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RD1 (radio Station)
RD1 or 0140+326 RD1 is a distant galaxy, it once held the title of most distant galaxy known. RD1 was discovered in March 1998, and is at ''z'' = 5.34,arXiv, , 11 March 1998 and was the first object found to exceed redshift 5.New York TimesPeering Back in Time, Astronomers Glimpse Galaxies Aborning, October 20, 1998 It bested the previous recordholders, a pair of galaxies at z=4.92 lensed by the galaxy cluster CL1358+62, CL 1358+62 (CL 1358+62 G1 & CL 1358+62 G2). It was the List of most distant astronomical object record holders, most distant object known to mankind for a few months in 1998, until BR1202-0725 LAE was discovered at ''z'' = 5.64. Distance measurements The "distance" of a far away galaxy depends on the chosen Distance measures (cosmology), distance measurement. With a redshift of 5.34, light from this galaxy is estimated to have taken around 12.5 Giga-, billion years to reach us. But since this galaxy is receding from Earth, the present comoving distance i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a Astronomical object, celestial body, as they are subject to Perturbation (astronomy), perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or Perihelion and aphelion, aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triangulum
Triangulum is a small constellation in the northern sky. Its name is Latin for "triangle", derived from its three brightest stars, which form a long and narrow triangle. Known to the ancient Babylonians and Greeks, Triangulum was one of the 48 constellations listed by the 2nd century astronomer Ptolemy. The celestial cartographers Johann Bayer and John Flamsteed catalogued the constellation's stars, giving six of them Bayer designations. The white stars Beta and Gamma Trianguli, of apparent magnitudes 3.00 and 4.00, respectively, form the base of the triangle and the yellow-white Alpha Trianguli, of magnitude 3.41, the apex. Iota Trianguli is a notable double star system, and there are three star systems with known planets located in Triangulum. The constellation contains several galaxies, the brightest and nearest of which is the Triangulum Galaxy or Messier 33—a member of the Local Group. The first quasar ever observed, 3C 48, also lies within the boundaries of Trian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giga-
Giga ( or ) is a unit prefix in the metric system denoting a factor of a short-scale billion or long-scale milliard (109 or ). It has the symbol G. ''Giga'' is derived from the Greek word (''gígas''), meaning "giant". The ''Oxford English Dictionary'' reports the earliest written use of ''giga'' in this sense to be in the Reports of the IUPAC 14th Conférence Internationale de Chimie in 1947: "The following prefixes to abbreviations for the names of units should be used: G giga 109×." When referring to information units in computing, such as gigabyte, giga may sometimes mean (230); this causes ambiguity. Standards organizations discourage this and use giga- to refer to 109 in this context too. ''Gigabit'' is only rarely used with the binary interpretation of the prefix. The binary prefix '' gibi'' has been adopted for 230, while reserving ''giga'' exclusively for the metric definition. Pronunciation In English, the prefix ''giga'' can be pronounced (a hard ''g'' as in ''gi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light-year
A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 (one million million, or billion in long scale). As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in a vacuum in one Julian year (365.25 days). Because it includes the time-measurement word "year", the term ''light-year'' is sometimes misinterpreted as a unit of time. The ''light-year'' is most often used when expressing distances to stars and other distances on a galactic scale, especially in non-specialist contexts and popular science publications. The unit most commonly used in professional astronomy is the parsec (symbol: pc, about 3.26 light-years) which derives from astrometry; it is the distance at which one astronomical unit subtends an angle of one second of arc. Defini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distance Measures (cosmology)
Distance measures are used in physical cosmology to give a natural notion of the distance between two objects or events in the universe. They are often used to tie some ''observable'' quantity (such as the luminosity of a distant quasar, the redshift of a distant galaxy, or the angular size of the acoustic peaks in the cosmic microwave background (CMB) power spectrum) to another quantity that is not ''directly'' observable, but is more convenient for calculations (such as the comoving coordinates of the quasar, galaxy, etc.). The distance measures discussed here all reduce to the common notion of Euclidean distance at low redshift. In accord with our present understanding of cosmology, these measures are calculated within the context of general relativity, where the Friedmann–Lemaître–Robertson–Walker solution is used to describe the universe. Overview There are a few different definitions of "distance" in cosmology which are all asymptotic one to another for small re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comoving Distance
In standard cosmology, comoving distance and proper distance are two closely related distance measures used by cosmologists to define distances between objects. ''Proper distance'' roughly corresponds to where a distant object would be at a specific moment of cosmological time, which can change over time due to the expansion of the universe. ''Comoving distance'' factors out the expansion of the universe, giving a distance that does not change in time due to the expansion of space (though this may change due to other, local factors, such as the motion of a galaxy within a cluster). Comoving distance and proper distance are defined to be equal at the present time. At other times, the Universe's expansion results in the proper distance changing, while the comoving distance remains constant. Comoving coordinates Although general relativity allows one to formulate the laws of physics using arbitrary coordinates, some coordinate choices are more natural or easier to work with. Com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redshift
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in frequency and energy, is known as a negative redshift, or blueshift. The terms derive from the colours red and blue which form the extremes of the visible light spectrum. In astronomy and cosmology, the three main causes of electromagnetic redshift are # The radiation travels between objects which are moving apart (" relativistic" redshift, an example of the relativistic Doppler effect) #The radiation travels towards an object in a weaker gravitational potential, i.e. towards an object in less strongly curved (flatter) spacetime (gravitational redshift) #The radiation travels through expanding space (cosmological redshift). The observation that all sufficiently distant light sources show redshift corresponding to their distance from Earth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CL1358+62
CL 1358+62 (ClG 1358+62) is a galaxy cluster located at z=0.33 redshift. Behind the cluster (which itself lies at a distance of about 3.9 billion light years), lensed into a red arc is an infant galaxy (CL 1358+62 G1) that was the farthest object in the observable universe for a few months. It had a record redshift of z=4.92 and was discovered on July 31, 1997 by M. Franx and G. Illingsworth. It is located approximately 26 billion light years from Earth. Its redshift was measured by the Keck Telescope shortly after its discovery. Along with G1, another galaxy also lensed, was found to be at z=4.92 ( CL 1348+62 G2). The pair of galaxies were the first things other than quasars to have the title of most distant object found, since the 1960s. The pair of galaxies remained the most distant objects known until the discovery of RD1 at z=5.34,arXiv, , 11 March 1998 the first object to exceed redshift In physics, a redshift is an increase in the wavelength, and corresponding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CL 1358+62 G1
CL or cl may refer to: Arts and entertainment * CL (rapper) or Lee Chae-rin (born 1991), singer and rapper, former leader of the K-pop girl group 2NE1 * Creative Loafing, a newspaper publisher Brands and enterprises * Colgate-Palmolive's NYSE stock symbol * Companhia das Lezírias, an agribusiness company in Portugal Computing and technology * , the command-line C/C++ compiler for Microsoft Visual C++ * .cl, Internet country code top-level domain for Chile * CL register, the low byte of an X86 16-bit CX register * CAS latency, a measure used in computer memory * Common Lisp, a programming language * Common Logic, a framework for a family of logic languages * Control Language, a scripting language for the IBM AS/400 midrange platform Industry and technology * CL, the prefix for Canadair manufactured aircraft model numbers * Caseless ammunition Organizations * Catholic League (U.S.), also known as The Catholic League for Religious and Civil Rights * Communion and Libe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CL 1358+62 G2
CL or cl may refer to: Arts and entertainment * CL (rapper) or Lee Chae-rin (born 1991), singer and rapper, former leader of the K-pop girl group 2NE1 * Creative Loafing, a newspaper publisher Brands and enterprises * Colgate-Palmolive's NYSE stock symbol * Companhia das Lezírias, an agribusiness company in Portugal Computing and technology * , the command-line C/C++ compiler for Microsoft Visual C++ * .cl, Internet country code top-level domain for Chile * CL register, the low byte of an X86 16-bit CX register * CAS latency, a measure used in computer memory * Common Lisp, a programming language * Common Logic, a framework for a family of logic languages * Control Language, a scripting language for the IBM AS/400 midrange platform Industry and technology * CL, the prefix for Canadair manufactured aircraft model numbers * Caseless ammunition Organizations * Catholic League (U.S.), also known as The Catholic League for Religious and Civil Rights * Communion and Libe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Most Distant Astronomical Object Record Holders
This article documents the most distant astronomical objects discovered and verified so far, and the time periods in which they were so classified. For comparisons with the light travel distance of the astronomical objects listed below, the age of the universe since the Big Bang is currently estimated as 13.787±0.020 Gyr. Distances to remote objects, other than those in nearby galaxies, are nearly always inferred by measuring the cosmological redshift of their light. By their nature, very distant objects tend to be very faint, and these distance determinations are difficult and subject to errors. An important distinction is whether the distance is determined via spectroscopy or using a photometric redshift technique. The former is generally both more precise and also more reliable, in the sense that photometric redshifts are more prone to being wrong due to confusion with lower redshift sources that may have unusual spectra. For that reason, a spectroscopic redshift is conventio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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