age. DEFAULTSORT Brightness Falls Category 1992 novels Category American novels Category Novels by Jay McInerney Category Alfred A. Knopf books 1990s novel stub ... more details
Cleanup date January 2009 Unreferenced date January 2009 This article is primarily about the brightness of the night sky night sky . For daytime situations, please see diffuse sky radiation and Rayleigh scattering . Image Orion1 big.jpg thumb 300px right Airglow made visible from aboard the ISS NASA The fact that the sky is not completely dark at night can be easily observed. Were the sky in the absence of moon and city lights absolutely dark, one would not be able to see the silhouette of an object against the sky. The intensity of the sky varies greatly over the day and the primary cause differs as well. During daytime when the sun is above the horizon direct scattering of sunlight Rayleigh scattering is the overwhelmingly dominant source of light. In twilight, the period of time between sunset and sunrise, the situation is more complicated and a further differentiation is required. Twilight ... 18 below the horizon the sky generally attains its minimum brightness. Several sources can be identified as the source of the intrinsic brightness of the sky, namely airglow , indirect scattering of sunlight ... of sky brightness in urbanized areas. In densely populated areas that don t have stringent light pollution ... including moonshine . This article is about natural sky brightness, for more information about light pollution please visit the light pollution article. Twilight When the sun has just set the brightness ... table gives the relative and absolute contributions to night sky brightness at zenith on a perfectly ... wikitable style text align center border collapse collapse cellpadding 2 Night sky brightness style background efefef Cause style background efefef Surface brightness S sub 10 sub style background efefef ... is defined as the surface brightness of a star whose V magnitude is 10 and whose light is smeared over one square degree, or 27.78 mag arcsec sup 2 sup . The total sky brightness in zenith is therefore ... sky brightness can be as high as 21.0 mag arcsec , roughly twice as bright as nominal conditions ... more details
Infobox Book See Wikipedia WikiProject Novels or Wikipedia WikiProject Books name Brightness Reef title orig translator image Image Brightness Reef Cover.jpg 200px image caption Cover of first edition hardcover author David Brin illustrator cover artist country United States language English language English series Uplift Universe genre Science fiction novel publisher Bantam Books release date October 1995 english release date media type Print Hardcover & Paperback pages 518 pp isbn 0 553 10034 3 dewey 813 .54 20 congress PS3552.R4825 B75 1995 oclc 32429193 preceded by The Uplift War followed by Infinity s Shore Brightness Reef is a 1995 science fiction novel by David Brin and the fourth book of six set in his Uplift Universe preceded by The Uplift War and followed by Infinity s Shore . It was nominated for both the Hugo Award Hugo and Locus Award Locus Awards in 1996. ref name WWE 1996 cite web url http www.worldswithoutend.com books year index.asp?year 1996 title 1996 Award Winners & Nominees work Worlds Without End accessdate 2009 07 17 ref Synopsis Starting around the year 930 Common Era C.E. , and continuing until the 23rd century, sooner s belonging to eight patron class races illegally plant colonies on the planet List of Uplift Universe planets Jijo . Sooner is a term from US history, and is used in the Uplift stories to described illegal settlers on worlds that have been declared fallow, i.e. to be left uncolonized so that the ecosystem will recover and native intelligences may have a chance to develop. The eight races are List of Uplift Universe species g Keks , List ... www.worldswithoutend.com novel.asp?ID 85 Brightness Reef at Worlds Without End Translations French ... of the Dolphins , 2001. Polish language Polish Rafa jasno ci The Reef of Brightness , 1997. Russian language Russian lang ru The Reef of Brightness , 2003. Russian language Serbian lang sr Brightness Reef , 1997. Spanish language Spanish Arrecife Brillante Bright ... more details
Infobox Book name In the Claws of Brightness image File Sa mga Kuko ng Liwanag ni Edgardo Reyes Tagalog Bookcover.jpg 220px image caption Book cover for Edgardo M. Reyes s Sa mga Kuko ng Liwanag . author Edgardo M. Reyes country Philippines language Tagalog language Tagalog genre Fiction media type publisher De La Salle University Press release date pages isbn File Sa mga Kuko ng Liwanag ni Edgardo Reyes Japanese Bookcover.jpg thumb right 180px The Nihonggo Japanese book cover for Edgardo M. Reyes s Sa mga Kuko ng Liwanag . In the Claws of Brightness Filipino language Filipino Sa mga Kuko ng Liwanag , is a 1986 Tagalog language novel written by Filipino author Edgardo M. Reyes . The book was the basis of the FAMAS award winning Philippines Philippine Cinema in the Philippines film , The Claws of Light . ref name GR Summary Julio, a poor fisherman, went to Manila to search for his childhood friend and girlfriend named Ligaya. Sometime before Julio s trip, Ligaya went with a lady named Mrs. Cruz in order to study and work in the city. During the search, Julio became a victim of some city dwellers. Julio experienced abuses while working at construction sites, he lost his job, he had to sleep in any place he could find, and he unintentionally killed somebody. In the midst of the pressure of city life and his failures, Julio was transformed from a gentle person into a fierce and dangerous man. Julio eventually met Ligaya and found out that she was a victim of White slavery prostitution white slavery . Ligaya was bought and lived like a prisoner under the authority of a Chinese businessman. Despite the obstacles, Julio and Ligaya decided to free themselves. ref name Kabayan http www.kabayancentral.com book others mb5846173.html Sa Mga Kuko ng Liwanag by Edgardo M. Reyes Tagalog , kabayancentral.com ref Film adaptation The 1975 in film 1975 adaptation entitled The Claws of Light that was based on Edgardo M. Reyes s novel was directed by award winning director Lino Brocka . The script ... more details
orphan date January 2011 unreferenced date January 2011 A high brightness monitor , also known as a sunlight readable monitor or VHB very high brightness monitor is a computer monitor designed to operate in very bright environments, for example in broad daylight . High brightness monitors are typically used commercially in kiosk s and out of home advertising . Category Computer peripherals Category Display devices Comp hardware stub ... more details
The Tolman surface brightness test is one out of a half dozen cosmological test s that was conceived in the 1930s to check the viability of and compare new cosmological model s. Tolman s test compares the surface brightness of galaxy galaxies as a function of their redshift measured as z . Such a comparison was first proposed in 1930 by Richard C. Tolman as a test of whether the universe is expanding universe expanding or static universe static . Different physicists have claimed that the results support different models. Who date March 2009 In a simple static and flat universe, the light received from an object drops inversely with the square of its distance, but the apparent area of the object also drops inversely with the square of the distance, so the surface brightness would be independent of the distance. In an expanding universe, however, there are two effects that reduce the power detected coming from distant objects. First, the rate at which photons are received is reduced because each photon has to travel a little farther than the one before. Second, the energy of each photon ... together, the surface brightness in a simple expanding universe flat geometry and uniform expansion ..., the best investigation of the relationship between surface brightness and redshift was carried out ... and the 94 inch HST to measure those galaxies surface brightness. ref Allan Sandage and Lori M. Lubin, 2271 88 Lori M. Lubin and Allan Sandage, The Tolman Surface Brightness Test for the Reality ... Surface Brightness Test for the Reality of the Expansion. III. Hubble Space Telescope Profile and Surface Brightness Data for Early Type Galaxies in Three High Redshift Clusters, Astronomical Journal 122 2001 1071 83 Lori M. Lubin and Allan Sandage, The Tolman Surface Brightness Test for the Reality .... We conclude that the Tolman surface brightness test is consistent with the reality of the expansion ... sv Tolman Surface Brightness Test ... more details
Summary book cover fur Article Brightness Reef Use Infobox OPTIONAL FIELDS Title Brightness Reef Author David Brin Publisher Bantam Books Cover artist country United States Website http pictures.abebooks.com ADVUNDERGROUND 417447616.jpg Owner Commentary Year 1995 OVERRIDE FIELDS Description Source Portion Low resolution Purpose Replaceability Other information Low res scan of book cover Brightness Reef by David Brin, 1995 Bantam Books first edition hardcover for use in illustrating article about book. Retrieved from http pictures.abebooks.com ADVUNDERGROUND 417447616.jpg and subsequently cropped. Licensing Non free book cover ... more details
A low surface brightness galaxy , or LSB galaxy , is a diffuse galaxy with a surface brightness that, when viewed from Earth , is at least one magnitude lower than the ambient night sky. Most LSBs are dwarf galaxy dwarf galaxies , and most of their baryon ic matter is in the form of neutral gaseous hydrogen, rather than stars. They appear to have over 95 Citation needed date July 2007 of their mass as non baryon ic dark matter . There appears to be no supernova activity in these galaxies. Rotation curve measurements indicate an extremely high mass to light ratio, meaning that stars and luminous gas contribute only very little to the overall mass balance of an LSB. The centers of LSBs show no large overdensities in stars, unlike e.g. the bulge astronomy bulge s of normal spiral galaxies. Therefore they seem to be dark matter dominated even in their centers which makes them excellent laboratories for the study of dark matter. In comparison to the more well studied high surface brightness galaxies, LSBs are mainly isolated field galaxies , found in regions devoid of other galaxies. In their past, they had fewer tidal interactions or mergers with other galaxies, which could have triggered enhanced star formation. This is an explanation for the small stellar content. Examples col begin col 3 Andromeda V hiding redlinks and non link comments i.e. if this Examples of section is to take the format of a See also one, which it probably should, unless converted to paragraphical form with more explanations added per item Andromeda VI or Pegasus Dwarf Spheroidal Galaxy Peg dSph Antlia Dwarf Galaxy f561 1 f611 1 IC 10 col 3 Malin 1 Malin 2 Phoenix Dwarf Galaxy Sagittarius Dwarf Irregular ... Surface Brightness Galaxies Could LSB Galaxies be Responsible for Damped Ly alpha Absorption? . For publication ... Brightness Galaxies . Astronomy & Astrophysics Letters , 422, 5 8 2004 . A.J. Barth, http lanl.arxiv.org ... 1091 2007 . Category Low surface brightness galaxies galaxy stub es Galaxia de bajo brillo superficial ... more details
Surface brightness fluctuation SBF is a secondary standard candle distance indicator used to estimate distances to galaxies. The technique uses the fact that galaxies are made up of a finite number of stars. The number of stars in any small patch of the galaxy will vary from point to point, creating a noise like fluctuation in the surface brightness distribution. While the various stars present in a galaxy will cover an enormous range in luminosity, the SBF can be characterized as if all stars had the same brightness, which is the luminosity weighted integral over the luminosity distribution of stars. Older elliptical galaxies have fairly consistent stellar populations, thus the typical fluctuation star closely approximates a standard candle . In practice, corrections are required to account for variations in age or metallicity from galaxy to galaxy. The SBF pattern is measured from the power spectrum of the residuals left behind from a deep galaxy image after a smooth model of the galaxy has been subtracted. The SBF pattern is evident as the transform of the point spread function in the Fourier domain . The amplitude of the spectrum gives the luminosity of the fluctuation star. Because the technique depends on a precise understanding of the image structure of the galaxy, extraneous sources such as globular cluster s and background galaxies must be excluded from the analysis. Areas of interstellar dust absorption must also be excluded. In practice this means that SBF works best for elliptical galaxies or the bulges of S0 galaxy S0 galaxies , as spiral galaxies generally have complex morphologies and extensive dust features. SBF is calibrated by use of fiducial Cepheid Period Luminosity relation P L based on observations of Cepheid variable variables located in the Large Magellanic Cloud . Harv Tonry 2001 Harv Macri 2006 SBF is an indicator that uses stars in the old stellar ... Function, and Surface Brightness Fluctuation Data Useful for Distance Determinations journal ... more details
Summary This is a copy of the smallest star on Image Featured stars.png 200px with some modifications of hue and brightness. Licensing GFDL migration relicense ... more details
Summary Delicious bu uelitos Photo by Fisherjs, edited by Sagredo contrast and brightness adjustment Licensing PD self date October 2006 ... more details
Summary Original image was in public domain. Adjusted brightness and contrast to improve detail. Licensing PD release Category Lakehead University ... more details
Unreferenced date July 2009 orphan date December 2007 Ziff is an unknown metal mentioned in the Book of Mormon Book of Mosiah Mosiah 11 3,8 . In Hebrew language Hebrew , this term means brightness, i.e. metallic brightness. material stub LDS stub Category Metals Category Book of Mormon words and phrases ... more details
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