The birth of twin quasars.The birth of twin quasars Astronomers have resolved a distant, fuzzy patch of light designated PHL 1222 into two separate objects that may represent a pair of quassars less than 100,000 light-years apart. 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.
v. out·shone , out·shin·ing, out·shines v.tr. 1. a. To shine brighter than. b. To be more beautiful, splendid, or flamboyant than. 2. the "host" galaxies enveloping en·vel·op tr.v. en·vel·oped, en·vel·op·ing, en·vel·ops 1. To enclose or encase completely with or as if with a covering: "Accompanying the darkness, a stillness envelops the city" them. The discovery of two so close togeterh indicates the host galaxies may have a strong gravitational grav·i·ta·tion n. 1. Physics a. The natural phenomenon of attraction between physical objects with mass or energy. b. The act or process of moving under the influence of this attraction. 2. influence on each other. That could have been responsible for turning on both quasars, says George Meylan of the Space Telescope Science Institute The Space Telescope Science Institute (STScI) is the science operations center for the Hubble Space Telescope (HST; in orbit since 1990) and for the James Webb Space Telescope (JWST; scheduled to be launched in 2013). in Baltimore, who led the team making the discovery. Astronomers have detected apparent quasar pairs in the past, by those images instead represented light from a single, distant quasar split into two components by the gravitational effects of an intervening galaxy between the quasar and the Earth-based observers. In such gravitationally grav·i·ta·tion n. 1. Physics a. The natural phenomenon of attraction between physical objects with mass or energy. b. The act or process of moving under the influence of this attraction. 2. lensed quasars, both components have identical spectra, confirming that the light comes from the same source. In contrast, the two quasars that make up PHL 1222 have slightly different spectra. The newly identified quasars also appear to be approaching each other with velocities typical of galaxies in a cluster, and they have a spectral 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 of 1.91, indicating that the light seen was emitted as much as 12 billion years ago. These observations suggest that rich clusters of galaxies may have existed early in the history of the universe, putting a significant constraint on theories attempting to explain the formation of large-scale structure in the early universe. The discovery of the twin quasars in PHL 1222 also provides evidence that close encounters between galaxies may be responsible for turning on many quasars. Computer simulations show that encounters between galaxies can cause gravitational effects capable of driving huge amounts of gas into the inner regions of the galaxies. Such a mass concentration could develop into a black hole, and matter swirling into the hole would generate prodigious amounts of radiation. Galactic near-collisions would have been much more common 12 billion years ago, when the universe was smaller and galaxies closer together, the researchers say. That would help explain why the majority of quasars emerged billions of years ago and are now seen at such great distances. |
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