Breaking the redshift-4 barrier.Breaking the redshift-4 barrier For cosmologists, a redshift redshift Displacement of the spectrum of an astronomical object toward longer wavelengths (visible light shifts toward the red end of the spectrum). In 1929 Edwin Hubble reported that distant galaxies had redshifts proportionate to their distances (see value of 4 used to seem like the 4-minute mile in footracing. For a long time, in spite of diligent searching, no object with a redshift greater than 4 could be found. Cosmologists wondered whether the horizon of the universe might be somewhere around the distance represented by redshift 4, and so we would never be able to see beyond it. However, it has turned out not to be the horizon, and we do see beyond it. As with the 4-minute mile, once the barrier was broken, new records were posted swiftly. There are now at least three known quasars Proper naming of quasars are by Catalogue Entry, Qxxxx±yy using B1950 coordinates, or QSO Jxxxx±yyyy using J2000 coordinates. This page lists quasars.
In nature, the most common cause of redshift--a systematic reddening of an object's light--is motion away from the observer. According to the expanding-universe theory, the greater an object's recession velocity, the farther away it is. The redshift of 4.11 translates to a velocity of 93 percent of the speed of light, according to an announcement by the European Southern Observatory European Southern Observatory (ESO), an intergovernmental organization for astronomical research with headquarters in Garching, near Munich, Germany. The ESO began in 1962 as a consortium among Belgium, Denmark, France, Germany, the Netherlands, and Sweden. (ESO ESO European Southern Observatory ESO Educación Secundaria Obligatoria (Spain: compulsory secondary education) ESO European Organisation for Astronomical Research in the Southern Hemisphere ESO Edmonton Symphony Orchestra ) in Cerro La Silla, Chile. The first object with a redshift greater than 4 was the quasar quasar (kwā`sär), one of a class of blue celestial objects having the appearance of stars when viewed through a telescope and currently believed to be the most distant and most luminous objects in the universe; the name is shortened from 0046-293, with a redshift of 4.01 reported in the Jan. 8, 1987 NATURE by S.J. Warren, and colleagues. from the Institute of Astronomy in Cambridge, England. In the Oct. 1 ASTROPHYSICAL JOURNAL LETTERS Maarten Schmidt of California Institute of Technology California Institute of Technology, at Pasadena, Calif.; originally for men, became coeducational in 1970; founded 1891 as Throop Polytechnic Institute; called Throop College of Technology, 1913–20. in Pasadena, Donald P. Schneider of the Institute for Advanced Study in Princeton, N.J., and James E. Gunn
The third, Q0000-26, found by Cyril Hazard of the University of Pittsburgh and Richard McMahon and Mike Irwin of the Institute of Astronomy, has the record-breaking redshift of 4.11. That means we are seeing Q0000-26 as it was when the universe was only a tenth of its present age, or approximately 18 billion years ago if we accept the most widely used value for the age of the universe. John Webb of ESO has obtained detailed spectra of Q0000-26. Early results from the analysis of these spectra "are causing great excitement among astrophysicists,' says the ESO announcement. These spectra "will permit the investigation of matter in the universe at an earlier time than ever before possible,' says ESO. |
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