Quasars Essay -- Essays Papers

QuasarsSince their discovery, the nature of quasars has been one of the intimately intriguing and baffling problems as evidenced by the following quotations the problem of understanding quasi-stellar goals is one of the most key and fascinating tasks in all physics - G.Burbidge and Hoyle. The quasar continues to rank twain as one of the most baffling objects in the universe and one most capable of inspiring heated argument - Morrison. The redshift problem is one of the most critical problems in astronomy today - G. Burbidge. Quasars still remain the profoundest mystery in the heavens - Hazard and Mitton. The conventional interpretation of the spectral lines observed in quasars is based on the redshift theory. Three hypotheses have been advanced to account for the supposed redshifts 1. Cosmological hypothesis the redshifts are due to the expansion of the universe, 2. Gravitational hypothesis, 3 Local-Doppler hypothesis in this hypothesis the redshifts are due to the Dop pler effect, but the quasars are relatively nearby and have nothing to do with the expansion of the universe. Of these hypotheses, the first one is the most publicized one. One is led to attribute to quasars very many mysterious properties if one assumes the redshift hypothesis to be correct. A patient analysis of the data on quasars over the years has led to the conclusion that the real root of the trouble is in the assumption that the spectra of quasars have redshifts.In the early 1960s quasars were known as radio stars because the rule used to discover the first quasars was based on coincidences between a strong radio source and a point-like optical source. Since each radio source was associated with a star it was originally thought that quasars were objects within the galaxy hence the term radio stars. Quasars or quasi-stellar radio source, from the method by which they where originally discovered as stellar optical counterparts to small regions of strong radio emission. W ith increasing spatial resolution of radio telescopes the strong radio emission often seemed to come from a pair of lobes surrounding many of these faint star-like emission line objects.The initial method of selection was strong radio emission, and then later any object with blue or ultraviolet excess wa... ... between galaxies, either through direct collisions or near encounters, can be important in act on a quasar, by dumping fuel onto a black hole. However some quasars look unperturbed, so there may be other, to a greater extent subtle mechanisms for feeding the black hole. Some of the galaxies we observed dont appear to know they have a quasar in their core.3. Quasars that are radio quiet are often in elliptical galaxies, not always in spiral galaxies, as previously believed. Advanced instruments planned for Hubble should also help pin pig more details. The Near Infrared Camera and Multi-Object Spectrometer (NICMOS), to be installed in 1997, and the Advance d Camera, to be installed in 1999, will have coronagraphic devices which will block proscribed the glare of a quasar, allowing astronomers to see closer into a galaxys nucleus. By viewing galactic structures in infrared light , the NICMOS should be able to provide important new details about the host galaxies of quasars. The continued study of quasars and the information that it will provide us with may help us to develop a better understanding of space and how we fit in to this great puzzle.